Expanding Plume from DARTs Impact
5.10.2022

What happens if you crash a spaceship into an asteroid? In the case of NASA's DART spaceship and the small asteroid Dimorphos, as happened last week, you get quite a plume. The goal...

Comet Halleys Nucleus: An Orbiting Iceberg
4.01.2010

What does a comet nucleus look like? Formed from the primordial stuff of the Solar System, comet nuclei were thought to resemble very dirty icebergs. But ground-based telescopes revealed only the surrounding cloud of gas and dust of active comets nearing the Sun, clearly resolving only the comet's coma, and the characteristic cometary tails.

A Blazing Fireball between the Orion Nebula and Rigel
16.11.2015

What's happening to that meteor? A few days ago, a bright fireball was photographed from the Alps mountain range in Switzerland as it blazed across the sky. The fireball, likely from the Taurids...

Humanity Explores the Solar System
30.04.2013

What spacecraft is humanity currently using to explore our Solar System? Presently, every inner planet has at least one robotic explorer, while several others are monitoring our Sun, some are mapping Earth's Moon, a few are chasing asteroids and comets, one is orbiting Saturn, and several are even heading out into deep space.

W5: Pillars of Star Formation
15.12.2014

How do stars form? Images of the star forming region W5 like those in the infrared by NASA's Wide Field Infrared Survey Explorer (WISE) satellite provide clear clues with indications that massive stars near the center of empty cavities are older than stars near the edges.

An Atlas V Rocket Launches OSIRIS REx
17.10.2016

Have you ever seen a rocket launched into the Solar System? Last month a large Atlas V rocket blasted off from Launch Complex 41 in Florida carrying the ORISIX-REx spacecraft. This robotic spacecraft will attempt to land on Asteroid Bennu and return some of its soil to Earth.

An Annular Solar Eclipse over New Mexico
25.12.2019

What is this person doing? In 2012 an annular eclipse of the Sun was visible over a narrow path that crossed the northern Pacific Ocean and several western US states. In an annular solar...

Space Station Lookout
10.04.2013

If you glanced out a side window of the International Space Station, what might you see? If you were Expedition 34 flight engineer Chris Hadfield, and you were looking out one of windows of Japan's Kibo Research Module on February 26, you might have seen the above vista.

How Much is That Comet in the Window?
27.03.1996

The above true-color photo taken March 25th shows Comet Hyakutake passing below the stars of the Big Dipper. Many astronomy enthusiasts delight in helping people in their local community see the comet. Both Jerry Bonnell and I (RJN) from APOD have been so inclined - both now and when Comet Halley came by in 1986.

Aurora over Icelandic Fault
30.08.2016

Admire the beauty but fear the beast. The beauty is the aurora overhead, here taking the form of great green spiral, seen between picturesque clouds with the bright Moon to the side and stars in the background. The beast is the wave of charged particles that creates the aurora but might, one day, impair civilization.