Crossing The Ring Plane
1.08.1995

"I do not know what to say in a case so surprising, so unlooked for and so novel." announced Galileo when Saturn's rings appeared to vanish in 1612. In fact, every 15 years Saturn's rings seem to almost disappear as viewed from the Earth.

Three CubeSats Released
6.01.2014

Cubes are orbiting the Earth. Measuring ten-centimeters on a side, CubeSats -- each roughly the size of a large coffee mug -- are designed to be inexpensive both to build and to launch. Pictured above, three CubeSats were released from the International Space Station (ISS) last November by the arm of the Japanese Kibo Laboratory module.

Sunrise at the South Pole
5.10.2021

Sunrise at the South Pole is different. Usually a welcome sight, it follows months of darkness -- and begins months of sunshine. At Earth's poles, it can take weeks for the Sun to rise, in contrast with just minutes at any mid-latitude location.

The Kepler 90 Planetary System
28.04.2020

Do other stars have planetary systems like our own? Yes -- one such system is Kepler-90. Cataloged by the Kepler satellite that operated from Earth orbit between 2009 and 2018, eight planets were discovered, giving Kepler-90 the same number of known planets as our Solar System.

Leonids from Leo
16.11.2003

Is Leo leaking? Leo, the famous sky constellation visible on the left of the above all-sky photograph, appears to be the source of all the meteors seen in 1998's Leonids Meteor Shower. That...

Planet Earth at Night II
17.06.2023

Recorded during 2017, timelapse sequences from the International Space Station are compiled in this serene video of planet Earth at Night. Fans of low Earth orbit can start by enjoying the view as green and red aurora borealis slather up the sky.

The Moon During a Total Lunar Eclipse
25.05.2021

How does the Moon's appearance change during a total lunar eclipse? The featured time-lapse video was digitally processed to keep the Moon bright and centered during the 5-hour eclipse of 2018 January 31. At first the full moon is visible because only a full moon can undergo a lunar eclipse.

Fire on Earth
21.11.2000

Sometimes, regions of planet Earth can be seen lit up with fire. Since fire is the rapid acquisition of oxygen, and since oxygen is a key indicator of life, fire on any planet would be an indicator of life on that planet.

Earth's Temperature
30.01.1997

What's the temperature outside? No matter where you are on Earth, the above map can tell you. This global montage was created using the temperature data from numerous satellites orbiting the Earth. This...

APOD: 2023 December 17 Б Geminids over Chinas Nianhu Lake
17.12.2023

Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Gemini. That is why the major meteor shower in December is known as the Geminids -- because shower meteors all appear to come from a radiant toward Gemini.