Tuesday, 7 February, 2012

Can there be a sun-snowshower? Photo: Zaphod These cumulus clouds are not sunshower material. See a late spring sun-snow shower here! Almost all of us have noticed a summer rainshower that occurs while the sun is shining on us. In this event, known as a sun-shower, the raindrops fall from a type of cloud called [...]

I saw a photo of the sun rising above Lake Michigan. Why does sun appear flat? ENLARGE Photo of moon partially obscured by earth’s atmosphere: NASA. The distortion of the moon’s lower section is caused by refraction. This flattening of the sun on the horizon is an example of a mirage. Mirages are not illusions; [...]

You’ve seen photos of lunar and solar eclipses, or maybe you’ve even been present for one yourself, but have you ever seen an eclipse of the Earth? Astronaut Bill McArthur and flight engineer Valery Tokarey snapped this photo from aboard the International Space Station on March 29, 2006 during a total eclipse of the sun. [...]

Yes, this is a real picture. More accurately, it’s 165 pictures pasted together from NASA’s Cassini spacecraft’s flyby of Saturn as the planet between the probe and the sun. From this unique vantage point, the contrast of light and shadow enabled astronomers to discern new bands of ice and dust — perhaps the remnants of [...]

Many of the colors we see in fall are always present, but normally they’re hidden from view, says UW-Madison Arboretum native plant gardener Susan Carpenter. The leaves of trees and other plants contain three main pigments: carotene, anthocyanin, and the photosynthetic pigment, chlorophyll, which captures the sun’s energy to make food for plants. As the [...]

“Technically, there is no surface of the Sun,” says UW-Madison’s Sanjay Limaye. The senior scientist and educator with the Space Science and Engineering Center explains that unlike the hard, physical boundary here on Earth, the Sun’s surface is a hot mass of gas that is more or less continuous with its atmosphere. “The Sun is [...]