Tetons and Snake River, Planet Earth
1.08.2014

An alluring night skyscape, this scene looks west across the Grand Teton National Park, Wyoming, USA, Planet Earth. The Snake River glides through the foreground, while above the Tetons' rugged mountain peaks the starry sky is laced with exceptionally strong red and green airglow.

XMM Launched
21.12.1999

X-ray astronomy entered a golden age earlier this month with the successful launch of the X-ray Multi-Mirror (XMM) satellite. XMM's three huge telescope barrels each hold 58 concentric cylindrical mirrors, together totaling a surface area rivaling a tennis court.

APOD: 2024 June 23 Б The Colors of Saturn from Cassini
23.06.2024

What creates Saturn's colors? The featured picture of Saturn only slightly exaggerates what a human would see if hovering close to the giant ringed world. The image was taken in 2005 by the robot Cassini spacecraft that orbited Saturn from 2004 to 2017.

Webb Telescope Mirror Rises after Assembly
9.05.2016

Move over Hubble -- here comes the James Webb Space Telescope (JWST). JWST promises to be the new most powerful telescope in space. In the last month, the 18-segment gold-plated primary mirror for JWST was unveiled. In the featured time-lapse video taken last week, the 6.5-meter diameter mirror was raised to a vertical position.

The Colors of Saturn from Cassini
30.03.2020

What creates Saturn's colors? The featured picture of Saturn only slightly exaggerates what a human would see if hovering close to the giant ringed world. The image was taken in 2005 by the robot Cassini spacecraft that orbited Saturn from 2004 to 2017.

Simulation: Formation of the First Stars
30.06.2021

How did the first stars form? To help find out, the SPHINX computer simulation of star formation in the very early universe was created, some results of which are shown in the featured video. Time since the Big Bang is shown in millions of years on the upper left.

Sutter s Mill Meteorite
28.04.2012

Last Sunday's bright fireball meteor falling through skies over California and Nevada produced sonic booms over a broad area around 7:21 am. Estimates indicate the meteor was about the size of a minivan.

A Cloud Shadow Sunrise
27.02.2002

What could cause a ray of dark? Such a ray was caught in spectacular fashion above the Florida Everglades two years ago. The cause is something surprisingly familiar: a shadow. The gold-tinged cloud near the horizon blocks sunlight from reflecting off air behind the cloud, making that column of air appear unusually dark.

A Five Planet Dawn
30.01.2016

As January closes and in the coming days of February, early morning risers can spot the five naked-eye planets before dawn. Though some might claim to see six planets, in this seaside panoramic view all five celestial wanderers were found above the horizon along with a bright waning gibbous Moon on January 27.

Mars, Antares, Moon, and Saturn
4.10.2014

Mars, Antares, Moon, and Saturn are the brightest celestial beacons in this serene sky. The Sun's golden light is still scattered along the southwestern horizon though, captured after sunset on September 28.