hypothesis on why the sky is blue

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Why Is the Sky Blue?

One of the perennial questions of childhood is “Why is the sky blue?” You may have asked this as a child, or you may have a child now asking you! The explanation begins with the ultimate source of light in our solar system: the Sun . Sunlight appears white, but this white light is made up of all the colors of the visible spectrum, ranging from red through violet. On its path through the atmosphere , sunlight is absorbed, reflected, and altered by different elements, compounds, and particles. The color of the sky depends largely upon the wavelengths of the incoming light, but air molecules (mostly nitrogen and oxygen ) and dust particles also play important roles.

When the sun is high overhead, the bulk of its rays intercept the atmosphere at nearly vertical angles. Shorter wavelengths of light, such as violet and blue, are more easily absorbed by air molecules than light from longer wavelengths (that is, from red, orange, and yellow bands in the spectrum). Air molecules then radiate violet and blue light in different directions, saturating the sky. However, the midday sky appears blue, rather than a combination of blue and violet, because our eyes are more sensitive to blue light than to violet light.

When the sun is near the horizon at dawn and dusk, the sun’s rays strike the atmosphere at more-oblique (slanted) angles, and thus these rays must travel a greater distance through the atmosphere than they would at midday. As a result, there are more nitrogen and oxygen molecules and other particles that can block and scatter incoming sunlight. During this long passage, incoming radiation in the shorter blue and violet wavelengths is mostly filtered out, and the influence of these wavelengths over the color of the sky diminishes. What remains are the longer wavelengths, and some of these rays strike dust and other particles near the horizon, as well as the water droplets that make up clouds , to create the red, orange, and yellow tints we enjoy at sunrise and sunset.

April 7, 2003

Why is the sky blue?

Anthony D. Del Genio of the NASA Goddard Institute for Space Studies and Columbia University explains.

To understand why the sky is blue, we need to consider the nature of sunlight and how it interacts with the gas molecules that make up our atmosphere. Sunlight, which appears white to the human eye, is a mixture of all the colors of the rainbow. For many purposes, sunlight can be thought of as an electromagnetic wave that causes the charged particles (electrons and protons) inside air molecules to oscillate up and down as the sunlight passes through the atmosphere. When this happens, the oscillating charges produce electromagnetic radiation at the same frequency as the incoming sunlight, but spread over all different directions. This redirecting of incoming sunlight by air molecules is called scattering.

The blue component of the spectrum of visible light has shorter wavelengths and higher frequencies than the red component. Thus, as sunlight of all colors passes through air, the blue part causes charged particles to oscillate faster than does the red part. The faster the oscillation, the more scattered light is produced, so blue is scattered more strongly than red. For particles such as air molecules that are much smaller than the wavelengths of visible light the difference is dramatic. The acceleration of the charged particles is proportional to the square of the frequency, and the intensity of scattered light is proportional to the square of this acceleration. Scattered light intensity is therefore proportional to the fourth power of frequency. The result is that blue light is scattered into other directions almost 10 times as efficiently as red light.

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When we look at an arbitrary point in the sky, away from the sun, we see only the light that was redirected by the atmosphere into our line of sight. Because that occurs much more often for blue light than for red, the sky appears blue. Violet light is actually scattered even a bit more strongly than blue. More of the sunlight entering the atmosphere is blue than violet, however, and our eyes are somewhat more sensitive to blue light than to violet light, so the sky appears blue.

When we view the setting sun on the horizon, the opposite occurs. We see only the light that has not been scattered into other directions. The red wavelengths of sunlight that pass through the atmosphere without being scattered much reach our eyes, while the strongly scattered blue light does not. The longer distance that the sunlight travels through the atmosphere when it is on the horizon amplifies the effect--there are more opportunities for blue light to be scattered than when the sun is overhead. Thus, the setting sun appears reddish. In a polluted sky, small aerosol particles of sulfate, organic carbon, or mineral dust further amplify the scattering of blue light, making sunsets in polluted conditions sometimes spectacular.

Clouds, on the other hand, are made of water droplets that are much larger than the wavelengths of visible light. The way they scatter sunlight is determined by how the light is refracted and internally reflected by, and diffracted around, the cloud droplets. For these particles the difference between the scattering of blue and red light is not nearly so large as it is for gas molecules. Hence, our eyes receive substantial scattered light at all visible wavelengths, causing clouds to appear more white than blue, especially when viewed against a blue sky background.

Since scattering by the atmosphere causes the sky to be blue, a planet with no atmosphere cannot have a bright sky. For example, photographs taken by the Apollo astronauts on the moon show them and the moon's surface bathed in sunlight, but a completely dark sky in all directions away from the sun.

Why Is the Sky Blue?

Click above to watch this video about why the sky is blue! Voiceover provided by NASA scientist Dr. Moogega Stricker. Click here to download this video (1920x1080, 87 MB, video/mp4).

It's easy to see that the sky is blue. Have you ever wondered why?

A lot of other smart people have, too. And it took a long time to figure it out!

The light from the Sun looks white. But it is really made up of all the colors of the rainbow.

When white light shines through a prism, the light is separated into all its colors. A prism is a specially shaped crystal.

If you visited The Land of the Magic Windows , you learned that the light you see is just one tiny bit of all the kinds of light energy beaming around the universe--and around you!

Like energy passing through the ocean, light energy travels in waves, too. Some light travels in short, "choppy" waves. Other light travels in long, lazy waves. Blue light waves are shorter than red light waves.

All light travels in a straight line unless something gets in the way and does one of these things:—

reflect it (like a mirror)

bend it (like a prism)

or scatter it (like molecules of the gases in the atmosphere)

Sunlight reaches Earth's atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.

Closer to the horizon, the sky fades to a lighter blue or white. The sunlight reaching us from low in the sky has passed through even more air than the sunlight reaching us from overhead. As the sunlight has passed through all this air, the air molecules have scattered and re scattered the blue light many times in many directions .

Also, the surface of Earth has reflected and scattered the light. All this scattering mixes the colors together again so we see more white and less blue.

What makes a red sunset?

As the Sun gets lower in the sky, its light is passing through more of the atmosphere to reach you. Even more of the blue light is scattered, allowing the reds and yellows to pass straight through to your eyes.

Sometimes the whole western sky seems to glow. The sky appears red because small particles of dust, pollution, or other aerosols also scatter blue light, leaving more purely red and yellow light to go through the atmosphere.

Is the sky blue on other planets, too?

It all depends on what’s in the atmosphere! For example, Mars has a very thin atmosphere made mostly of carbon dioxide and filled with fine dust particles. These fine particles scatter light differently than the gases and particles in Earth’s atmosphere.

Photos from NASA’s rovers and landers on Mars have shown us that at sunset there is actually the opposite of what you’d experience on Earth. During the daytime, the Martian sky takes on an orange or reddish color. But as the Sun sets, the sky around the Sun begins to take on a blue-gray tone.

The top image shows the orange-colored Martian sky during the daytime and the bottom image shows the blue-tinted sky at sunset. Both images were captured by NASA’s Mars Pathfinder Lander. Credit: NASA/JPL

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Why Is the Sky Blue? Science of Blue Skies and Red Sunsets

Why is the sky blue? This is one of the classic small child questions that many adults answer with vague “just because” answers. The real reason the sky is blue because gas and dust in the atmosphere scatter blue light.

You’ve seen pictures of the sun taken from space, so you know it looks white or faintly yellow. You know the air in the atmosphere mainly looks clear and colorless, so you may be wondering why the sky looks blue. The answer has to do with the nature of sunlight and the composition of the Earth’s atmosphere.

Why the Sky Is Blue

Sunlight appears one color, but what you perceive as white light is really a mixture of colors. You can use a prism to separate light into its spectrum (the rainbow) to see this for yourself. When light enters the atmosphere the colors react differently to gas molecules and small particles in the air. Even though the atmosphere looks clear, it contains tiny particles of dust, ash, and water droplets. Shorter wavelengths of light, like violet and blue, are scattered by these particles. Scattering at a wavelength of 400 nm is 9.7 times more intense than scattering at wavelength 700 nm. This effect is called Rayleigh scattering after Lord Rayleigh, who described the effect.

Longer wavelengths, like orange and red, are not scattered as much by the particles. So, the overall appearance of a clear sky is blue.

