Astronomy Picture Of the Day (APOD)The Most Distant Sun
When is the Sun most distant from Earth? It happened again just this past weekend. A common misconception is that the Sun is most distant during the winter, when it's the coldest. In truth, however, the seasonal temperatures are more greatly influenced by the number of daylight hours and how high the Sun rises.
How does a space shuttle that landed in California get back to Florida for its next launch? The answer is by ferry. NASA operates two commercial Boeing 747 airplanes modified to carry a space shuttle on their backs.
The Trifid Nebula, aka Messier 20, is easy to find with a small telescope, a well known stop in the nebula rich constellation Sagittarius. But where visible light pictures show the nebula divided into three parts by dark, obscuring dust lanes, this penetrating infrared image reveals filaments of glowing dust clouds and newborn stars.
Bright Galaxy NGC 2903
Spiral galaxy NGC 2903 is only some 20 million light-years distant in the constellation Leo. One of the brighter galaxies visible from the northern hemisphere, it is surprisingly missing from Charles Messier's famous catalog of celestial sights. This impressively sharp color image shows off the galaxy's beautiful blue spiral arms.
Night Shining Clouds
Alluring noctilucent or night-shining clouds lie near the edge of space, some 80 kilometers above Earth's surface. Of course, when viewed from space the clouds are more properly called polar mesospheric clouds (PMCs) -- seen here for the first time in image data from the Aeronomy of Ice in the Mesosphere (AIM) satellite.
Red, White, and Blue Sky
Contrasting colors in this beautiful sunset sky were captured on June 30 from Clear Creek Canyon Observatory in central Arizona, USA. The twilight scene includes brilliant Venus as the evening star, with a bright Saturn just above it, shining through thin clouds.
At the Edge of Victoria Crater
We're going in. The robotic Opportunity rover currently rolling across Mars has been prowling around the edge of the largest crater it has visited since landing over three years ago. It has been studying Victoria crater and looking for a way in.
Zooming in to the Pelican Nebula
Where on the sky is the Pelican Nebula? APOD features many objects on the night sky, but usually does not have the resources to show exactly where on the night sky each objects lies.
Steep Cliffs on Mars
Vertical cliffs of nearly two kilometers occur near the North Pole of Mars. Also visible in the above image of the Martian North Polar Cap are red areas of rock and sand, white areas of ice, and dark areas of unknown composition but hypothesized to be volcanic ash.
Jumbled Galaxy Centaurus A
At the center of this sharp skyscape, Centaurus A seems to be a fantastic jumble of old yellow stars, young blue star clusters, and imposing dark dust lanes. Spanning over 60,000 light-years, the peculiar elliptical galaxy is apparently the result of a collision of two otherwise normal galaxies.