The Mars Virtual Microscope



There has never been a space mission to Mars that has successfully returned samples back to Earth...... and yet here is a set of samples that almost certainly came from the red planet. They are a group of achondritic meteorites (the SNC meteorites) named after the initials of the locations where the first three were found: Shergotty, India (found in 1865); Nakhla, Egypt (found in 1912) and Chassigny, France (found in 1815). The SNC subgroups are the shergottites, chassignites and nakhlites. These are all now thought to have originated on Mars. In 1996 a further rock type was added to the suite - orthopyroxenite.

Most meteorites that have found their way to Earth appear to have come from the asteroid belt between Mars and Jupiter and like the planets these asteroids formed around 4.5 billion years ago. Because of their small size they quickly lost their original supply of internal heat and have remained solid, virtually since the birth of the solar system. The SNC meteorites are different as they crystallized from molten rock betwen 150 million and 1.35 billion years ago. The only place molten rock has occurred in such relatively recent times is inside planets. Mars and Venus are the obvious candidates as they are nearest to Earth, and of these Mars is the more likely source because of its lower gravity and thinner atmosphere (making it easier to eject material from the planets surface into space).

Corroborating evidence to support a Martian origin came when gases were measured in glass within a SNC meteorite (EETA 79001 - a 7.9kg specimen found in Antarctica’s Elephant Moraine in 1980). The composition of this gas exactly matched measurements of the martian atmosphere made by NASA’s Viking lander spacecraft.

Unlike other virtual microscopes on this site, the Mars virtual microscope contains images collected using the electron microprobe at the Open University. In due course the Mars virtual microscope may turn into a virtual microprobe.

SNC classification
See also
Mars RoversMars-3.html
What Mars can tell us
Beagle 2
List of Martian meteorites
Mars Science Laboratory
View Mars Rocks
basaltic shergottite Shergotty
basaltic shergottite RBT 04261
basaltic shergottite NWA 2975
lherzolitic shergottite ALHA 77005
lherzolitic shergottite LEW 88516
olivine-phyric shergottite LAR 06319
olivine-phyric shergottite EETA 79001
clinopyroxenite Nakhla 
clinopyroxenite Y000593
clinopyroxenite Lafayette
clinopyroxenite MIL 03346
dunite Chassigny
dunite NWA 2737
ALH 84001Mars-Shergotty-1.htmlMars-RBT-04261.htmlMars-NWA-2975_2.htmlMars-ALHA-77005.htmlMars-LEW-88516-1.htmlMars-LAR-06319.htmlMars-EETA79001.htmlRockMonth-2011-08-a.htmlMars-Y000593.htmlMars-Lafayette.htmlMars-MIL03346.htmlMars-Chassigny-1.htmlMars-NW2737.htmlMars-ALH84001-1.htmlshapeimage_11_link_0shapeimage_11_link_1shapeimage_11_link_2shapeimage_11_link_3shapeimage_11_link_4shapeimage_11_link_5shapeimage_11_link_6shapeimage_11_link_7shapeimage_11_link_8shapeimage_11_link_9shapeimage_11_link_10shapeimage_11_link_11shapeimage_11_link_12shapeimage_11_link_13