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.

Super Earths May Circle Other Stars
20.03.2006

Are "super-Earths" common around other star systems? Quite possibly. Unexpected evidence for this came to light recently when a planet orbiting a distant star gravitationally magnified the light of an even more distant star.

Starlink over Orion
1.06.2021

What are those streaks across Orion? Most are reflections of sunlight from numerous Earth-orbiting Starlink satellites. Appearing by eye as a series of successive points floating across a twilight sky, the increasing number of SpaceX Starlink communication satellites are causing concern among many astronomers.

Von Braun's Wheel
28.03.1998

Orbiting 1,075 miles above the Earth, a 250 foot wide, inflated, reinforced nylon "wheel" was conceived in the early 1950s to function as a navigational aid, meteorological station, military platform, and way station for space exploration by rocket pioneer Wernher von Braun.

APOD: 2024 May 13 Б AR 3664 on a Setting Sun
13.05.2024

It was larger than the Earth. It was so big you could actually see it on the Sun's surface without magnification. It contained powerful and tangled magnetic fields as well as numerous dark sunspots.

Two Comets in Southern Skies
8.10.2022

Heading for its closest approach to the Sun or perihelion on December 20, comet C/2017 K2 (PanSTARRS) remains a sight for telescopic observers as it sweeps through planet Earth's southern hemisphere skies. First...

Von Braun's Wheel
2.03.1996

Orbiting 1,075 miles above the Earth, a 250 foot wide, inflated, reinforced nylon "wheel" was conceived in the early 1950s to function as a navigational aid, meteorological station, military platform, and way station for space exploration by rocket pioneer Wernher von Braun.

Mercury: A Cratered Inferno
19.08.2001

Mercury's surface looks similar to our Moon's. Each is heavily cratered and made of rock. Mercury's diameter is about 4800 km, while the Moon's is slightly less at about 3500 km (compared with about 12,700 km for the Earth). But Mercury is unique in many ways.

Mercury: A Cratered Inferno
12.09.1996

Mercury's surface looks similar to our Moon's. Each is heavily cratered and made of rock. Mercury's diameter is about 4800 km, while the Moon's is slightly less at about 3500 km (compared with about 12,700 km for the Earth). But Mercury is unique in many ways.

Eclipse over Chongqing, China
24.07.2009

The daytime sky grew dark, the temperature dropped, and lights came on as Chongqing, China, was plunged into the Moon's shadow during the July 22nd total solar eclipse. This serene, wide-angle view of the event looks to the east over the large, populous city from a newly constructed park.