Mars in a Manger
30.04.2010

At opposition in late January, Mars shone very brightly in planet Earth's night sky, among the stars of the constellation Cancer the Crab. Since then the Red Planet has been fading, but still lingers in Cancer during April and May.

Discovery in Twilight
10.03.2011

As evening twilight faded on March 7, sky gazers around planet Earth enjoyed a beautiful pairing of young crescent Moon and brilliant planet Jupiter. Along with stars setting in the west, the two bright...

At the Limit of Diffraction
7.05.2015

Did you ever want to just look through the eyepiece of a large telescope in space? If you could, you would see a sharp view that was diffraction limited. Unaffected by atmospheric blurring that...

Animation: Perseid Meteor Shower
8.08.2018

Where do Perseid meteors come from? Mostly small bits of stony grit, Perseid meteoroids were once expelled from Comet Swift-Tuttle and continue to follow this comet's orbit as they slowly disperse. The featured animation depicts the entire meteoroid stream as it orbits our Sun.

New Horizons at Ultima Thule
29.12.2018

When we celebrate the start of 2019, on January 1 the New Horizons spacecraft will flyby Ultima Thule. A world of the Kuiper belt 6.5 billion kilometers from the Sun, the nickname Ultima Thule (catalog designation 2014 MU69) fittingly means "beyond the known world".

Geminids and the Mittens
25.12.2022

Asteroid 3200 Phaethon's annual gift to planet Earth always arrives in December. Otherwise known as the Geminid meteor shower, the source of the meteroid stream is dust shed along the orbit of the mysterious asteroid.

APOD: 2025 July 30 Б Coronal Loops on the Sun
30.07.2025

Our Sun frequently erupts in loops. Hot solar plasma jumps off the Sun's surface into prominences, with the most common type of prominence being a simple loop. The loop shape originates from the Sun's magnetic field, which is traced by spiraling electrons and protons.

Highlights of the Summer Sky
27.06.2018

What can you see in the night sky this summer? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early (northern) summer sky events fan out toward the left, while late summer events are projected toward the right.

Eclipsed Moon in Infrared
15.09.2001

The total lunar eclipse of September 1996 disappointed many observers in North America who were cursed with cloudy skies. However, the Midcourse Space Experiment (MSX) satellite had a spectacular view from Earth orbit and SPIRIT III, an onboard infrared telescope, was used to repeatedly image the moon during the eclipse.

Saturn At Night
4.03.2000

From a spectacular vantage point over 1.4 billion kilometers from the sun, the Voyager 1 spacecraft looked back toward the inner solar system to record this startling view of Saturn's nightside. The picture was taken on November 16, 1980, some four days after the robot spacecraft's closest approach to the gorgeous gas giant.