At the Shadow s Edge
25.11.2021

Shaped like a cone tapering into space, the Earth's dark central shadow or umbra has a circular cross-section. It's wider than the Moon at the distance of the Moon's orbit though. But during the lunar eclipse of November 18/19, part of the Moon remained just outside the umbral shadow.

APOD: 2023 December 12 Б Aurora and Milky Way over Norway
12.12.2023

What are these two giant arches across the sky? Perhaps the more familiar one, on the left, is the central band of our Milky Way Galaxy. This grand disk of stars and nebulas here appears to encircle much of the southern sky.

APOD: 2024 August 14 Б Meteors and Aurora over Germany
14.08.2024

This was an unusual night. For one thing, the night sky of August 11 and 12, earlier this week, occurred near the peak of the annual Perseid Meteor Shower. Therefore, meteors streaked across the dark night as small bits cast off from Comet Swift-Tuttle came crashing into the Earth's atmosphere.

In the Center of the Omega Nebula
8.02.2004

In the depths of the dark clouds of dust and molecular gas known as the Omega Nebula, stars continue to form. The above image from the Hubble Space Telescope's Advanced Camera for Surveys shows exquisite detail in the famous star-forming region.

Gemini North Telescope Inaugurated
29.06.1999

A new mammoth telescope has begun to inspect the northern sky. The 8-meter Gemini North telescope, pictured above, was dedicated last week in Hawaii, with images documenting its unprecedented abilities being released. Within two years, sister telescope Gemini South will begin similar observations of the southern sky from Chile.

An Unusual Venusian Oval
13.02.2012

Why would Venus appear oval? Venus has been seen countless times from the surface of the Earth, and every time the Earth's atmosphere has dispersed its light to some degree. When...

A Laser Strike at the Galactic Center
1.12.2013

Why are these people shooting a powerful laser into the center of our Galaxy? Fortunately, this is not meant to be the first step in a Galactic war. Rather, astronomers at the Very Large Telescope (VLT) site in Chile are trying to measure the distortions of Earth's ever changing atmosphere.

Sprite Lightning in Slow Motion
13.10.2014

What causes sprite lightning? Mysterious bursts of light in the sky that momentarily resemble gigantic jellyfish have been recorded for over 25 years, but their root cause remains unknown. Some thunderstorms have them -- most don't. Recently, however, high speed videos are better detailing how sprites actually develop.

A Mercury Transit Music Video from SDO
11.05.2016

What's that small black dot moving across the Sun? Mercury. Possibly the clearest view of Mercury crossing in front of the Sun earlier this week was from Earth orbit. The Solar Dynamics Observatory obtained an uninterrupted vista recording it not only in optical light but also in bands of ultraviolet light.

Window Seat over Hudson Bay
22.09.2018

On the August 18 night flight from San Francisco to Zurich, a window seat offered this tantalizing view when curtains of light draped a colorful glow across the sky over Hudson Bay. Constructed...