A Dangerous Sunrise on Gliese 876d
21.05.2008

On planet Gliese 876d, sunrises might be dangerous. Although nobody really knows what conditions are like on this close-in planet orbiting variable red dwarf star Gliese 876, the above artistic illustration gives one impression.

Phaethon s Brood
23.12.2017

Based on its well-measured orbit, 3200 Phaethon (sounds like FAY-eh-thon) is recognized as the source of the meteroid stream responsible for the annual Geminid meteor shower. Even though most meteor showers' parents are comets, 3200 Phaethon is a known and closely tracked near-Earth asteroid with a 1.4 year orbital period.

Solar System Portrait
14.02.2013

On another Valentine's Day (February 14, 1990), cruising four billion miles from the Sun, the Voyager 1 spacecraft looked back to make this first ever family portrait of our Solar System. The complete portrait is a 60 frame mosaic made from a vantage point 32 degrees above the ecliptic plane.

Comet Encke s Tail Ripped off
3.10.2007

Swinging inside the orbit of Mercury, on April 20th periodic comet Encke encountered a blast from the Sun in the form of a Coronal Mass Ejection (CME). When CMEs, enormous clouds of energetic particles ejected from the Sun, slam into Earth's magnetosphere, they often trigger auroral displays.

Happy 40th Birthday NASA
1.10.1998

Happy Birthday, NASA! The National Aeronautics and Space Administration officially began operations on October 1, 1958, absorbing its forerunner organization the National Advisory Committee for Aeronautics, NACA. Its landmark achievements in human spaceflight include...

International Space Station in Transit
9.05.2003

A stunning telescopic image of the International Space Station crossing in front of an eight day old Moon, this picture was captured on April 11th. But while Wednesday's leisurely transit of Mercury across the Sun entertained observers all over the dayside of planet Earth, the audience for this lunar transit was more restricted.

Atmospheric Ring of Venus
8.06.2020

Why is Venus surrounded by a bright ring? Sometimes called a ring of fire, this rare ring is caused by the Sun's light being visible all around an object. Usually seen around...

APOD: 2026 April 18 Б PanSTARRS and Planets
18.04.2026

Near the eastern horizon before sunrise, Comet C/2025 R3 PanSTARRS is getting brighter. Readily visible in binoculars and small telescopes, the comet may be just on the verge of naked-eye visibility from dark sky sites.

The Rotating Jets of Comet Hyakutake
14.04.1996

Comet Hyakutake will reach its closest point to the Sun on May 1, passing well inside the orbit of Mercury. At this time, the comet's dust and ion tail will be at their greatest physical length.

Comet Encke Returns
23.12.2003

It's back. Every 3.3 years, Comet Encke swoops back into our inner Solar System. First officially discovered in 1786, Comet Encke is on its 59 th documented return, making it one of the best-studied comets on the sky.