Lunar Plain Not Impact Crater

The latest analysis of the Oceanus Procellarum, the large, dark plain on the near side of the Moon, shows it is rimmed by structures that form straight lines and angles, implying formation due to tectonic activity and not as the result of an impact.

Ancient Streambed on Mars

NASA's Curiosity Rover has discovered rounded pebbles and gravel on  Mars, evidence of an ancient stream with free-flowing water that once existed on the surface of the planet.

New Mineral from Meteorite

Scientists studying the Allende meteorite that landed in Mexico in 1969 have discovered a new mineral embedded in the rock, a titanium oxide dubbed panguite, a mineral previously unknown to science and believed to be one of the oldest minerals formed in the solar system.

Nanoparticles in Moon Dust

Researchers using a synchrotron-based nano tomograph have discovered glassy nanoparticles -- some no larger than individual molecules -- mixed in with lunar soil samples that explain many strange properties observed in lunar soil contrary to conventional soil behavior.

Signs of Volcanoes on Mars

High-resolution images of a group of valleys near the Martian equator named the Athabasca Valles show more than 250 coiling spiral patterns that resemble the lava flows on the Big Island of Hawaii, suggesting once-active volcanoes on Mars.

New Class of Landform on Mars

Images from the Mars Reconnaissance Orbiter have revealed a new class of geologic landform named periodic bedrock ridges on the surface of Mars, a structure similar to sand dunes but formed by the wind erosion of bedrock material.

Younger Moon

A new analysis of a Moon rock brought back by Apollo 16 astronauts in 1972 reveals the Moon's age to be 200 million years younger than previously calculated, suggesting the oldest crust on both Earth and Moon formed at about the same time.

Moon Bulge Explained

The lunar far-side highlands, an area of elevated topography located on the far side of the Moon, has been explained using a mathematical model as the result of tidal forces early in its formation acting on a solid outer crust floating on an internal layer of magma.

Evidence of Martian Water

By analyzing the very soil it became stuck in 2009, the NASA's Mars Expedition Rover Spirit has found further evidence of water in recent geologic history as stratified layers close to the surface formed from seepage of surface frost or snow.

"Walnut" Moon Mystery

New planetary models have shed light on the origin of the unusual "walnut" ridge formation of Saturn's moon Iapetus, with the moon in a region far enough from the planet to retain much of its initial rotational spin while still forming and producing the characteristic bulge along its equator.

Moon's Geologic Complexity

Data returned from NASA's Lunar Reconnaissance Orbiter (LRO) shows a level of previously unseen compositional differences in the lunar crust from high-resolution infrared maps, revealing a more complex geological makeup than ever believed.

Mixed, Varied Asteroids

A survey of near-Earth objects by NASA's Spitzer Space Telescope reveals a wide and mixed array of compositions with much greater diversity than expected, indicating that these asteroids may have a variety of origins.

Ancient Ocean on Mars

A new study analyzing water-related topography concludes that a vast sustained sea covered roughly a third of the surface of Mars about 3.5 billion years ago.

Unusual Martian Rock

A strange surface rock examined by NASA's Mars rover Opportunity is believed to have formed deep within the crust, possibly ejected from a nearby crater upon impact, and may reveal information about the composition of the planet's interior.