Latest news with #RayleighScattering
Yahoo
4 days ago
- Climate
- Yahoo
ASK A MET: How wildfire smoke turns the sky an eerie red
Ever wonder why the sky is blue on a clear day, but red when there are pollutants such as smoke in the air? Wildfire smoke fills the air with tiny particles. The particles, such as soot, ash, and other aerosols, are much larger than the gas molecules in the atmosphere. DON'T MISS: In simple terms, the skies turn red from wildfire smoke due to how the air particles in the smoke scatter sunlight. That is due to two processes called Rayleigh scattering and Mie scattering. Rayleigh scattering happens when light hits very small particles, much smaller than the wavelength of light (like oxygen or nitrogen molecules in the air). This process scatters shorter wavelengths more like blue and purple, much longer than red. That is why the sky looks blue. Mie scattering occurs when light encounters larger particles, like smoke, dust, pollen or water droplets. These particles are about the same size or larger than the wavelength of light. This process scatters all wavelengths more equally, not favouring blue like Rayleigh does. This leads to whiter or greyer appearance in the sky, especially when it's hazy. It can also make the sun look milky or red, especially during wildfire smoke events. Light hitting smoke or fog gets muddled, everything's scattered evenly, and you lose the vibrant blues––leaving warmer tones like red and orange. Under normal conditions, our sky appears blue because tiny air molecules scatter shorter wavelengths of light—like blue—more effectively than longer ones. But when wildfires fill the atmosphere with smoke, the story changes. Smoke particles are much larger than air molecules, so they scatter light differently. Instead of favouring short blue wavelengths, they scatter all wavelengths more evenly. However, they also filter out much of the blue and green light. What remains are the longer wavelengths––reds and oranges––that pass through more easily, giving the sky its eerie, fiery glow. It's even more dramatic at sunrise or sunset! The sun is low on the horizon, so the light has to pass through more of the Earth's atmosphere. When wildfire smoke is present, the filtering is even stronger, and you can get a deep red or even a blood-orange sky. It can also look apocalyptic, if the smoke is especially thick. The sun can appear dimmed or even blotted out, casting an eerie sepia or orange hue over everything. That is sometimes called a 'smoke eclipse." When wildfire smoke fills the sky, air quality drops. Try to stay indoors or wear a well-fitted and properly worn, respirator-type mask (such as a NIOSH-certified N95 or equivalent respirator) if you head outside. Also, use an air purifier to keep the air clean.
Yahoo
13-03-2025
- Science
- Yahoo
How To View Tonight's Total Lunar Eclipse
'When the moon hits your eye like a big pizza pie, that's amore,' sang Dean Martin in the iconic song 'That's Amore.' And on March 13 or very early on March 14 (depending on your time zone), there will be plenty of amore in the sky with a total lunar eclipse. The moon will pass into the earth's darkest shadow creating the appearance of a reddish hue. 'A total lunar eclipse is one of the solar system's best magic tricks, caused by orbital mechanics of the earth, sun and moon, along with the interaction of sunlight with the earth's atmosphere.' says Cindy Young, a research physical scientist at NASA Langley Research Center. 'No magic hats or white rabbits required.'Young goes on to explain that this illusion occurs when the earth moves in between the sun and moon, placing its shadow upon the moon. 'The shadow cast upon the moon has a ruddy color, making the moon appear as though it has turned red,' she says. Most people have the opportunity to see a total lunar eclipse in their lifetime. According to Kunio Sayanagi, planetary science team lead at NASA Langley Research Center, nine lunar eclipses are expected between 2025 and 2035. After this month's lunar eclipse, the next one will occur March 3, 2026 for the western part of the United States. And the eastern region will experience it on June 26, 2029. However, this particular upcoming lunar eclipse is special because it can be viewed throughout North America. "The March 14 eclipse is the only total lunar eclipse in the next ten years that is visible from the beginning to the end from the entire continental United States," says Sayanagi. 'The last time a total lunar eclipse was visible from the beginning to the end from the entire continental United States was in January 2019.' What is the best way to see and photograph the total lunar eclipse and when you can see it? NASA's Young and Sayanagi offer details on everything connected with the full lunar A total lunar eclipse occurs when the earth moves in between the sun and moon and casts its darkest inner shadow upon the moon. 'At this point, the only light illuminating the moon has traveled through the earth's atmosphere to reach it,' says Young. She also shares that the particles in the earth's atmosphere interact with the sunlight, effectively scattering light at shorter blue wavelengths, a process called Rayleigh Scattering. 'This phenomenon is also responsible for the blue sky and red sunsets,' she adds. 'The longer red wavelengths are left to be refracted through earth's atmosphere, causing the shadow cast upon the moon to have a ruddy color.' So this effect makes the moon look red. A solar eclipse occurs when the moon passes in between the earth and the sun. 