Four Faces of Mars
5.07.1999

As Mars rotates, most of its surface becomes visible. During Earth's recent pass between Mars and the Sun, the Hubble Space Telescope was able to capture the most detailed time-lapse pictures ever from the Earth. Dark and light sand and gravel create an unusual blotted appearance for the red planet.

Unusual Plates on Mars
28.02.2005

What are those unusual plates on Mars? A leading current interpretation holds that they are blocks of ice floating on a recently frozen sea covered by dust. The unusual plates were photographed recently by the European Space Agency's Mars Express spacecraft currently orbiting Mars.

Planetary Nebula Mz3: The Ant Nebula
5.02.2001

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

Planetary Nebula Mz3: The Ant Nebula
1.05.2005

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

Planetary Nebula Mz3: The Ant Nebula
25.04.2010

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

Planetary Nebula Mz3: The Ant Nebula
25.04.2021

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

Planetary Nebula Mz3: The Ant Nebula
26.04.2015

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

Ancient Craters on Saturns Rhea
30.05.2006

Saturn's ragged moon Rhea has one of the oldest surfaces known. Estimated as changing little in the past billion years, Rhea shows craters so old they no longer appear round their edges have become compromised by more recent cratering.

APOD: 2025 July 13 Б Planetary Nebula Mz3: The Ant Nebula
13.07.2025

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

Juno Mission Trailer
28.06.2016

What will NASA's Juno spacecraft find when it reaches Jupiter next Monday? Very little, if Juno does not survive Jupiter Orbit Insertion, a complex series of operations in an unknown environment just above Jupiter's cloud tops.