Eclipsed Moonlight
21.06.2011

A celestial prelude to today's solstice, the June 15 total lunar eclipse was one of the longest in recent years. It was also one of the darkest, but not completely dark. Even during...

Looking Sideways from the Parker Solar Probe
9.12.2019

Everybody sees the Sun. Nobody's been there. Starting in 2018 though, NASA launched the robotic Parker Solar Probe (PSP) to investigate regions near to the Sun for the first time. The PSP's looping orbit brings it yet closer to the Sun each time around -- every few months.

Space Laser Creates Artificial Star
25.04.2001

Some astronomers don't like stars. Bright star fluctuations can indicate how the Earth's atmosphere is changing, but many times no bright star exists in the direction where atmospheric information is needed.

APOD: 2025 February 10 Б Auroral Hummingbird over Norway
10.02.2025

Is this the largest hummingbird ever? Although it may look like a popular fluttering nectarivore, what is pictured is actually a beautifully detailed and colorful aurora, complete with rays reminiscent of feathers. This aurora...

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 Colorful Quadrantid Meteor
2.02.2021

Meteors can be colorful. While the human eye usually cannot discern many colors, cameras often can. Pictured is a Quadrantids meteor captured by camera over Missouri, USA, early this month that was not only impressively bright, but colorful. The radiant grit, likely cast off by asteroid 2003 EH1, blazed a path across Earth's atmosphere.

A Rainbow Geminid Meteor
19.12.2018

Meteors can be colorful. While the human eye usually cannot discern many colors, cameras often can. Pictured is a Geminid captured by camera during last week's meteor shower that was not only impressively bright, but colorful.

The Moons Of Earth
13.08.1998

While orbiting the planet during their June 1998 mission, the crew of the Space Shuttle Discovery photographed this view of two moons of Earth. Thick storm clouds are visible in the lovely blue planet...

APOD: 2025 March 4 Б A Quadruple Alignment over Italy
4.03.2025

Why does this Moon look so unusual? A key reason is its vivid red color. The color is caused by the deflection of blue light by Earth's atmosphere -- the same reason that the daytime sky appears blue. The Moon also appears unusually distorted.

A Telescope Laser Creates an Artificial Star
7.02.2005

What do you get when you combine one of the world's most powerful telescopes with a powerful laser? An artificial star. Monitoring fluctuations in brightness of a genuine bright star can indicate how the Earth's atmosphere is changing, but many times no bright star exists in the direction where atmospheric information is needed.