Our Busy Solar System
24.07.2002

Our Solar System is a busy place. Although the major planets get the most press, a swarm of rocks, comets, and asteroids also exist. The above plot shows the placement of known inner Solar System objects on 2002 July 20. The light blue lines indicate the orbits of planets.

Going Wild
19.03.2004

Dynamic jets of gas and dust surround one of the most active planetary surfaces in the solar system in this wild-looking picture of a comet nucleus. The comet's designation is 81P/Wild...

Halley Dust and Milky Way
9.05.2014

The early morning hours of May 6 were moonless when grains of cosmic dust streaked through dark skies. Swept up as planet Earth plows through dusty debris streams left behind periodic Comet Halley, the annual meteor shower is known as the Eta Aquarids.

Perseid Meteors over Mount Shasta
8.08.2016

Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaks later this week is known as the Perseids -- the meteors all appear to came from a radiant toward Perseus.

Rosetta Approaches Asteroid Lutitea
24.04.2012

What would it look like to approach an asteroid in a spaceship? In 2010, ESA's robotic Rosetta spacecraft zipped past the asteroid 21 Lutetia taking data and snapping images in an effort to better determine the history of the asteroid and the origin of its unusual colors.

The Perseus Cluster of Galaxies
5.04.1996

Here is one of the largest objects that anyone will ever see on the sky. Each of the fuzzy blobs in the above picture is a galaxy, together making up the Perseus Cluster, one of the closest clusters of galaxies.

Starry Night Scavenger Hunt
15.06.2010

Did you know that Van Gogh's painting Starry Night includes Comet Hale-Bopp? Hopefully not, because it doesn't. But the above image does. Although today's featured picture may appear at first glance...

Starry Night Scavenger Hunt
18.09.2016

Did you know that van Gogh's painting Starry Night includes Comet Hale-Bopp? Hopefully not, because it doesn't. But the featured image does. Although today's picture may appear at first glance...

APOD: 2025 August 10 Б Zodiacal Road
10.08.2025

What's that strange light down the road? Dust orbiting the Sun. At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently just after sunset -- or just before sunrise -- and is called zodiacal light.

Solar Sail
8.03.2003

Nearly 400 years ago astronomer Johannes Kepler observed comet tails blown by a solar breeze and suggested that vessels might likewise navigate through space using appropriately fashioned sails. It is now widely recognized that...