APOD: 2023 December 5 Б Energetic Particle Strikes the Earth
5.12.2023

It was one of the most energetic particles ever known to strike the Earth -- but where did it come from? Dubbed Amaterasu after the Shinto sun goddess, this particle, as do all cosmic rays...

APOD: 2026 January 18 Б Jupiter from the Webb Space Telescope
18.01.2026

This infrared view of Jupiter by Webb is illuminating. High-resolution infrared images of Jupiter from the James Webb Space Telescope (Webb) reveal, for example, differences between high-floating bright clouds -- including the Great Red Spot -- and low-lying dark clouds.

APOD: 2026 August 4 Б Curious Cometary Knots in the Helix Nebula
4.08.2026

What causes unusual knots of gas and dust in planetary nebulas? Seen also in the Ring Nebula, the Dumbbell Nebula and NGC 2392, the knots' existence was not initially predicted, and their origins are still not well understood.

Comet Hale-Bopp Inbound
19.12.1996

Headed toward the inner Solar System, the much anticipated Comet Hale-Bopp has promised to put on a big show next spring. The comet's apparent brightness is currently approaching 4th magnitude and its inbound journey has been closely followed by many observers.

Doomed Star Eta Carinae
28.11.2004

Eta Carinae may be about to explode. But no one knows when - it may be next year, it may be one million years from now. Eta Carinae's mass - about 100 times greater than our Sun - makes it an excellent candidate for a full blown supernova.

G21.5-0.9: A Supernova s Cosmic Shell
21.04.2005

The picture is lovely, but this pretty cosmic shell was produced by almost unbelievable violence - created when a star with nearly 20 times the mass of the sun blasted away its outer layers in a spectacular supernova explosion.

A Meteor Shower Fireball Movie
12.08.2005

Go outside tonight and see a celestial light show -- the later the better. Tonight is the peak of the month-long Perseid Meteor Shower. Although visible every year at this time, the Perseids are expected to appear particularly active this year due to the relative absence of glare from the Moon during the peak.

Doomed Star Eta Carinae
26.03.2006

Eta Carinae may be about to explode. But no one knows when - it may be next year, it may be one million years from now. Eta Carinae's mass - about 100 times greater than our Sun - makes it an excellent candidate for a full blown supernova.

Astronomy From An F-18
28.01.2000

In an era of blossoming ground and space-based observatories, astronomers are also pushing the envelope with airborne instrumentation - successfully capturing an asteroid occultation from a high performance jet aircraft. This blinking animation represents...

The Lunar X
10.12.2016

The striking X appearing in this lunarscape is easily visible in binoculars or a small telescope. Yet, not too many have seen it. The catch is this lunar X is fleeting, only apparent in the hours before the Moon's first quarter phase.