Astronomy Picture Of the Day (APOD)A Perseid Meteor
Tonight the Perseid Meteor Shower reaches its maximum. Grains of rocky ice will streak across the sky as they evaporate during entry into Earth's atmosphere. These ice chips were shed from Comet Swift-Tuttle. The Perseids result from the annual crossing of the Earth through Comet Swift-Tuttle's orbit.
Nebulosity in Sagittarius
What causes the colors in this beautiful nebulosity in Sagittarius? Dubbed NGC 6589 and NGC 6590, the colors of this nebulosity, are caused by gas and dust. The blue color of the nebula nearest the bright stars is caused by reflection off interstellar dust.
The Hydra Cluster of Galaxies
You are flying through space and come to ... the Hydra Cluster of Galaxies. Listed as Abell 1060, the Hydra Cluster contains well over 100 bright galaxies. Clusters of galaxies are the largest gravitationally-bound objects in the universe.
White Oval Clouds on Jupiter
What are those white ovals all over Jupiter? Storms! Jupiter's clouds can swirl rapidly in raised high-pressure storm systems that circle the planet. The above pictured white ovals are located near the Great Red Spot, and have persisted on Jupiter since the 1930s. The Great Red Spot has persisted for at least 300 years.
Jupiter's Ring Halo
Why do small particles hover around Jupiter's rings? These particles form a previously unknown ring halo, recently discovered by the robot spacecraft Galileo currently orbiting Jupiter. Galileo obtained this image when on the far side of Jupiter - from this orientation scattered sunlight makes the halo ring visible.
Hale-Bopp from Indian Cove
Good cameras were able to obtain impressive photographs of Comet Hale-Bopp when at its brightest earlier this year. In the above photograph taken April 5th, Comet Hale-Bopp was imaged from the Indian Cove Campground in the Joshua Tree National Forest in California, USA.
M101: The Pinwheel Galaxy
Why do many galaxies appear as spirals? A striking example is M101, shown above, whose relatively close distance of about 22 million light years allow it to be studied in some detail. Recent evidence...
A Rusty Sunset on Mars
On Mars, sunsets can appear salmon pink. The unusual color is partly due to rust: oxidized iron from Martian dust circulating in the Martian atmosphere. Clouds appear in the morning and evening, but usually evaporate in the midday Sun.
The Cygnus Loop
15,000 years ago a star in the constellation of Cygnus exploded -- the shockwave from this supernova explosion is still expanding into interstellar space! The collision of this fast moving wall of gas with...
The Cat's Eye Nebula
Three thousand light years away, a dying star throws off shells of glowing gas. This image from the Hubble Space Telescope reveals "The Cat's Eye Nebula" to be one of the most complex planetary nebulae known.