Planetary Science

NASA's Mars rover Curiosity has placed its drill onto a series of four locations on a Martian rock and pressed down on it with the rover's arm, in preparation for using the drill in coming days.

The rover carried out this "pre-load" testing on Mars yesterday (Jan. 27). The tests enable engineers to check whether the amount of force applied to the hardware matches predictions for what would result from the commanded motions.

ESA's Venus Express has made unique observations of Venus during a period of reduced solar wind pressure, discovering that the planet's ionosphere balloons out like a comet's tail on its nightside.

The ionosphere is a region of weakly electrically charged gas high above the main body of a planet's atmosphere. Its shape and density are partly controlled by the internal magnetic field of the planet.

Fossilized hydrology A 3-D image of an impact crater in the Nilosyrtis area on the Martian surface shows long pipe-like ridges, fossilized evidence of ancient subsurface water flow. Credit: NASA Mars Reconnaissance Orbiter

PROVIDENCE, R.I. [Brown University] -- Networks of narrow ridges found in impact craters on Mars appear to be the fossilized remnants of underground cracks through which water once flowed, according to a new analysis by researchers from Brown University.

The HiRISE camera on the Mars Reconnaissance Orbiter snapped this series of pictures of sand dunes in the north polar region of Mars. The progression of false color pictures begins in early spring (panel a) when the ground is covered by a seasonal layer of carbon dioxide ice (dry ice) about 2 feet thick. As spring progresses the ice cracks (panel b), releasing dark sand from the dune below. When pressurized gas trapped below the ice layer is released it carries along sand and dust to the top of the ice layer where it is dropped in fan-shaped deposits downhill and downwind (panels c and d). The final panel shows more and more of the dark dunes as the overlying layer of seasonal ice evaporates back into the atmosphere.  Image credit:  NASA/JPL-Caltech/Univ. of Arizona

This movie shows two coronal mass ejections (CMEs) erupting from the sun on Jan. 23, 2013. The first was not directed at Earth; the second one is, but is not expected to have a strong impact. The movie was captured by the joint ESA/NASA mission the Solar and Heliospheric Observatory (SOHO), beginning at 7 p.m. EST on Jan. 22 and ending at 5:30 p.m. Jan. 23. Credit: ESA, NASA/SOHO/Goddard Space Flight Center > Download video (19 MB mov)