Why the Sky Near the Horizon Is White

Near the horizon, you may notice the blue of the sky fade into a paler color or becomes white. This is because the Earth’s surface reflects back light. It reflects back pretty much all the colors of visible light, so you see white light.

The color of the sky around the sun also appears white, but this is due to a process called Mie scattering. Mie scattering does not depend so much on visible wavelength, so the overall effect is white light. Mie scattering is also responsible for the white appearance of fog and mist.

Why Sunrise and Sunset Are Orange and Red

The more atmosphere sunlight has to pass through before reaching your eyes, the more pronounced the effect becomes. At sunrise and sunset, light has to pass through the atmosphere at an angle before you see it. This means there is more air and more scattering. Nearly all the blue light is scattered, so you see more yellow, orange, and red. If there is dust or pollution, the color difference is intensified, so you could see a blood red sky and even the color of the sun may appear red.

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How to survive a nuclear attack, openmind books, scientific anniversaries, where are the earth’s real lungs, featured author, latest book, john tyndall, the man who explained why the sky is blue.

What’s the scientific question that children most often ask their parents? Given that today we have surveys on almost everything, they also exist on this topic , and there does seem to be one single question that is consistently repeated: Why is the sky blue? The data show that the vast majority of parents struggle to respond to an enigma solved a century and a half ago by a curious Irishman: the physicist John Tyndall.

Born in the small town of Leighlinbridge, the son of a policeman father and a mother disinherited for marrying him, Tyndall (2 August 1820 – 4 December 1893) is one of those rare scientists whose name arises unexpectedly in the thread of such disparate subjects that one comes to wonder if it’s the same person . Whether the topic is anaesthesia, the greenhouse effect, the sterilization of food, the first climb of Mount Weisshorn, the principles of fibre optics or the mystery of magnetic levitation, the same name pops up: John Tyndall.

Formally, the Irish scientist launched his career as a reputed physicist thanks to his studies on diamagnetism, the repulsion on which superconductors or magnetic levitation trains are based. These works earned him the appreciation of Michael Faraday , who became his mentor. However, perhaps his most original contributions were made in the field of radiant energy—later called infrared—of gases .

Demonstrated the greenhouse effect

It was this line that led him to discover the high infrared absorption of water vapour, thus demonstrating the greenhouse effect of the terrestrial atmosphere that until then had only been speculation. But these studies also led him down a peculiar path: by inventing an apparatus that measured the amount of CO2 exhaled by the human breath by means of its infrared absorption, he laid the foundations of capnography, the system that is used today to monitor the breathing of anesthetized patients or those in intensive care.

This was not Tyndall’s only incursion into biomedicine, nor the one that prompted the University of Tübingen to award him an honorary doctorate of medicine. Half a century before Alexander Fleming , he was one among several scientists who independently studied the bactericidal properties of the fungus Penicillium . His interest in the air, his main study material, led him to conserve boiled broths in a germ-free atmosphere, an experiment that escaped Louis Pasteur. And when bacterial spores contaminated his broths, he invented tyndallisation, the first method of food sterilization that killed these heat-resistant forms.

While his enthusiasm for mountaineering led him to make the first successful ascent of the Weisshorn and to lead one of the first teams to reach the peak of the Matterhorn, he entertained himself by studying the dynamics of the glaciers. And between one occupation and another, he still had time to practice another great passion: science dissemination. His books are among the best pioneering examples of the popularisation of science for a non-specialist audience . In his lectures to crowded auditoriums in Britain and the US, he marvelled his viewers by showing how a ray of light was diverted by a stream of water, the principle on which modern fibre optics is based.

The enigma of the blue sky

And Tyndall explained why the sky is blue. He did so in the 1860s at the Royal Institution in London where he served as professor of physics for 34 years. In the course of his research on the radiant energy of the air, he constructed a glass tube that simulated the atmosphere , with a source of white light at one end that acted as the Sun. Tyndall observed that, as he introduced smoke into the tube, the beam of light appeared bluish when looking at the side of the tube , but reddish looking from the end opposite the light source.

This phenomenon led him to propose that the particles of dust and vapour in the atmosphere scattered the blue light that came into our eyes. Today we know that blue is scattered more due to its shorter wavelength , while red penetrates more because it is the longest wave of visible light. As the distance that light travels through the air increases, as at dawn and dusk with the Sun low on the horizon, the blue light is absorbed before reaching our line of sight and we observe the scattering of the red

Curiously, Tyndall was actually wrong. The so-called Tyndall effect describes this phenomenon of dispersion in fine-particle fluids , but what we see in the sky is actually the so-called Rayleigh scattering caused by the air molecules themselves, which are much smaller than the wavelength of light (and not by the much larger dust particles). However, this is a technicality that does not take away from the fact that parents all over the world should be grateful for Tyndall’s genius.

Javier Yanes

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Why is the sky blue?

Asked by: Natalie Weaver (aged 11)

Robert Matthews

It’s often thought it’s because of light reflected back into the sky from the blue sea. In fact, it’s the result of sunlight being scattered when it strikes the air molecules in the atmosphere.

Sunlight is made up of – literally – all the colours of the rainbow, and the complex physics of how light interacts with molecules means shorter-wavelength blue light is more strongly scattered than red light. As a result, it is blue-coloured light that ends up spread most widely across the sky, dominating its appearance.

• Is there any truth behind the saying ‘red sky at night, shepherd’s delight’?
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Is "Why is the sky blue?" a philosophical question or scientific?

Why is "Why is the sky blue?" such a common question made by children? And why has that question about the question never been asked before?

Is it that the question is just a cultural artifact, that is, that someone remarked on one child somewhere actually asking that question once, and once written others pick up on the humor of such a deep philosophical question coming from someone so young, and then the humor being propagated through our current culture by the media?

Though many children do go through a 'why' stage, do most children go through this, if not verbally, at least psychologically? And is this cross-cultural?

As a side question, is the question "Why is the sky blue?" truly a question that can be answered by 'why'? Is it really asking for an event sequence description or is it misplacedly asking for a motivated causality (expecting of all events to be initiated by an actor)?

• philosophy-of-mind
• demarcation

• "Why is "Why is the sky blue?" such a common question made by children?" Is it? Or is that question just used as an illustration of the inquisitive mind of a child, the mind that asks plain questions about mundane things, comparing that to the adult mind that long since stopped reflecting over such mundane things. –  MichaelK Commented Aug 8, 2018 at 14:24
• Note that, to help direct answers, there are multiple ways of answers the "why is the sky blue?" question: the physical manifestation of Raleigh scattering, atmosphere composition, and EM frequencies emitted by the sun along with biological properties of retinal receptors and neuronal processing, or the metaphysical one of whether a color perceived by one person is the same as that perceived by another, or an other number of possibilities. This question is about the sky/blue question and what it means to be a 'why' question (also maybe child psychology). –  Mitch Commented Aug 8, 2018 at 14:25
• @MichaelK Didn't I ask refer to the question as a representative of inquisitiveness? But mundanity is surely relevant, and might appear in a more formal answer, but does that really answer my question? –  Mitch Commented Aug 8, 2018 at 14:34
• No it does not answer the question. I challenged the question. Is it really true that children ask "Why is the sky blue?" a lot, or is it only said that this is what children do a lot? –  MichaelK Commented Aug 8, 2018 at 14:36
• @MichaelK Do you think the idea of mundanity as you get older is a central part of the situation? Could you put that in an answer? –  Mitch Commented Aug 8, 2018 at 14:53

4 Answers 4

The sky being blue is something that we can all observe daily, but which does not seem to have a clear impact on our lives. So it's something that most adults have learned to take for granted and not question. Children, however, have a tendency to notice things that adults don't, and to ask questions about them. So "why is the sky blue?" is a plausible question for a child to ask.

Although modern science does have some explanations for this, it still stands as a paradigmatic example of a very familiar phenomenon for which most adults neither know nor seek an explanation.

As such, it's also a good stand-in for a philosophical inquiry, since many of those revolve around questioning familiar phenomena or assumptions that the majority of people take for granted.

• Hm... like kids, seeing things new (or realizing them) for the first time, where we've all been habituated to them and don't notice, makes them more skeptical than those with more experience? –  Mitch Commented Aug 8, 2018 at 19:34

As someone whose professional life revolved around science, I see this as a scientific question which is asking for an event sequence description. If I were a philosopher, I might think it was philosophical.

