NICER at Night
1.06.2019

A payload on board the International Space Station, the Neutron star Interior Composition Explorer (NICER) twists and turns to track cosmic sources of X-rays as the station orbits planet Earth every 93 minutes. During orbit nighttime, its X-ray detectors remain on.

NGC 3521: Galaxy in a Bubble
2.04.2021

Gorgeous spiral galaxy NGC 3521 is a mere 35 million light-years away, toward the constellation Leo. Relatively bright in planet Earth's sky, NGC 3521 is easily visible in small telescopes but often overlooked by amateur imagers in favor of other Leo spiral galaxies, like M66 and M65.

Virgo Cluster Galaxies
17.04.2025

Galaxies of the Virgo Cluster are scattered across this nearly 4 degree wide telescopic field of view. About 50 million light-years distant, the Virgo Cluster is the closest large galaxy cluster to our own local galaxy group.

APOD: 2025 June 28 Б Lunar Farside
28.06.2025

Tidally locked in synchronous rotation, the Moon always presents its familiar nearside to denizens of planet Earth. From lunar orbit, the Moon's farside can become familiar, though. In fact this sharp picture, a mosaic from the Lunar Reconnaissance Orbiter's wide angle camera, is centered on the lunar farside.

Approaching the International Space Station
18.09.2000

Last Monday the crew of Space Shuttle Atlantis took in this view as they approached the developing International Space Station (ISS). From top to bottom, the astronauts saw a station currently consisting of the Progress supply module, the Zvezda service module, the Zarya cargo module, and the Unity connecting module.

Partial Eclipse, Cloudy Day
21.12.2001

Welcome to the December Solstice, first day of winter in the north and summer in the southern hemisphere of planet Earth. Today the Sun reaches its southernmost declination in the sky at 19:21 Universal Time.

Apollo 14 Deploys ALSEP
10.12.1995

After the lunar module of Apollo 14 set down on the Moon, Astronauts Alan Shepard and Edgar Mitchell deployed the Apollo Lunar Surface Experiments Package (ALSEP) and collected samples of lunar material. The ALSEP scientific experiments included a seismometer sensitive to slight lunar surface movements, and charged particle detectors which measured the solar wind.

D rad Bacteria: Candidate Astronauts
30.09.2002

These bacteria could survive on another planet. In an Earth lab, Deinococcus radiodurans (D. rad) survive extreme levels of radiation, extreme temperatures, dehydration, and exposure to genotoxic chemicals. Amazingly, they even have the ability to repair their own DNA, usually with 48 hours. Known as an extremophile, bacteria such as D.

Unusual Gullies and Channels on Mars
5.02.2003

What could have formed these unusual channels? Inside Newton Basin on Mars, numerous narrow channels run from the top down to the floor. The above picture covers a region spanning about 1500 meters across.

A Martian Day's End
6.07.1997

A Day or "Sol" on Mars is only 40 minutes longer than an Earth day - and Pathfinder's first day on Mars, Sol 1 according to its local calendar, was an eventful one. Still...