Sungrazer
25.02.1997

Arcing toward a fiery fate, this Sungrazer comet was recorded by the SOHO spacecraft's Large Angle Spectrometric COronagraph (LASCO) on Dec. 23rd, 1996. LASCO uses an occulting disk, partially visible at the lower...

Gamma Ray Earth
31.03.2005

The pixelated planet above is actually our own planet Earth seen in gamma rays - the most energetic form of light. In fact, the gamma rays used to construct this view pack over 35 million electron volts (MeV) compared to a mere two electron volts (eV) for a typical visible light photon.

Sungrazer
20.05.2000

Arcing toward a fiery fate, this Sungrazer comet was recorded by the SOHO spacecraft's Large Angle Spectrometric COronagraph (LASCO) on Dec. 23rd, 1996. LASCO uses an occulting disk, partially visible at the lower...

Magnetar In The Sky
21.01.2000

Indicated on this infrared image of the galactic center region is the position of SGR 1900+14 - the strongest known magnet in the galaxy. SGR 1900+14 is believed to be a city-sized, spinning, super-magnetic neutron star, or Magnetar. How strong is a Magnetar's magnetic field?

A Solar Eclipse from the Moon
7.04.2014

Has a solar eclipse ever been seen from the Moon? Yes, first in 1967 -- but it may happen again next week. The robotic Surveyor 3 mission took thousands of wide angle television images of the Earth in 1967, a few of which captured the Earth moving in front of the Sun.

Cosmic Collision Forges Galactic Ring
16.09.2018

How could a galaxy become shaped like a ring? The rim of the blue galaxy pictured on the right is an immense ring-like structure 150,000 light years in diameter composed of newly formed, extremely bright, massive stars.

APOD: 2025 June 21 Б Two Worlds, Two Analemmas
20.06.2025

Sure, that figure-8 shaped curve you get when you mark the position of the Sun in Earth's sky at the same time each day over one year is called an analemma.

Comet Halleys Nucleus: An Orbiting Iceberg
3.01.2010

What does a comet nucleus look like? Formed from the primordial stuff of the Solar System, comet nuclei were thought to resemble very dirty icebergs. But ground-based telescopes revealed only the surrounding cloud of gas and dust of active comets nearing the Sun, clearly resolving only the comet's coma, and the characteristic cometary tails.

Cosmic Rays from Galactic Centers
11.11.2007

Where do cosmic rays come from? A major step toward answering this century old question may have just come in from the Auger Observatory project, the world's premier cosmic ray observatory. That high energy fundamental particles are barreling through the universe has been known for about a century.

Symbiotic R Aquarii
28.06.2017

A long recognized naked-eye variable star, R Aquarii is actually an interacting binary star system, two stars that seem to have a close, symbiotic relationship. About 710 light years away, it consists of a cool red giant star and hot, dense white dwarf star in mutual orbit around their common center of mass.