Striped Sand Dunes on Mars
6.01.2021

Why are these sand dunes on Mars striped? No one is sure. The featured image shows striped dunes in Kunowsky Crater on Mars, photographed recently with the Mars Reconnaissance OrbiterБs HiRISE Camera. Many Martian dunes are known to be covered unevenly with carbon dioxide (dry ice) frost, creating patterns of light and dark areas.

Sun and Moon Halo
3.04.2015

Two pictures captured on April 1 are combined in this creative day and night composite. Separated in time by about 10 hours the images otherwise match, looking along the coast at Östersund Sweden.

Life Enabling Plumes above Enceladus
16.04.2017

Does Enceladus have underground oceans that could support life? The discovery of jets spewing water vapor and ice was detected by the Saturn-orbiting Cassini spacecraft in 2005. The origin of the water feeding the jets, however, was originally unknown.

The Shining Clouds of Mars
5.06.2021

The weathered and layered face of Mount Mercou looms in the foreground of this mosaic from the Curiosity Mars rover's Mast Camera. Made up of 21 individual images the scene was recorded just after sunset on March 19, the 3,063rd martian day of Curiosity's on going exploration of the Red Planet.

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.

Oceans Under Jupiters Callisto
31.07.2001

Why does Jupiter's moon Callisto alter the magnetic field of Jupiter in its vicinity? Callisto itself does not have a strong magnetic field. One possible answer is that Callisto harbors sub-surface oceans of electrically conducting salt-water. This hypothesis was bolstered recently by a new analysis of how Callisto creates and dissipates heat.

The Dotted Dunes of Mars
31.08.2004

What causes the black dots on dunes on Mars? As spring dawns on the Northern Hemisphere of Mars, dunes of sand near the poles being to defrost. Thinner regions of ice typically thaw first revealing sand whose darkness soaks in sunlight and accelerates the thaw.

Searching for Meteorites in Antarctica
26.12.2002

Where is the best place on Earth to find meteorites? Although meteors fall all over the world, they usually just sink to the bottom of an ocean, are buried by shifting terrain, or are easily confused with terrestrial rocks.

Odysseus Crater on Tethys
5.02.2017

Some moons wouldn't survive the collision. Tethys, one of Saturn's larger moons at about 1000 kilometers in diameter, survived the collision, but today exhibits the resulting expansive impact crater Odysseus. Sometimes called...

Ancient Cratered Plains on Ganymede
12.07.1996

The largest moon in the Solar System shows regions that are ancient and battered. The high density of craters demonstrate that patches of Ganymede are indeed billions of years old. This photo is one of a series released by NASA two days ago from the Galileo spacecraft orbiting Jupiter.