At least one of my kids asked that * , so it must not be a rarity (though that conclusion doesn't necessarily follow.)

* I remember having to look up the answer.

I think your question is a false dilemma, btw. Many young children ask questions simply for attention, to try to make a point, to hear themselves speak, etc. But that's the parent in me speaking. Answering in a realm outside of my common experience is difficult.

• This is my first thought, what about the light is making it blue (because sometimes, it is red like toward evening). And then maybe it's something about the processing of the eye and brain. But then I think maybe other people see green and I see green when they see blue (and it then becomes a question of philosophy about if color is a property of an object or of the eye or what). Or maybe it is about labeling or the arbitrariness of things. So I think there are lots of possible good answers. –  Mitch Commented Aug 8, 2018 at 19:29
• Also, there's a question about the purpose of language. Is it a coding mechanism to actually transfer information (like a mechanical description of biological pathways) or is it a social construct, to elicit a call and response pattern to augment in-group strength, or is it, like dreams, just mental processes being repeated in order to strengthen internal connections? –  Mitch Commented Aug 8, 2018 at 19:32
• I agree that labeling is a problem neurophysiologically. I can't see language as facilitation without purpose, though. It is believed by neurophysiologists (based on histopathology) that the most common form of schizophrenia is due to the lack of synaptic pruning (in effect, errant pathways are facilitated as well as correct ones.) But language may be a problem here between us. –  anongoodnurse Commented Aug 8, 2018 at 19:48
• As far as dreams go, I have no real understanding of them, so I can't say one way or another. I have my hypotheses, and I can find research that supports my hypotheses, but I know that that's just supporting my own bias. –  anongoodnurse Commented Aug 8, 2018 at 19:52
• If I think I understand what you mean by 'facilitation without purpose', there are lots of behaviors that are simply fashion, and many parts of language, because it is so arbitrary and non-representational, is fashionable/purposeless/artifice. Why do most shirt collars have that particular angle? Oh, many years ago most had another. Why do people in the US say elevator and not lift? Same reason (which is no reason at all just a description, which frankly was the motivation that got me to ask here, all the ELU questions about 'Why? Why? Why?' when it just is , there's no cause. –  Mitch Commented Aug 8, 2018 at 20:21

The English word "why" has several meanings, thus the question is ambiguous. Aristotle, for example, recognized four kinds of causation. What he would have called the "material" cause is Rayleigh scattering--the different bending of different colors of light in the atmosphere. There might be other material causes from different perspectives; for example, light of blue wavelengths stimulates receptors in the retina differently, and the brain interprets these in a certain way.

If the question is about agentive cause (i.e., "for what purpose"), then we must pre-suppose an agent--whose purpose? Or we might duck the need for an agent with an evolutionary explanation: we evolved a sense of sight with color perception that helped us distinguish the salient features of our world.

Children do indeed like to ask "why". They should be taught to be more specific. :-)

• Nice. Four causes . Also, there is the concept of Five why's which while not supposedly philosophical, does seem to be more reminiscent of the child's motivation (or at least the way adults tend to take it), which seem to hit any one of Aristotle's categories based on which verb was used in the previous answer to the child. Also, there is the problem of justification, which brings up the proof trilemma , circular, infinite, or axiomatic patterns. –  Mitch Commented Aug 8, 2018 at 19:17
• As to asking kids to be more specific, you'd think asking a question back would stop them, but no, they're better than that. "Dad, why is the sky blue?", "Well, do you mean operationally, or what purpose, or some other?" "Dad, why are you so defensive? Do you just not know?" –  Mitch Commented Aug 8, 2018 at 19:22

Who's on first. What's on second. I don't know is on third.

Above and beyond the ambiguity of language there is the ambiguity of human thought, even in a single individual. Put two humans in a room and have them talk and they will inevitably misunderstand both each other and themselves.

The question can be either, depending upon context, intent, cultural indoctrination, etc. In the most literal interpretation, I would argue that the nature of the question depends mainly upon what information the individual asking the question is seeking.

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Curious Kids: Why is the sky blue and where does it start?

Senior ARC Discovery Early Career Research Fellow, Monash University

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Duane W. Hamacher receives funding from the Australian Research Council.

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This is an article from Curious Kids , a series for children. The Conversation is asking kids to send in questions they’d like an expert to answer. All questions are welcome – serious, weird or wacky!

Why is the sky blue and where does it start? – Oliver Scott, age 7, Wombarra.

This is something that parents get asked every day. And it’s a great question, Oliver!

Some people think the sky is blue because of sunlight reflected off the ocean and back into the sky. But the sky is blue even in the middle of the countryside, nowhere near the sea!

Others think it’s because of the water in our atmosphere. But the sky is blue in places that are extremely dry, like the desert.

So what’s the real reason?

The sky is blue because of the way sunlight interacts with our atmosphere.

If you’ve ever played with a prism or seen a rainbow, then you know light is made up of different colours. The name “ROY G. BIV” helps us remember these colours: red, orange, yellow, green, blue, indigo, and violet.

These colours make up just a tiny portion of the electromagnetic spectrum, which includes ultraviolet waves, microwaves, and radio waves. This means the invisible waves that cause sunburns, allow us to heat-up our leftovers, and let us listen to the radio are all forms of light.

Light moves as waves of different lengths: some are short, making bluer light, and some are long, making redder light. As sunlight reaches our atmosphere, molecules in the air scatter the bluer light but let the red light pass through. Scientists call this Rayleigh scattering .

When the Sun is high in the sky, it appears its true colour : white. At sunrise and sunset, we see a much redder sun. This is because the sunlight is passing through a thicker layer of our atmosphere. This scatters the blue and green light along the way, allowing the redder light to pass through and illuminate the clouds in a beautiful array of red, orange, and pink.

Rayleigh scattering can affect how we see the Moon. When the Moon passes through the shadow of the Earth during a total lunar eclipse, blue and green light is scattered in the Earth’s atmosphere, letting red light pass through. Our atmosphere acts a like a magnifying glass, refracting (bending) the red sunlight onto the Moon. This can give it an eerie dark red hue.

For this reason, many cultures - including some Australian Aboriginal groups - associate lunar eclipses with blood.

Rayleigh scattering works on other planets, too. Did you know that the sky on Mars is also blue? (When there are no big storms kicking red dust into the air, that is!)

And finally, where does the sky start?

This is a tricky question. A bird flying 50 meters above us looks like it’s in the sky. But so do aeroplanes, and they fly more than 10,000 metres overhead.

“The sky” is just our atmosphere as we see it from underneath. A majority of our atmosphere extends about 16 km upward, and this is where most of the Rayleigh scattering happens.

If you’ve ever seen video of a rocket going into space, you can see the blue sky fade away to a black background as it climbs above the atmosphere.

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Why is the Sky Blue: Science Projects by Science Made Simple

Why is the sky blue - easy science projects.

These 3 fun and easy science projects will help you understand why the sky is blue and sunsets are red.

SAFETY NOTE: Please read all instructions completely before starting. Observe all safety precautions.

Table of Contents

• The Atmosphere
• Light Waves and Colors
• Why is the sky blue?
• Blackness of Space
• Red Sunsets
• Learn More: The Atmosphere
• Easy Reading

Project 1 - Split light into a spectrum

What you need:

• a small mirror, a piece of white paper or cardboard, water
• a large shallow bowl, pan, or plastic shoebox
• a window with direct sunlight coming in, or a sunny day outdoors

What to do:

• Fill the bowl or pan about 2/3 full of water. Place it on a table or the floor, directly in the sunlight. (Note: the direct sunlight is important for this experiment to work right.)
• Hold the mirror under water, facing towards the sun. Hold the paper above and in front of the mirror. Adjust the positions of the paper and mirror until the reflected light shines on the paper. Observe the colored spectrum.

What happened:

The water and mirror acted like a prism, splitting the light into the colors of the spectrum . (When light passes from one medium to another, for example from air to water, its speed and direction change. [This is called refraction, and will be discussed in a future issue.] The different colors of light are affected differently. Violet light slows the most, and bends the most. Red light slows and bends the least. The different colors of light are spread out and separated, and we can see the spectrum.)

