Astronomy Picture Of the Day (APOD)Copper Moon, Golden Gate
When the Moon rose over San Francisco's Golden Gate Bridge on May 15, both bridge and Moon were in already in Earth's shadow. Of course, the bridge is in the Earth's shadow nightly, while the Moon only has that opportunity twice a year, during a lunar eclipse.
A Primodrial Quasar
What did the first quasars look like? The nearest quasars are now known to be supermassive black holes in the centers of galaxies. Gas and dust that falls toward a quasar glows brightly, sometimes outglowing the entire home galaxy.
The Andromeda Deep Field
What can you learn from looking into the depths of space? In an effort to find out true ages of stars in neighboring Andromeda galaxy's halo, astronomers stared into the galaxy giant with the new Advanced Camera for Surveys through the Hubble Space Telescope.
The Holographic Principle
Is this image worth a thousand words? According to the Holographic Principle, the most information you can get from this image is about 3 x 1065 bits for a normal sized computer monitor.
Dark Sky, Bright Sun
In low Earth orbit there is not enough atmosphere to diffuse and scatter sunlight, so shadows are black and the sky is dark - even when the Sun shines. The harsh lighting produced this dramatic...
A Tale of Two Nebulae
This colorful telescopic view towards the northern constellation Lyra reveals dim outer regions around M57, popularly known as the Ring Nebula. While modern astronomers still refer to M57 as a planetary nebula, at one light-year across M57 is not a planet but the gaseous shroud of a dying sun-like star.
Moon Slide Slim
No special filters - or even a telescope - are required to enjoy a leisurely lunar eclipse. In fact, watched from all over the night side of planet Earth, these regular celestial performances have entertained many casual skygazers. Still, this eye-catching picture of a lunar eclipse may look unfamiliar.
The North Pole of Venus
If you could look down on the North Pole of Venus what would you see? The Magellan probe that orbited Venus from 1990 to 1994 was able to peer through the thick Venusian clouds and build up the above image by emitting and re-detecting cloud-penetrating radar.
Mercury Transits the Sun
How big is the Sun? The Sun is not only larger than any planet, it is larger than all of the planets put together. The Sun accounts for about 99.9 percent of all the mass in its Solar System.
In the Vicinity of the Cone Nebula
Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars.