Gamma Ray Moon
27.05.2006

If you could see gamma rays - photons with a million or more times the energy of visible light - the Moon would appear brighter than the Sun! The startling notion is demonstrated by this image...

M33: Triangulum Galaxy
20.12.2012

The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way.

Radio, The Big Ear, and the WOW Signal
2.05.2020

Since the early days of radio and television we have been freely broadcasting signals into space. For some time now, we have been listening too. A large radio telescope at Ohio State University known as affectionately The Big Ear was one of the first listeners.

APOD: 2023 October 11 Б NGC 1097: Spiral Galaxy with Supernova
11.10.2023

What's happening in the lower arm of this spiral galaxy? A supernova. Last month, supernova SN 2023rve was discovered with UAE's Al-Khatim Observatory and later found to be consistent with the death explosion of a massive star, possibly leaving behind a black hole.

Pleiades from Planet Earth
1.11.2025

The lovely Pleiades star cluster shines in Earth's night sky, a compact group of stars some 400 light-years distant toward the constellation Taurus and the Orion Arm of our Milky Way galaxy. Recognized since ancient times, the remarkable celestial gathering is visible to the unaided eye.

NGC 2403 in Camelopardalis
23.07.2011

Magnificent island universe NGC 2403 stands within the boundaries of the long-necked constellation Camelopardalis. Some 10 million light-years distant and about 50,000 light-years across, the spiral galaxy also seems to have more than its fair share of giant star forming HII regions, marked by the telltale reddish glow of atomic hydrogen gas.

Bright Planetary Nebula NGC 7027 from Hubble
9.01.2018

It is one of the brightest planetary nebulae on the sky -- what should it be named? First discovered in 1878, nebula NGC 7027 can be seen toward the constellation of the Swan (Cygnus) with a standard backyard telescope.

Beautiful Albireo AB
24.02.2022

Beta Cygni is a single bright star to the naked eye. About 420 light-years away it marks the foot of the Northern Cross, famous asterism in the constellation Cygnus. But a view through...

Fragments of Comet LINEAR
11.08.2000

What do you call a bunch of comet fragments anyway ... a flock, a covey, a swarm? The question is definitely relevant to comet LINEAR (C/1999 S4 LINEAR) whose nucleus apparently fragmented late last month during its first trip through the inner solar system.

How Big Is 2001 KX76
30.08.2001

Newly discovered minor planet 2001 KX76 is circled in the top panel above, a recent composite image from the European Southern Observatory's 2.2 meter telescope at La Silla, Chile. Though 2001 KX76 appears...