Project 2 - Sky in a jar

• a clear, straight-sided drinking glass, or clear plastic or glass jar
• water, milk, measuring spoons, flashlight
• a darkened room
• Fill the glass or jar about 2/3 full of water (about 8 - 12 oz. or 250 - 400 ml).
• Add 1/2 to 1 teaspoon (2 - 5 ml) milk and stir.
• Take the glass and flashlight into a darkened room.
• Hold the flashlight above the surface of the water and observe the water in the glass from the side. It should have a slight bluish tint. Now, hold the flashlight to the side of the glass and look through the water directly at the light. The water should have a slightly reddish tint. Put the flashlight under the glass and look down into the water from the top. It should have a deeper reddish tint.

The small particles of milk suspended in the water scattered the light from the flashlight, like the dust particles and molecules in the air scatter sunlight. When the light shines in the top of the glass, the water looks blue because you see blue light scattered to the side. When you look through the water directly at the light, it appears red (like a sunset or sunrise) because some of the blue was removed by scattering.

Project 3 -Mixing colors

• a pencil, scissors, white cardboard or heavy white paper
• crayons or markers, a ruler
• a small bowl or a large cup (3 - 4 inch, or 7 - 10 cm diameter rim)
• a paper cup
• Use the bowl to trace a circle onto a piece of white cardboard and cut it out. With the ruler, divide it into six approximately equal sections.
• Color the six sections with the colors of the spectrum as shown. Try to color as smoothly and evenly as possible.
• Poke a hole through the middle of the circle and push the pencil part of the way through.
• Poke a hole in the bottom of the paper cup, a little bit larger than the diameter of the pencil. Turn the cup upside down on a piece of paper, and put the pencil through so the point rests on the paper on a table. Adjust the color wheel's position on the pencil so that it is about 1/2 inch (1 - 2 cm) above the cup.
• Spin the pencil quickly and observe the color wheel. Adjust as necessary so that the pencil and wheel spin easily.

The colors on the wheel are the main colors in white light. When the wheel spins fast enough, the colors all appear to blend together, and the wheel looks white. Try experimenting with different color combinations.

Learn more about colors using chromatography

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Why Is the Sky Blue?

Try this easy science experiment

• Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
• B.A., Physics and Mathematics, Hastings College

The sky is blue on a sunny day, yet red or orange at sunrise and sunset. The different colors are caused by scattering of light in the Earth's atmosphere . Here is a simple experiment you can do to see how this works:

Blue Sky - Red Sunset Materials

You only need a few simple materials for this weather project :

• Transparent container with flat parallel sides
• Flashlight or cell phone light

A small rectangular aquarium works well for this experiment. Try a 2-1/2-gallon or 5-gallon tank. Any other square or rectangular clear glass or plastic container will work.

Conduct the Experiment

• Fill the container with about 3/4 full of water. Turn on the flashlight and hold it flat against the side of the container. You probably won't be able to see the beam of the flashlight, although you may see bright sparkles where the light strikes dust, air bubbles, or other small particles in the water. This is much like how sunlight travels through space.
• Add about 1/4 cup of milk (for a 2-1/2 gallon container—increase the amount of milk for a larger container). Stir the milk into the container to mix it with water. Now, if you shine the flashlight against the side of the tank, you can see the beam of light in the water. Particles from the milk are scattering light. Examine the container from all sides. Notice if you look at the container from the side, the flashlight beam looks slightly blue, while the end of the flashlight appears slightly yellow.
• Stir more milk into the water. As you increase the number of particles in the water, the light from the flashlight is more strongly scattered. The beam appears even bluer, while the path of the beam furthest from the flashlight goes from yellow to orange. If you look into the flashlight from across the tank, it looks like it is orange or red, rather than white. The beam also appears to spread out as it crosses the container. The blue end, where there are some particles scattering light, is like the sky on a clear day. The orange end is like the sky near sunrise or sunset.

How It Works

Light travels in a straight line until it encounters particles, which deflect or scatter it . In pure air or water, you can't see a beam of light and it travels along a straight path. When there are particles in the air or water, like dust, ash, ice , or water droplets, light is scattered by the edges of the particles.

Milk is a colloid , which contains tiny particles of fat and protein. Mixed with water, the particles scatter light much as dust scatters light in the atmosphere. Light is scattered differently, depending on its color or wavelength. Blue light is scattered the most, while the orange and red light is scattered the least. Looking at the daytime sky is like viewing a flashlight beam from the side -- you see the scattered blue light. Looking at sunrise or sunset is like looking directly into the beam of the flashlight -- you see the light that isn't scattered, which is orange and red.

What makes sunrise and sunset different from the daytime sky? It's the amount of atmosphere the sunlight has to cross before it reaches your eyes. If you think of the atmosphere as a coating covering the Earth, sunlight at noon passes through the thinnest part of the coating (which has the least number of particles). Sunlight at sunrise and sunset has to take a sideways path to the same point, through a lot more "coating", which means there are a lot more particles that can scatter light.

While multiple types of scattering occur in the Earth's atmosphere, Rayleigh scattering is primarily responsible for the blue of the daytime sky and reddish hue of the rising and setting sun. The Tyndall effect also comes into play, but it is not the cause of blue sky color because molecules in air are smaller than the wavelengths of visible light.

• Smith, Glenn S. (2005). "Human color vision and the unsaturated blue color of the daytime sky". American Journal of Physics . 73 (7): 590–97. doi: 10.1119/1.1858479
• Young, Andrew T. (1981). "Rayleigh scattering". Applied Optics . 20 (4): 533–5. doi: 10.1364/AO.20.000533
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Night sky for tonight: Visible planets, stars and more in this evening's sky

The night sky is full of wonder, here's what to look out for tonight..

There is so much to see in the night sky tonight, here's what you can look forward to. 

A good telescope or pair of binoculars will help you see some of the night sky’s fainter objects. However, the unaided eye is enough to learn its stars and constellations , watch the moon , experience meteor showers and see satellites whizz across the night sky. 

Read on to find out what you can see in the night sky tonight, from planetary meet-ups to the ever-changing moon phases , meteor showers and more. Want to look even further ahead? Check out our monthly night sky guide our brightest planets guide also tells you what planets are visible and when this month. 

Track the ISS   |   Starlink satellite train   |   Moon viewing guide

WEDNESDAY AUG. 14 - COMPARE THE COLORS OF STARS

Bright stars in the summer night sky are a great skywatching target for those in the Northern Hemisphere. 

If you look at them long enough you should notice that they shine different colors. The color of a star is controlled by the temperature of its photosphere — the outer 'shell' which radiates light. 

The colors change blue to white to yellow to orange, as temperature decreases, with the coolest stars appearing red.

The three prominent stars of the Summer Triangle asterism in the eastern sky —Deneb, Vega, and Altair — are A-class stars that appear blue-white to the naked eye, with temperatures ranging from 7,500 to 10,000 Kelvin. In contrast, Arcturus , visible in the western evening sky, is an orange K-class giant star with a temperature of around 4,300 K. Meanwhile, the reddish Antares , the heart of the Scorpius constellation , is an older M-class star with a cooler surface temperature of 3,500 K.

After midnight local time, look for the very bright, yellowish Capella rising in the northeast. You can estimate the temperatures of dimmer stars by comparing their color to these bright reference stars.

TUESDAY, AUG. 13 - MOON AND ANTARES (EVENING)

Look to the south immediately after sunset, and you'll see a waxing gibbous moon, now more than half-lit, shining brightly. Look to its upper left, and you may spy Antares , a reddish star now at its best. It's the brightest star in the iconic constellation of Scorpius and about 555 light-years from the solar system . Squint at it, and you'll more easily notice its reddish hue. The later you look, the closer the moon and Antares will be. From the South Pacific, the moon will occult (block) Antares, according to In-The-Sky.org . — Jamie Carter

WEDNESDAY, AUG. 14 - JUPITER AND MARS IN CONJUNCTION (PRE-DAWN)

It will be worth getting up early for this, one of the closest conjunctions between planets this year. Visible in the southeast from about 2 a.m. local time until sunrise, Mars and Jupiter will get to just a third of a degree apart (a third of the width of your little finger held at arm's length). However, Jupiter, at magnitude -2.2, will be about 15 times brighter than Mars at magnitude +0.8. Although the two planets will appear at their closest this morning, it will be worth looking at the pair during the mornings before and after for a similar view. — Jamie Carter

MONDAY, AUG. 12 - PERSEID METEOR SHOWER (OVERNIGHT)

Early this morning, the peak of the annual Perseid meteor shower took place, but don't despair if you missed it because of work or bad weather. Although you won't get another chance to see 50-75 "shooting stars" in an hour — as was possible last night — it will be wise to look skywards late tonight (preferably after midnight early on Tuesday, Aug.13) if skies are clear for the chance of a healthy number of bright meteors . If you can't escape to truly dark skies, keep any artificial lights away from your direct line of sight because there's always a chance of seeing one or two particularly bright "fireballs." The later you look, the higher the shower's radiant in Perseus will be in the northeastern sky. — Jamie Carter 

You can also watch the Perseid meteor shower online for free with this livestream hosted by astrophysicist Gianluca Masi of the Virtual Telescope Project. The livestream will begin at  9 p.m. EDT on Aug. 12 (0100 GMT on Aug. 13).  

