European Association for Astronomy Education

Source: Mars Reconnaissance Orbiter

Area of about 460 meters across, in which carbonate minerals
have been identified from spectrometer observations.
Image credit: NASA/JPL-Caltech/Univ. of Arizona

Rocks on Mars dug from far underground by crater-blasting impacts are providing glimpses of one possible way Mars' atmosphere has become much less dense than it used to be.

At several places where cratering has exposed material from depths of about 5 kilometers (3 miles) or more beneath the surface, observations by a mineral-mapping instrument on NASA's Mars Reconnaissance Orbiter indicate carbonate minerals.

These are not the first detections of carbonates on Mars. However, compared to earlier findings, they bear closer resemblance to what some scientists have theorized for decades about the whereabouts of Mars' "missing" carbon. If deeply buried carbonate layers are found to be widespread, they would help answer questions about the disappearance of most of ancient Mars' atmosphere, which is deduced to have been thick and mostly carbon dioxide. The carbon that goes into formation of carbonate minerals can come from atmospheric carbon dioxide. (read more)

Source: Chandra

Image credit:
X-ray: NASA/CXC/CfA/J.Wang et al.;
Optical: Isaac Newton Group of Telescopes, La Palma/Jacobus Kapteyn Telescope,
Radio: NSF/NRAO/VLA

Chandra has released another marvellous picture. This composite image shows the central region of the spiral galaxy NGC 4151, dubbed the "Eye of Sauron" by astronomers for its similarity to the eye of the malevolent character in "The Lord of the Rings". (read more)

Source: NASA News

NASA will host a media teleconference to discuss the first spacecraft to orbit Mercury.

NASA's MErcury Surface, Space ENvironment, GEochemistry, and Ranging, or MESSENGER, will enter orbit at approximately 9 p.m. EDT on Thursday, March 17. The spacecraft has conducted more than a dozen laps through the inner solar system for nearly 7 years.

Media teleconference participants are:
-- Andy Calloway, MESSENGER mission operations manager, Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md.
-- Carl Engelbrecht, MESSENGER propulsion subsystem lead, APL
-- Sean Solomon, MESSENGER principal investigator, Carnegie Institution of Washington