Iridium 52: Not A Meteor
22.10.1999

While hunting for meteors in the night sky above the White Mountains near Bishop, California, astrophotographer James Young instead captured this brilliant celestial apparition. Recorded near twilight on August 13, the bright streak is not the flash of a meteor trail but sunlight glinting from a satellite.

The First Explorer
12.08.2006

Inaugurating the era of space exploration for the US, the First Explorer, a thirty pound satellite, was launched into Earth orbit on February 1, 1958 by the Army Ballistic Missle Agency. Explorer I carried instruments to measure temperatures, micrometeorite impacts, and an experiment designed by James A.

Aurora and Orion
25.01.1997

Looking toward the south from low Earth orbit, the crew of the Space Shuttle Endeavor made this stunning time exposure of the Aurora Australis or southern lights in April of 1994. Aurora are visible at high northern latitudes as well, with the northern lights known as Aurora Borealis.

APOD: 2025 February 17 Б SpaceX Rocket Launch Plume over California
16.02.2025

What's happened to the sky? Last Monday, the photogenic launch plume from a SpaceX rocket launch created quite a spectacle over parts of southern California and Arizona. Looking at times like a giant...

A Near Record Ozone Hole in 2003
6.10.2003

As expected, the ozone hole near Earth's South Pole is back again this year. This year's hole, being slightly larger than North America, is larger than last year but short of the record set on 2000 September 10. Ozone is important because it shields us from damaging ultraviolet sunlight.

Collinder 399: The Coat Hanger
11.01.2007

Is this coat hanger a star cluster or an asterism? This cosmic hang-up has been debated over much of last century, as astronomers wondered whether this binocular-visible object is really a physically associated open cluster or a chance projection. Chance star projections are known as asterisms, an example of which is the popular Big Dipper.

3D Mercury Transit
24.11.2006

Mercury is now visible shortly before dawn, the brightest "star" just above the eastern horizon. But almost two weeks ago Mercury actually crossed the face of the Sun for the second time in the 21st century.

Phobos: Moon over Mars
21.03.2024

A tiny moon with a scary name, Phobos emerges from behind the Red Planet in this timelapse sequence from the Earth-orbiting Hubble Space Telescope. Over 22 minutes the 13 separate exposures were captured near the 2016 closest approach of Mars to planet Earth. Martians have to look to the west to watch Phobos rise, though.

Falcon 9 Launches to Orbit
8.06.2010

A new rocket, the Falcon 9, was launched successfully from Cape Canaveral, Florida, USA, last week. The Falcon 9, standing about as high as a 15-floor building, was developed by the commercial SpaceX corporation as a step toward a relatively inexpensive space launch system.

Phobos: Moon over Mars
20.07.2017

A tiny moon with a scary name, Phobos emerges from behind the Red Planet in this timelapse sequence from the Earth-orbiting Hubble Space Telescope. Over 22 minutes the 13 separate exposures were captured near the 2016 closest approach of Mars to planet Earth. Martians have to look to the west to watch Phobos rise, though.