MONDAY, AUG. 12 - FIRST QUARTER MOON (EVENING)

Tonight, the moon 's eastern side will appear to be half-lit — its so-called first quarter phase — as it reaches its 90-degree angle away from the sun on its monthly orbit of Earth. Since a first-quarter moon always rises around midday and sets around midnight, it begins to bleach the evening night sky to make it more difficult to see stars (and "shooting stars" from the Perseid meteor shower). It's nevertheless a beautiful sight for the naked eye. — Jamie Carter

SUNDAY, AUG. 11 — MONDAY, AUG. 12: PERSEID METEORS PEAK (PRE-DAWN)

There's no better time to see  shooting stars  from the northern hemisphere than tonight. At its peak, the annual  Perseid meteor shower  can produce around 60 meteors per hour visible in the night sky. The radiant point (where the meteors will appear to emanate from) will be the  constellation Perseus , which will rise in the northeastern sky around midnight. 

Meteor showers can often be marred by strong moonlight, but not so the Perseids this year since the First Quarter Moon will set around midnight. Look skywards during the early hours of Monday for the best chance of shooting stars, though light pollution and the clarity of the sky will make a huge difference. If you can, get away from light pollution — at least 40 miles from a major urban area is wise — but wherever you watch from, make sure you don’t have any artificial lights in your line of sight. Sit back, relax in a lawn chair, keep warm, and take regular breaks. Never look at your smartphone; its white light will ruin your eyes' dark adaption, which takes about 20 minutes to cultivate and just a single second of white light to ruin.

If you cannot look for Perseids in person, you can watch them live online here on Space.com courtesy of the Virtual Telescope Project. The  first  livestream will begin at  9 p.m. EDT on Aug. 11 (0100 GMT on Aug. 12,)  the  second  will begin at  9 p.m. EDT on Aug. 12 (0100 GMT on Aug. 13)  coinciding with the anticipated peak activity of the Perseid meteor shower.

FRIDAY, AUG. 9 — SATURDAY, AUGUST 10 - CRESCENT MOON, SPICA, ANTARES AND THE MILKY WAY (AFTER SUNSET)

About a quarter of the moon's Earth-facing side is now lit by the sun. Across two nights, it will appear on either side of Spica.  Arcturus  in the constellation  Boötes  will appear directly above the pair, while to the south, the  Milky Way  will rise after dark. However, to see the arc of our galaxy, you'll need to be well away from light pollution. -- Jamie Carter

THURSDAY, AUG. 8 — CRESCENT MOON, VENUS AND SPICA (AFTER SUNSET)

Here's another chance to see the crescent moon dominating the post-sunset evening sky, with Venus shining stubbornly close to the western horizon. Look at the moon's dark left side. Can you make out any details? Since no sunlight shines directly on it, it should be dark, right?

The light you can see is called "Planet-shine," "Earthshine," or "Da Vinci Glow." It's sunlight shining on  Earth  and reflecting onto the moon. It's easiest to see in a crescent moon a few days old. -- Jamie Carter

WEDNESDAY, AUG. 7 — CRESCENT MOON, VENUS AND SPICA (AFTER SUNSET)

A brighter, more obvious crescent moon will tonight be positioned about halfway between Venus, to its lower right, and bright star Spica, to its upper left. One of the 20 brightest stars in the night sky, Spica is the brightest star in the constellation Virgo .  -- Jamie Carter

Watch a Perseid fireball light up the skies above Macedonia in this striking video

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More From Forbes

Microsoft update warning—70% of all windows users now at risk.

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This is dangerous—70% of all Windows users face an impending security nightmare.

Updated August 6 with new key-logging warnings for Windows users.

This has not been a good few weeks for Microsoft. Fresh from the Recall recoil, CrowdStrike struck, with various ups and downs with Copilot momentum in between. But the constant throughout has been an impending security nightmare for the vast majority of its Windows users, now just months away.

We’re talking Windows 10, of course, and the staggeringly painful campaign to warn hundreds of millions of holdouts that they need to upgrade to Windows 11. Back in June, I reported on the latest Microsoft nag —a full-screen warning that “end of support for Windows arrives on October 14, 2025; this means your desktop won’t receive technical support or security updates after that date.”

If there was any doubt as to the real danger in leaving Windows unprotected, then Monday’s US government warning should quickly change minds. A 2018 Windows vulnerability has been added to its Exploited Vulnerability ( KEV ) catalog. “Microsoft COM for Windows,” CISA warns, “contains a deserialization of untrusted data vulnerability that allows for privilege escalation and remote code execution.”

Users have been given until August 26 to patch or cease using Windows systems. Clearly, this 2018 vulnerability does not impact Windows 11, nor any other Windows system updated in the last six years. The Windows 10 risk, though, is real.

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The prompt for CISA’s warning appears to be an August Cisco Talos report claiming that a Chinese hacking group with links to the country’s Ministry of State Security may have successfully exploited CVE-2018-0824 as part of an attack on a government research center in Taiwan. The center was “likely compromised,” Talos says.

“APT41 is a prolific and dangerous threat actor that all users and cybersecurity practitioners should be keeping track of,” Talos warns . “APT41 created a tailored loader to inject a proof of concept for CVE-2018-0824 , a remote code execution vulnerability in Microsoft COM for Windows, directly into memory to achieve local privilege escalation… Users should ensure all Windows systems are up to date to the latest version to protect against this vulnerability.”

If CVE-2018-0824 and APT41 all sounds a bit niche and unlikely to target your own Windows PC at home, then SnakeKeylogger is quite the opposite. The Register warns that “criminals are preying on Windows users yet again, this time in an effort to hit them with a keylogger that can also steal credentials and take screenshots.”

“Its arsenal includes keystroke logging, harvesting credentials, and capturing screenshots,” Fortinet ’s security research team warned this month of the SnakeKeyLogger trojan threat to Windows users. “Based on the FortiGuard telemetry, there were hundreds of 0-day detection hits. Moreover, the sites that the trojan connects to were queried several times which suggests infection.”

Windows 10 Vs Windows 11, July 2023-July 2024

While this hasn’t surfaced into a full scale zero-day warning as yet—more variations on a theme, it’s yet another reminder as to potential Windows vulnerabilities if the OS is not tightly managed. SnakeKeylogger targets users by way of malicious downloads, shared over email through phishing campaigns.

Back in 2022, Check Point Research warned that SnakeKeyLogger “is usually spread through emails that include docx or xlsx attachments with malicious macros, however this month researchers reported that SnakeKeylogger has been spread via PDF files. Users are advised to maintain good antivirus software and attachment scanning, as well as to beware the attachments the download and open to keep safe.

Putting aside CVE-2018-0824 being woken from the dead and the much more current SnakeKeyLogger RAT, the real challenge for many Windows 10 users is more one of hardware than the softer UI side of their Windows OS. If their machines are not suitable for Windows 11—as many are not, then they find themselves in an upgrade trap, having to buy new hardware for no ostensibly good reason other than Windows 10 coming off support. This becomes a resentful purchase to say the least.

But we are where we are. Windows hasn’t changed its stripes, and nor has Microsoft’s approach. The threats disclosed this week are serious in themselves, but they’re also further good examples as to why the prospect of hundreds of millions of Windows users heading towards end-of-support is a security nightmare.

Maybe, just maybe, users are now starting to listen—albeit not enough, not nearly fast enough. As Windows specialist Neowin has just reported, “in July 2024, Windows 11 hit an important milestone: for the first time since its launch in October 2021, the operating system crossed the 30% market share mark.” Just. With the latest stats from Statcounter showing better than 7% year-over-year growth for Windows 11.

