Triton: Neptune's Largest Moon
10.10.1999

One hundred and fifty three years ago, on October 10th, 1846, William Lassell was observing the newly discovered planet Neptune. He was attempting to confirm his observation, made just the previous week, that Neptune had a ring. But this time he discovered that Neptune had a satellite as well.

The Medulla Nebula Supernova Remnant
17.01.2021

What powers this unusual nebula? CTB-1 is the expanding gas shell that was left when a massive star toward the constellation of Cassiopeia exploded about 10,000 years ago. The star likely detonated when it ran out of elements, near its core, that could create stabilizing pressure with nuclear fusion.

Pluto: New Horizons
18.10.2001

Pluto's horizon spans the foreground in this artist's vision, gazing sunward across that distant and still unexplored world. Titled New Horizons, the painting also depicts Pluto's companion, Charon, as a darkened, ghostly apparition with a luminous crescent against a starry background.

APOD: 2024 April 1 Б Swirling Magnetic Field around Our Galaxys Central Black Hole
31.03.2024

What's happening to the big black hole in the center of our galaxy? It is sucking in matter from a swirling disk -- a disk that is magnetized, it has now been confirmed. Specifically, the black hole's accretion disk has recently been seen to emit polarized light, radiation frequently associated with a magnetized source.

The Light of Stars
8.05.2012

What's moving? Time lapse videos of the sky can be quite spectacular when they last long enough for stars, planets, aurora, and clouds to appear to move in just a few seconds. Pictured...

Apollo 11: Onto a New World
19.05.1998

A human first set foot on another world on July 20, 1969. This world was Earth's own Moon. Pictured above is Neil Armstrong preparing to take the historic first step. On the way down the Lunar Module ladder, Armstrong released equipment which included the television camera that recorded this fuzzy image.

Dark Volcano Active on Io
9.11.1997

The surface of Io is changing even as we watch. The inset frame of Jupiter's most active moon was taken by the robot spacecraft Galileo in April. Just last month the larger image was taken. The new large black spot reveals that a volcano named Pillan Patera has been erupting during the interim.

Europa's Surface
13.08.1996

Voyager spacecraft images of Europa's surface, like the one above, are suggestive of sea ice on Earth. The criss-crossing dark streaks may indeed be cracks in its ice-covered surface caused by Jupiter's tidal stresses accompanied by the freezing and expansion of an underlying layer of water.

Comet PanSTARRS, Moon, and Venus
22.07.2015

It is the object to the left of the big tree that's generating much recent excitement. If you look closely, there you can see Comet PanSTARRS, complete with two tails. During July, this comet has increased markedly in brightness and has just passed its closest approach to Earth.

Apollo 11: Onto a New World
20.07.2009

A human first set foot on another world on July 20, 1969. This world was Earth's own Moon. In honor of today's 40th anniversary, NASA has released a digitally restored video of this milestone in human history. Pictured above is Neil Armstrong preparing to take the historic first step.