Thinning Martian Atmosphere

NASA's Curiosity rover has found evidence of the heavier argon isotope Ar³⁸ in greater concentrations in the Martian atmosphere relative to the lighter Ar³⁶, supporting the theory that Mars' gravity is insufficient to prevent as much as 95% of its original atmosphere from escaping into space.

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.

Plate Tectonics on Mars

Previously thought to exist nowhere else in the solar system but Earth, scientists have discovered evidence of plate tectonics on Mars in about a dozen satellite images of surface fault systems collected from orbiting spacecraft.

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.

Mars Experiences "Marsquakes"

Researchers using High Resolution Imaging Science Experiment (HiRISE) imagery of the surface of Mars have examined a fault system known as Cerberus Fossae and determined that Mars experiences "marsquakes," its equivalent of earthquakes, suggesting possible volcanism still at work below the surface.

Salt Water Grooves on Mars

Images from the Mars Reconnaissance Orbiter have revealed narrow grooves that periodically appear on slopes in the warmer regions of Mars that suggest salty water may still flow at rare times on the surface.

New Model for Mars' Size

A new mathematical model and simulation of the formation of our solar system explains why Mars has only one tenth the mass of Earth or Venus, with Jupiter migrating to within 1.5 AU of the Sun while accumulating mass, robbing Mars of much of the raw material for planet formation.

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.

Massive Blast Created Phobos

Astronomers have uncovered firm evidence, namely the presence of minerals that only form in liquid water, that Mars' largest moon Phobos owes its origin to a massive collision of an object with the planet's surface.

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.

Wet, Non-Acidic Mars

Lengthy analysis of data collected by the Martian rover Spirit in 2005 has revealed a previously wet and non-acidic environment on Mars, possibly hinting at an ancient environment favorable for life.

Mars Loses Atmosphere

Astrophysicists have discovered that Mars constantly loses a portion of its atmosphere to the pressure of the solar wind, especially to energetic solar events known as corotating interacting regions (CIR), due to its lack of the protective effects of a planetary magnetic field.

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.

Ancient Ocean on Mars

A new NASA map adds further evidence that an ancient ocean once covered up to one third of Mars' surface, with extensive valley networks that imply heavy rainfall that would feed such a large body of water.

Evidence of Ancient Lake on Mars

The first conclusive geological evidence has been found of the existence of an ancient lake of water on the surface of Mars more than 3 billion years ago.

Methane Belch on Mars Hints at Possible Life

Using Earth-based telescopes, researchers at NASA's Goddard Space Flight Center have confirmed that in the late summer of 2003, almost 21,000 tons of methane gas was released from localized areas on the western hemisphere of Mars.

A finding of extraterrestrial methane is significant because the gas is associated with life here on Earth, either as byproducts of digestion or decaying biomatter. As a waste product of life processes, it may also serve as a food source for other forms of life. With past studies finding no regular methane content in the Martian atmosphere, the sudden presence and quick dispersion of the gas could indicate an organic origin.

Similar methane appearances are found in some parts of Earth's oceans as decaying life on the sea floor releases a "belch" of gas. Other sources of methane are the presence of microbial life, possibly living in or beneath the Martian soil. Methane-producing microbes have been found in extreme Earth environments such as Arctic soil and volcanic vents.

Nonorganic sources of methane are also possible, involving volcanic processes or the mixture of water, carbon dioxide and other chemicals. Trapped underground, these gasses could be released through surface fissures as the pressure increases.

These results were published online in the January 15th edition of Science.

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