But that means that more than twice as many Microsoft Windows users are still not using Windows 11 than those that are. Even now. Three-years post launch.

Window 11 isn’t at all new, and all those converts and non-converts know its pros and cons; so setting aside a Copilot AI-driven boost, the question is whether this is a trend or a blip. Certainly, when you look at Statcounter’s Windows 10 chart decline over the last year (above), the line chart is not something you could ski down. Similarly, Windows 11 growth is an easy stroll up a gently slope, to put it mildly.

And so, while it’s clearly good news that there’s some movement, the reality looks worrying. There will be some accelerated shifting to Windows 11 in the coming months ahead of their October 2025 end-of-life, and there will be some companies and home users (when it’s available) taking up extended paid support. But there will also be many millions of users coming off support and taking the risk. With plenty of headlines fueling the reluctance, this problem isn’t going away ( 1 , 2 , 3 ).

Take a look at Reddit or even the comments to this article and you’ll see the large body of Windows users opinion that is waiting for Microsoft to pull a late rabbit from the hat and extend Windows 10 support. Quite how that will land with all those who have made the investment to upgrade remains to be seen.

Given the experience of recent weeks, with those global images of blue screens of death all around, come next October, this could be a hackers’ paradise for some time at least. The other factor that will play will be bad actors taking advantage of the bad situation and mailing out scam after scam to target worried Windows 10 users.

Expect to see plenty of that through 2025.

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When is the next full moon? August's blue moon will be a supermoon, here's when to watch

Next week's August full moon will also be the first supermoon of the year, and yes, the sturgeon moon is as fishy as the name implies.

The sturgeon moon will also be a blue moon, but yet, it will actually appear red like a ball of fire in the night sky.

So, we’re in for a blue-red-sturgeon-supermoon this month.

Here's what it all means.

When is the full moon in August 2024?

The next full moon will be on Monday, Aug. 19, 2024 with peak illumination at 2:26 p.m.

The moon will first appear to be full in the afternoon on August 18 and will continue to appear full until August 20 around 2:30 p.m.

Why is August's full moon called the sturgeon moon?

The sturgeon moon is named after the gian fish because they were abundant and easy to catch in the Great Lakes during late summer.

According to the Old Farmer's Almanac , the sturgeon moon is directly related to giant-sized, lake sturgeon, a North American freshwater fish that was common throughout the Mississippi River Basin, the Great Lakes and in Lake Champlain. It was once considered an important food staple for Native American tribes and the settlers that lived in the region, but have become quite rare due to overfishing.

The most common sturgeon found in the Great Lakes is lake sturgeon, which can grow over 6 feet long and weigh around 200 pounds.

What's the best time to view the sturgeon moon?

On the evening of Aug. 19, look toward the southeast after sunset and you can watch the view of the sturgeon moon rising. It will look bigger and brighter than the usual full moons because it will be the first supermoon of the year.

To check for the moonrise and moonset times near you, click here .

What is a supermoon?

A supermoon happens when a full moon's orbit is closest to the Earth at the same time the moon is full. According to NASA , at approximately 226,000 miles from Earth, the full moon appears brighter and larger than a regular full moon, hence the term, supermoon.

Why is the blue moon red?

A seasonal blue moon is the third full moon in a season that has four full moons. In the summer of 2024, the full moons occur on June 21, July 21, August 19, and September 18. Therefore, the full moon in August, being the third in this sequence, is referred to as a blue moon.

The moon will not be blue, but on rare occasions, it can appear blue when viewed through tiny particles in the atmosphere, which are typically smoke and dust that filter out longer wavelengths of colors like red and yellow.

However, the haze created by summer heat and dry conditions of August, can lead to the illusion of a red hue to this month's sturgeon moon. According to the Farmer's Almanac , it is sometimes referred to as the red moon.

When is the next full moon?

The next full moon , the harvest moon, will occur on Tuesday, Sept. 17 at 10:34 p.m.

Maria Francis is a Pennsylvania-based journalist covering trending topics across the Mid-Atlantic region.

To revisit this article, visit My Profile, then View saved stories .

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Supplements Companies Are Cashing In on the Ozempic Wave

The supplement industry has a long, tangled history with the world of weight-loss products. Prior to the age of Ozempic , many of the trendiest diet aids were supplements, not prescription medications: green tea extract, caffeine pills, ephedra. According to the US National Institutes of Health, more than 15 percent of adult Americans have tried a weight-loss supplement. Now, the supplement industry is leaning into the GLP-1 boom. They can’t sell Ozempic—but they’re hitching a hefty wagon to it anyway, spinning up entire businesses built around existing demand for this blockbuster drug, or something like it.

Two different types of supplements are glomming onto the popularity of GLP-1 agonist drugs like semaglutide and tirzepatide, which mimic a natural appetite-suppressing, blood-sugar-regulating hormone called glucagon-like peptide-1. (Ozempic is one of the most well-known brand names for semaglutide.) First, there’s a rise in efforts to market supplements as complementary to GLP-1 drugs. The online storefronts for large supplement retailers like the Vitamin Shoppe and GNC now offer separate sections devoted to selling products to take in tandem with prescription meds. “GLP-1 Side Effects? Get Support for Your Journey,” the GNC website proclaims. The Vitamin Shoppe offers actual GLP-1 drugs through a partnership to launch a telehealth company, as well as more traditional supplements it markets as “nutrient support,” including probiotics, fiber, and multivitamins.

Brian Tanzer, the Vitamin Shoppe’s director of scientific and regulatory affairs, says that the company offers products that will compensate for the nutritional deficiencies that can arise when people taking GLP-1 drugs cut calories. “Current data shows that a significant percentage of the population does not meet their daily requirement for several nutrients, and this may be exacerbated by a drastic reduction in calorie intake because of the use of GLP-1 medications,” he says.

Food and supplement giant Nestlé is getting in on the action, too. In addition to launching an upcoming line of foods aimed specifically at people who take GLP-1 medications, the company also launched a website, GLP-1nutrition.com, selling a variety of supplements to “complement your GLP-1 journey.” “We are the first major food company to enter this space,” Nestlé external communications lead Dana Stambaugh told WIRED via email. Meanwhile, meal delivery services have also started courting GLP-1 patients. Daily Harvest offers a “GLP-1 Support” bundle of meals designed to appeal to people on these medications; a smaller service called BistroMD peddles similar fare .

While GLP-1 drugs are remarkably effective, they often also cause side effects like gastrointestinal distress and muscle loss. Side effects can be severe enough that people stop taking the medications. A recent study from the Blue Cross Blue Shield Association found that over half the people it surveyed who had been prescribed these drugs in the past decade stopped taking them within three months.

Obesity medicine physician Alexandra Sowa recently launched a line of supplements aimed at people taking GLP-1 meds. “I was cobbling together what I could find out on the market to meet the needs of my patients,” she says. “Nothing has been made just for the GLP-1 user.” Sowa, who still runs her Manhattan-based practice, says the goal is to keep patients comfortably on the medications by helping to alleviate side effects. Her system sells three powdered supplements (electrolytes, protein, and fiber) that can be purchased together or separately; they were designed to appeal to the tastebuds of people on GLP-1 meds, who might not tolerate sweet products as they once did.

The other type of Ozempic-adjacent supplement on the rise right now is positioned not as a helpmeet to pharmaceutical offerings but instead as an alternative. These products often have “GLP-1” in their name, signaling to potential customers who are familiar with the prescription medications that they offer something in the same universe. A brand called Supergut touts prebiotics as “nature’s Ozempic” in its marketing and claims that its products “trigger your body’s hunger-quieting GLP-1 hormone naturally.” The supplement brand Pendulum offers a “GLP-1 Probiotic,” which it also claims helps increase GLP-1 production “naturally.” Other lines, like Codeage, offer blends like the “GLP Advantage+,” which contains L-taurine, decaffeinated green tea leaf extract, boron, prebiotics, and a variety of other ingredients, including berberine , an antibiotic-like ingredient popular with wellness influencers on TikTok who tout its appetite-suppressing properties. When asked if Codeage intended the product as an alternative to GLP-1 drugs for people who don’t want to take prescription drugs, cofounder Auggie Quancard said it was “designed for individuals interested in supporting their metabolic health.” (Codeage also offers a product the company says is to be taken in tandem with GLP-1 drugs.)

These products and the companies selling them are already seeing rising profits from interest in the GLP-1 boom. The Vitamin Shoppe reported an increase in “sugar control” categories of supplements, particularly berberine—sales were up nearly 40 percent in 2023 across the whole category, and berberine sales jumped 50 percent. Supergut CEO Marc Washington told WIRED that the company’s sales in 2024 were three to four times previous years’ sales as a result of increased interest in non-pharmaceutical ways to increase GLP-1 production.

Some health experts question whether these offerings are worthwhile. “Both of these categories of supplements are very opportunistically taking advantage of the lax laws around supplements to jump in and try to profit from a group of medications that are truly effective,” says Pieter Cohen, an associate professor of medicine at Harvard Medical School who studies supplements. Compared to conventional drug products, supplement regulation—and enforcement of those regulations—is markedly lax . While drugs require approval from the Food and Drug Administration before hitting the market, supplements do not. In fact, the FDA cannot force supplement-makers to conduct premarket testing to demonstrate that their products contain what they say they contain. The regulatory environment is often described as a wild west.

When asked directly, many complementary-supplement purveyors will acknowledge that evidence is limited. “At the present time, controlled human studies on the benefits of supplement support for GLP-1 users are not available,” the Vitamin Shoppe’s Tanzer says.

Alternative GLP-1 supplements, too, face skepticism about their claims. Molly Natchipolsky, a spokesperson for the National Center for Complementary and Integrative Health, told me via email that the NCCIH’s research team studying natural products is “not aware of any supplement that can have similar effects or mechanisms to current GLP-1 agonists.”

One reason why GLP-1 agonist drugs work so well is because they increase the presence of the hormone in the body for a prolonged period of time. While there are substances known to naturally increase GLP-1 in the body, they can only do so for a short period of time. “No matter how much GLP-1 you get your intestines to produce, it’s never going to be as effective as the Ozempic you’re taking,” says Frank Duca, a University of Arizona assistant professor who studies metabolic disease. A fiber or probiotic supplement can increase your GLP-1 levels, he says, “but it’s not going to work like Ozempic.”

Duca is concerned that the marketing claims made by some of the supplements purporting to provide alternatives to GLP-1 drugs may be dubious, and he worries they will set back how research is received. “It’s so scary,” he says. “The field is very close to making some really good headway in metabolic disease, but now you have so many startups seeing how well Ozempic is doing and saying, ‘This is just like Ozempic.’ It’s really not.”

Some of the alternative supplement purveyors themselves say they agree that the two are not really comparable. “If you’re just talking in terms of absolute impact, there is no supplement or food or beverage or, frankly, other forms of pharmaceutical anywhere close to as effective at weight loss as these GLP-1 drugs,” says Supergut’s Washington, despite the conspicuous “nature’s Ozempic” branding his company uses.

Still, Washington believes his products offer smaller-scale benefits for people who want improved digestive health but don’t want, or don’t meet the medical criteria, for prescription drugs. “We specifically chose unique prebiotics that have clinical evidence around appetite control, blood sugar control, and GLP-1.” Indeed, in addition to drawing on other studies on prebiotic fibers, Supergut ran its own double-blind, placebo-controlled clinical trial , which is not yet common in this corner of the industry. It found that taking Supergut’s prebiotic shakes helped regulate blood sugar better than placebos in the study participants. “Many people will call this a gold-standard clinical study.”

Not everyone, though—even a study like this is subject to scrutiny from some experts. Gregory Lopez, the research lead at the supplement and nutrition database Examine.com, sees Supergut’s study as “a bit weak” in the way it was designed. Overall, he finds it “suggestive, but not definitive.” (Supergut’s Washington defends his study as rigorous: “It was significant and compelling enough to pass a peer review and publication for a leading medical journal,” he tells WIRED.)

Lopez takes a skeptical stance toward this new category of supplement sold with “GLP-1” branding—and, indeed, supplements sold for weight loss and weight management in general. “I don’t trust weight-loss supplements,” he says. “Maybe they’ll work a little bit but not a whole lot. They’re not going to be life-changing compared to things that we know actually work.”

Life-changing or not, as long as demand for GLP-1 drugs stays booming, the supplement industry is unlikely to curb its appetite for adjacent products.

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Money blog: Coca-Cola launching new flavour in collaboration with popular biscuit - and fans are divided

Welcome to the Money blog, a hub of personal finance and consumer news. Our focus has been on inflation rising - while other posts include Coke launching a new flavour with Oreo. Leave a comment on any of the stories we're covering in the box below - we round them up every Saturday.

Wednesday 14 August 2024 16:35, UK

• UK inflation rises for first time since December - analysis
• Wizz launches unlimited flight package for £445 - but there's a catch
• Coca-Cola launching Oreo drink - and fans are divided

Essential reads

• Is this the end of the British pub?
• What's gone wrong at Asda?
• Best of the Money blog - an archive of features

Tips and advice

• TV chef picks best cheap eats in London
• Save up to half price when visiting top attractions with this trick
• 'I cancelled swimming with weeks of notice - can they keep my money?'

Ask a question or make a comment

John Lewis is looking to cut 153 jobs as part of a staff shake-up across its stores. 

The high street giant claims the proposals are designed to improve customer service, ensuring workers are "in the right place, doing the right tasks at the right time". 

It is hoping the job cuts will be through voluntary redundancy and natural attrition - which covers people leaving through retirement, resignations or moving job. 

Staffing changes will also see currently separate roles for serving front and back of house combined.

John Lewis is also investing £5m in digital headsets for store workers to communicate better with one another - in a bid to improve service.

The changes, which were announced to staff yesterday, follow a similar staffing overhaul at sister business Waitrose.

A spokesman for John Lewis said: "We're seeking to make sure partners are in the right place at the right time to help customers.

"We're also removing unnecessary tasks and introducing new technology to make their roles easier.

"We carried out similar changes in Waitrose earlier this year, with customer and partner feedback increasing significantly since.

"It's since been ranked the number one supermarket for customer satisfaction."

Coca-Cola is launching an Oreo-flavoured drink in collaboration with the biscuit manufacturer.

The limited edition, zero-sugar drink will be released from September in a black and white can containing what Coca-Cola describe as "flavourful hints inspired by Oreo cookies".

At the same time, Oreo will release a Coca-Cola flavoured biscuit.

Eugenia Zalis, global head of marketing for Oreo-maker Mondelez International, said she "cannot wait to see the reaction" from customers - but they're already coming in before the products have even hit the shelves.

Multiple X users were quick to deploy the Jurassic Park meme inspired by Jeff Goldblum's character, Ian Malcolm: "Your scientists were so preoccupied with whether or not they could, they never stopped to think if they should".

Another added: "I will happily eat Oreos while drinking a Coke Zero, but I don't want either of these things."

Others were more enthusiastic, simply writing: "Need."

Ms Zalis was confident about the collaboration, saying: "We have truly upped the ante."

The beverage will be available at major retailers and Pizza Express, Popeyes and Slim Chickens, Coca-Cola said.

By Daniel Binns, business reporter

Annual inflation in the US fell to 2.9% in July, down from 3%, according to official data released this lunchtime.

The announcement helps pave the way for the US Federal Reserve for cut interest rates next month.

This matters to monetary policy makers in the EU and UK as they don't like to be too misaligned with the US - for fear of impacting currency strength, among other reasons.

The annual consumer prices index (CPI) rate for July was the lowest since March 2021 and came in below market expectations.

In the immediate aftermath of the publication of the latest figures, financial markets upped their expectations that the Fed would cut interest rates by 0.25 percentage points, pricing in the likelihood of such an outcome at 60.5%. 

The likelihood of a bigger 0.5 percentage point cut was judged to be 39.5%.

Earlier in the day, the likelihood of a 0.25 or 0.5 percentage point cut had been almost 50-50.

The first increase in inflation this year is less a reason for panic than a signal that, after almost three years of wild volatility, the UK's measure of price increases is returning to a period of what looks far more normal fluctuation.

The primary reason CPI stepped up to 2.2% in the year to July is statistical, the base effect of energy prices falling less this year than they did in July 2023. A year ago the Ofgem retail price cap fell by more than £1,100, 10 times more than the £110 reduction last month. That means that while energy prices are lower than they were, annual inflation increased.

The Bank of England had forecast this move upwards from its target rate of 2% and used it to justify its cautious tone around interest rates, even as they were cut earlier this month for the first time since the hiking cycle began.

