LDN 1622: Dark Nebula in Orion
21.02.2020

The silhouette of an intriguing dark nebula inhabits this cosmic scene. Lynds' Dark Nebula (LDN) 1622 appears against a faint background of glowing hydrogen gas only visible in long telescopic exposures of the region. In contrast, the brighter reflection nebula vdB 62 is more easily seen, just above and right of center.

When Roses Aren t Red
9.02.2024

Not all roses are red of course, but they can still be very pretty. Likewise, the beautiful Rosette Nebula and other star forming regions are often shown in astronomical images with a predominately red hue, in part because the dominant emission in the nebula is from hydrogen atoms.

Castle and Meteor by Moonlight
13.08.2011

Each August, as planet Earth swings through dust trailing along the orbit of periodic comet Swift-Tuttle, skygazers enjoy the Perseid Meteor Shower. As Earth moves through the denser part of the comet's wide...

Falcon 9 and Milky Way
14.05.2016

On May 6, the after midnight launch of a SpaceX Falcon 9 rocket lit up dark skies over Merritt Island, planet Earth. Its second stage bound for Earth orbit, the rocket's arc seems to be on course for the center of the Milky Way in this pleasing composite image looking toward the southeast.

1901 Photograph: The Orion Nebula
17.08.2019

By the turn of the 20th century advances in photography contributed an important tool for astronomers. Improving photographic materials, long exposures, and new telescope designs produced astronomical images with details not visible at the telescopic eyepiece alone.

Edwin Hubble Discovers the Universe
26.04.2020

How big is our universe? This very question, among others, was debated by two leading astronomers 100 years ago today in what has become known as astronomy's Great Debate. Many astronomers then believed that our Milky Way Galaxy was the entire universe. Many others, though, believed that our galaxy was just one of many.

APOD: 2023 December 20 Б Ice Halos over Bavaria
20.12.2023

What's causing those unusual sky arcs? Ice crystals. While crossing a field of fresh snow near Fцssen, Bavaria, Germany, earlier this month, the photographer noticed that he had entered an ice fog.

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.

Mercury Spotting
8.05.2003

Can you spot the planet? The diminutive disk of Mercury, the solar system's innermost planet, spent about five hours crossing in front of the enormous solar disk yesterday (Wednesday, May 7th), as viewed from the general vicinity of planet Earth.

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.