APOD: 2026 July 29 Б Psyche Receives Gravity Assist from Mars
29.07.2026

Solar System bodies make deep space exploration more fuel efficient! TodayБs video shows the Psyche spacecraft gaining speed and changing its trajectory with minimal fuel spent due to a gravity assist from Mars in May 2026. Mars has an average orbital speed of almost 87,000 km/h (54,000 mph) around the Sun.

APOD: 2026 May 6 Б The Retrograde Dance of Saturn and Neptune
6.05.2026

What does it mean for Saturn and Neptune to be in retrograde? Featured is a composite of images taken over 34 nights from May 2025 to February 2026 tracing Saturn (brighter, foreground) and Neptune (dimmer, background). Over that time, the two planets exhibited retrograde motion, meaning they appeared to move backward in the sky.

The Long Jet of the Lighthouse Nebula
21.02.2014

The Lighthouse nebula was formed by the wind of a pulsar, a rapidly rotating, magnetized neutron star, as it speeds through the interstellar medium at over 1,000 kilometers per second. Some...

Pacman and Hartley
7.10.2010

Touring the solar system with a 6 year orbital period, small comet Hartley 2 (103/P Hartley) will make its closest approach to planet Earth on October 20 and its closest approach to the Sun on October 28. It may become a naked-eye comet, just visible in clear, dark skies.

Opportunity s Mars Analemma
16.05.2014

Staring up into the martian sky, the Opportunity rover captured an image at 11:02 AM local mean time nearly every 3rd sol, or martian day, for 1 martian year. Of course, the result...

APOD: 2025 November 11 Б Jupiter in Ultraviolet from Hubble
11.11.2025

Jupiter looks a bit different in ultraviolet light. To better interpret Jupiter's cloud motions and to help NASA's robotic Juno spacecraft understand the planetary context of the small fields that it sees, the Hubble Space Telescope was being directed to regularly image the entire Jovian giant.

A Twisted Meteor Trail Over Tenerife
2.06.2010

Did this meteor take a twisting path? No one is sure. Considered opinions are solicited. Meteors, usually sand sized grains that originate in comets, will typically disintegrate as they enter the Earth's atmosphere. A fast moving meteor ionizes molecules in the Earth's atmosphere that subsequently glow when they reacquire electrons.

Lewins Challenge: 360 Degree Star Trails
17.07.2011

You could be the first person ever to take a real single-exposure image like this. The above image from Vienna, Austria is not real in the sense that the 360 degree star trails in the sky appear only because of a digital trick.

Solstice at Newgrange
20.12.2008

Tomorrow's solstice marks the southernmost point of the Sun's annual motion through planet Earth's sky and the astronomical beginning of winter in the north. In celebration of the northern winter solstice...

Star Trails in Northern Skies
12.09.1998

As the Earth spins on its axis, the sky seems to rotate around us. This motion produces the beautiful concentric trails traced by the stars in this time exposure of the night sky.