Below the headline rate of CPI were numbers that will give the Bank some confidence that it can afford to cut rates further by the end of the year.

Core inflation, a measure that removes volatile food and energy prices and indicates the underlying "secondary" effects of inflation, fell slightly from 3.5% to 3.2%. 

Goods inflation remains in negative territory at minus 0.6%, but that was an increase from minus 1.4% the previous month, driven in part by food inflation, which increased to 1.8% after 15 consecutive monthly falls. 

Inflation in services, which make up the majority of the British economy, fell to 5.2%. Coming a day after wage inflation also eased, that fuelled expectations that further rate cuts are coming, though not necessarily at the next Bank of England meeting in September. 

Market expectations of a cut in September rose to 45%, meaning a narrow majority expect rates to be held at 5%, with the prospects of further cuts before the year-end priced at 90% in November and 97% in December.

Watch Kelso's TV analysis here...

Every Wednesday we ask top chefs to pick their favourite Cheap Eats where they live and when they cook at home. This week we speak to TV chef Judy Joo, who co-owns the popular Seoul Bird in London.

Hi Judy, can you tell us your favourite places in London where you can get a meal for two for less than £40?

Since 1900,  Paul Rothe & Son  in Marylebone has been crafting some of the best sandwiches in London. Lucky for me, I live just around the corner from this charming, historic deli. 

My go-to is their famous pastrami and cheese, piled high with pickle, mayo, and mustard. Occasionally, I'll switch things up with their epic coronation chicken, or if I'm feeling adventurous, a jacket potato with tuna and sweetcorn. It's quintessentially British, and I love it. 

Trejo's Tacos has crossed the pond, opening its first international outpost in Notting Hill. Founded by actor Danny Trejo, this canteen boasts a cult following in Los Angeles (myself included) and has quickly become my favourite spot for tacos in London. 

My usual order includes a plate of Baja fish and spicy shrimp tacos, dosed in their house hot sauce and perfectly complemented by one of their stellar OG margaritas or homemade horchata. I also love their house-made guacamole and salsa served with their truly addictive freshly fried corn tortilla chips. I just munch away while thinking of the southern California sun. 

I live near Edgware Road, an area renowned for its vibrant Middle Eastern community and fantastic cuisine. Maroush , a London institution with multiple venues across the city, remains a favourite, especially the original one on Edgware Road.

The chicken or lamb shawarma is the star dish, slow-cooked on vertical rotisseries, infused with aromatic spices, and expertly sliced off with sabers. It's the perfect late-night snack after a few too many pints. I love their tomato okra stew with rice - so comforting and warming. 

Tucked away in the basement of an unassuming British pub down a quaint mews street in Marylebone is Liu Xiaomian . 

I usually order the minced pork xiaomian - toothsome wheat noodles swimming in a red chilli broth, then dressed with seasoned pork and fragrant spring onions. The numbing pork wontons are another standout, delivering what their name promises in true mala style. Don't miss the cucumber side salad which offers a refreshing respite for your palate.

What is your go-to cheap eat to cook at home when you have a night in?

My go-to budget-friendly meal for cooking at home is pimped-out instant ramen noodles. 

If I am feeling spicy, I'll grab a pack of Shin Ramen and add fresh veggies and leftover proteins from the fridge. 

Spinach, mushrooms, corn, spring onions, leftover roasted chicken, and some frozen dumplings usually make their way into the pot. Absolutely anything goes!  

And, to finish, I'll crack an egg in and let it cook on top of the noodles just until the yolk is set, but still gooey. It's a quick, delicious meal that hits the spot every time.

We've spoken to lots of top chefs - check out their cheap eats from around the country here...

By Sky News Data and Forensics Unit

As we've discussed throughout the morning, the rate of inflation grew to 2.2% in July - the first time since December last year that it has increased.

Which shop prices are increasing fastest?

Olive oil costs nearly two fifths more than it did last year, with prices for 500ml-1 litre rising from £6.39 to £8.83 in just 12 months.

The Money blog looked at the reasons why here...

Plums, meanwhile, are up by a quarter, from £3.08 per kilo to £3.57.

Food and drink products are responsible for seven of the 10 highest increases since last year.

For fans of a slicked-back hairstyle, non-food items like hair gel increased by a third, and for any pet owners, the price of a small mammal cage nearly hopped up by a fifth.

Top five price rises:

• Olive oil (500ml-1litre): up 38%, £6.39 to £8.83
• Hair gel (150-200ml): up 33%, £3.08 to £4.10
• Plums (per kg): up 25%, £2.85 to £3.57
• White potatoes (per kg): up 20%, 74p to 89p
• Cauliflower (each): up 20%, £1.07 to £1.28

Fifty-six of the 156 types of food and drink tracked by the ONS have actually become cheaper since last year. Many of these were store cupboard staples like pulses, dried pasta, and canned tomatoes.

Top food price decreases:

• Pulses (390-420g): down 13%, 77p to 67p
• Frozen prawns (per kg): down 8%, £18.77 to £17.24
• Cheddar cheese (per kg): down 8%, £9.49 to £8.77
• Spreadable butter (500g): down 7%, £4.18 to £3.90
• Frozen berries (per pack): down 6%, £2.53 to £2.37

Of non-supermarket items, electric heaters have been some of the biggest price fallers - by 22%.

How much has your individual spending changed in the last year?

Use our calculator to see how much prices are rising on the groceries, clothing and leisure activities you pay for...

We've had some more ONS data this morning - this time on house and rent inflation.

While the figures are largely unchanged from a month ago, the rental stats in particular are worth outlining as they illustrate the difficulties still facing renters.

Official data shows:

• Average UK private rents increased by 8.6% in the 12 months to July 2024, unchanged from in the 12 months to June 2024;
• Average rents increased to £1,319 (8.6%) in England, £748 (7.9%) in Wales, and £965 (8.2%) in Scotland;
• In Northern Ireland, average rents increased by 10% in the 12 months to May 2024;
• In England, rents inflation was highest in London (9.7%) and lowest in the North East (6.1%).

On the housing market, we learned:

• Average UK house prices increased by 2.7%, to £288,000, in the 12 months to June 2024 - unchanged from a month before;
• Average house prices increased in England to £305,000 (2.4%), in Wales to £216,000 (1.8%), and in Scotland to £192,000 (4.3%).

By Sarah Taaffe-Maguire , business reporter

News of an increased rate of price rises was welcomed by UK markets but it hit the pound. 

While inflation has increased, the fact the figure came in lower than expected could be a boost to the mainly UK-based companies that make up the FTSE 250, which rose 0.47% on the news, as did the 100 most valuable companies on the exchange, the FTSE 100. 

The pound, however, fell from its highest since late July and now £1 buys $1.2838 and €1.1659. 

Energy costs remain elevated with the benchmark oil price $81 for a barrel of Brent crude oil. 

Gas prices are still below the 100p a therm (the measurement for heat) high seen on Monday evening but not by a whole lot at 96.65p a therm. 

The biggest riser of FTSE 250 companies was gambling tech company Playtech.

Following Sky News reporting that gambling giant Flutter is in talks to buy the consumer arm of Playtech for £2bn, its share price shot up 13.57%.

Wizz Air has launched Europe's first unlimited flight package - but there are a few things you should know before signing up. 

The All You Can Fly membership costs £534 for 12 months, and is currently on sale until tomorrow for £445. 

Subscribers can use the deal to travel to more than 800 destinations as many times as they like over the course of a year, starting from 25 September. 

Here's the catch - customers must book the flights within 72-hours of them taking off. 

Each flight also comes with a £9 booking fee, which must be paid in addition to the membership. 

And, the costs of booking a seat and adding luggage is also not included. 

On the Wizz Air website, a "seat protection fee" ranges from ‎€80 (£68.31)  to ‎€100 (£85.39), and adding a bag costs between €11 (£9.39) and ‎€120.50 (£102.89). 

It's also important to note that there are only 10,000 memberships available. 

Wizz Air's commercial officer Silvia Mosquera said: "We are thrilled to be the first to introduce this one-of-a-kind membership for travellers in Europe. 

"The Wizz All You Can Fly membership will give customers hundreds of spontaneous travel options for a fixed price, giving them freedom to fly whenever is convenient without paying extra."

You can read all the terms and conditions of the All You Can Fly package here .

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