'From the earth's perspective, the sun and the moon are a similar size in the sky, so it is possible for the moon to completely cover the disk of the sun, which happens during a total solar eclipse,' says Young. 'The shadow cast on the earth by the moon in this case is very narrow and one must be within a couple hundred kilometers to view totality. A partial solar eclipse can be observed outside of this very narrow band, but still within the moon's shadow.' Meanwhile, a total lunar eclipse isn't the multi-sensory experience of a total solar eclipse but it is still captivating and can be seen by more people. 'During a total lunar eclipse, the shadow of the earth is large enough to cover the entire moon such that anyone who can view the moon at night will see the lunar eclipse, so it is visible to a larger set of the population,' she A total lunar eclipse only occurs during a full moon. The eclipse begins on March 13 at 11:57 p.m. EDT (March 13 at 8:57 p.m. PDT). But it will be very gradual and not very noticeable at first. 'The moon will slowly enter earth's shadow and darken toward totality,' explains Sayanagi. 'After totality, the moon will gradually emerge from the earth's shadow and will look like a regular full moon by the end.' The last total lunar eclipse was November 8, 2022. According to Sayanagi, the total lunar eclipse can be viewed from anywhere within the United States. "You can see the eclipse from anywhere in North and South America," he explains. "Just look up from where you have an open view of the sky, and look for the moon.'Related: 'The best part of the eclipse is called 'totality' which lasts for about an hour starting on March 14 at 2:26 a.m. EDT (March 13 at 11:26 p.m. PDT), when the moon will shine in a deep red hue,' says Sayanagi. Unlike the solar eclipse where people need protection to view it, people can safely view the lunar eclipse with the naked eyes without protection. A cell phone is ideal. 'We live in an amazing time—20 years ago, we needed a high-end film camera with an expensive zoom lens and a beefy tripod to photograph a lunar eclipse,' says Sayanagi. 'Now, many modern cell phone cameras are good enough to take nice photos. How you photograph it is up to your artistic sense. Zoom in to capture details of the moon, or zoom out to include the foreground, etc. There are many ways to have lots of fun.' He also suggests adding effects by using a flashlight to illuminate the foreground. 'A lunar eclipse progresses very slowly, so you have a lot of time to experiment,' he explains. 'A lunar eclipse is different from a solar eclipse in this aspect because the totality lasts for only several minutes in a solar eclipse.'Also, a digital camera with an optical zoom of x30 or better will offer an almost-professional looking photograph. And if your camera is equipped with image stabilization, no tripod is needed. 'I recommend experimenting with the exposure settings to see how best to bring out more details,' Sayanagi says. 'Generally, digital cameras tend to overexpose the moon so underexposing with a shorter shutter speed, will help bring out more details.' Usually, total lunar eclipses happen twice a year. And they are visible from half of earth, whichever side happens to be facing the moon. The lunar eclipse in March 2025 happens just when the moon is over the Americas. Sayanagi predicts that the next total lunar eclipse of 2025 will be this September. 'But it will be visible only from longitudes between Australia and Africa, and not visible from the Americas,' he explains. 'The next total lunar eclipse that will be visible from the United States is March 3, 2026 for the western United States, or June 26, 2029 for the eastern United States. Up Next:Cindy Young, a research physical scientist at NASA Langley Research Center Kunio Sayanagi, planetary science team lead at NASA Langley Research Center
Yahoo
07-03-2025
- Science
- Yahoo
Total lunar eclipse to produce a blood moon this March. When to see it in Louisiana
On March 14, a total lunar eclipse will produce a blood moon, and the phenomena will be visible throughout the U.S. During this celestial event, the Earth's shadow will cover the moon, making it glow bright red. The eclipse will begin at 10:57 p.m. CDT, with totality occurring at 1:26 a.m. CDT and concluding at 2:31 a.m. CDT. A total lunar eclipse is a rare astronomical phenomenon that's referred to as a "blood moon." In Louisiana, if skies are clear and your view is unobstructed, this celestial event will be visible to the naked eye. However, for better observation, binoculars or telescopes can be used. During a total lunar eclipse, the moon is covered by the umbra, which is the darkest part of Earth's shadow, and sunlight is blocked. While totally covered by Earth's shadow, the moon will take on a red hue due to the interaction between the sun's light and Earth's atmosphere. Furthermore, during an event called Rayleigh Scattering, shorter blue-light wavelengths are scattered while longer red-and-orange-light wavelengths pass through the Earth's atmosphere and thus illuminate the moon. Presley Bo Tyler is a reporter for the Louisiana Deep South Connect Team for Gannett/USA Today. Find her on X @PresleyTyler02 and email at PTyler@ This article originally appeared on Shreveport Times: When is the total lunar eclipse and blood moon? When to see in Louisiana
