Who knows what evil lurks in the hearts of galaxies? The Hubble knows. This Hubble Space Telescope picture of the center of the nearby elliptical galaxy NGC 4261 tells one dramatic tale. The gas and dust in this disk are swirling into what is ...
This sequence of false color X-ray images captures a rare event - the passage or transit of planet Mercury in front of the Sun. Mercury's small disk is silhouetted against the bright background of X-rays from the hot Solar Corona. It appears just ...
Using graphics and data from NASA's Compton Gamma Ray Observatory, this animation illustrates one of the most exciting mysteries of modern astrophysics, gamma-ray bursts. Incredibly gamma-ray bursts, sudden flashes of radiation with over 100,000 ...
cal galaxies are known for their old, red stars. But is this old elliptical up to new tricks? In recent years, the centers of elliptical galaxies have been found to emit unexpectedly high amounts of blue and ultraviolet light. Most blue light ...
A night sky can glow in fascinating ways. Through a clearing in the woods, the pictured sky above Alaska shines by reflected light from a nearby city, by the brightness of the Moon, and by aurora. The night sky in or near a city appears to ...
Not all evolving stars eject gas clouds that look like people. OH231.8+4.2 was a star much like our Sun that ran out of nuclear fuel to fuse in its core. It has therefore entered the planetary nebula phase, where it throws off its outer ...
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. In fact, the features seen in the ...
This sharp color image featuring Mars rock Yogi and the rolling Sojourner robot shows off Yogi's two-toned surface. Yogi appears to be leaning into the prevailing winds causing some to suggest that its color contrast may be caused by the ...
In the nineteenth century, dropping a time ball from a prominent location was a practical way of communicating the time to the surrounding country side and ships at sea. Initiating a fledgling time service for the United States, the U.S. Naval ...