Why Stars Twinkle
25.07.2000

This is what a star really looks like from the surface of the Earth. To the best the human eye can see, stars are so far away they appear the same as would infinitesimal points of light.

Supernova Remnant In M82
16.12.1999

This false-color radio wavelength picture of an expanding stellar debris cloud is the product of one of the largest radio astronomy experiments ever. Combining the output of 20 radio telescopes scattered around planet Earth...

A Young Supernova in the Nearby Pinwheel Galaxy
26.08.2011

A nearby star has exploded and telescopes all over the world are turning to monitor it. The supernova, dubbed PTF 11kly, was discovered by computer only two days ago as part of the Palomar Transit Factory (PTF) sky survey utilizing the wide angle 1.2-meter Samuel Oschwin Telescope in California.

21st Century M101
13.07.2012

One of the last entries in Charles Messier's famous catalog, big, beautiful spiral galaxy M101 is definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way Galaxy.

M44: A Beehive of Stars
3.08.1998

M44 is a prominent open cluster of stars. Nicknamed Praesepe and "The Beehive", it is one of the few open clusters visible to the unaided eye. M44 was thought to be a nebula until Galileo used an early telescope to resolve the cluster's bright blue stars. These stars are visible in the above image.

Pluto: The Frozen Planet
28.12.1997

The Hubble Space Telescope imaged Pluto and its moon Charon in 1994. Pluto is usually the most distant planet from the Sun but because of its elliptic orbit Pluto crossed inside of Neptune's orbit in 1979 and will cross back out again in 1999.

Nearby Spiral Galaxy NGC 4945
12.04.1999

For such a close galaxy, NGC 4945 is easy to miss. NGC 4945 is a spiral galaxy in the Centaurus Group of galaxies, located only six times farther away than the prominent Andromeda Galaxy. The thin disk galaxy is oriented nearly edge-on, however, and shrouded in dark dust.

APOD: 2023 February 1 Б The Seventh World of Trappist 1
1.02.2023

Seven worlds orbit the ultracool dwarf star TRAPPIST-1. A mere 40 light-years away, many of the exoplanets were discovered in 2016 using the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) located in the Atlas Mountains of Morocco, and later confirmed with telescope including NASA's Spitzer Space Telescope.

Saturn in Color
12.03.1997

Saturn is unusual but photogenic. The second largest planet in our Solar System, behind Jupiter, has been easily identifiable at night since history has been recorded. It was only with the invention of the telescope, however, that any evidence of its majestic ring system became apparent.

Comet Impacts on Jupiter
14.07.1995

In July of 1994, pieces of Comet Shoemaker-Levy 9, also known as the "string of pearls" comet, collided with the planet Jupiter. As the comet fragments smashed in to Jupiter, the resulting explosions scattered large quantities of dusty cometary debris into the Jovian atmosphere.