From the Museum to Mars: a meteorite returns home
A piece of Martian meteorite is being returned to the red planet by NASA.
The meteorite was found in Oman in 1999 and was registered into the Museum's collection in 2000. It is now under the care of Dr Caroline Smith, Principal Curator of Meteorites.
This fragment is called Sayh al Uhaymir 008, or SaU 008. It will be launched into space on board NASA's Mars 2020 rover mission.
The rock will have taken a million years to arrive on Earth from Mars, and now it is being prepared by scientists for a much shorter journey home.
Mars 2020's goal is ambitious: collect samples from the planet's surface that a future mission could potentially return to Earth. It's part of NASA's long-term programme of robotic exploration on Mars.
The mission will look for signs that parts of Mars are habitable in addition to evidence of past microbial life. A drill will collect samples from the most promising rocks and soils and set them aside, in the hopes that future missions could collect them and return them to Earth.
One of the rover's tools will be a high-precision laser called SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals), designed to examine rock features as fine as a human hair.
Why this fragment?
SaU 008 will help to get the design of SHERLOC absolutely right. Scientists want the laser to be so precise that they will carry out target practice to tweak its settings.
They decided to use a real Martian meteorite to calibrate the laser, which is being built at NASA's Jet Propulsion Laboratory in Pasadena in California.
Dr Luther Beegle, who works at the lab, said, 'We're studying things on such a fine scale that slight misalignments, caused by changes in temperature or even the rover settling into sand, can require us to correct our aim.
'By studying how the instrument sees a fixed target, we can understand how it will see a piece of the Martian surface.'
SaU 008 was chosen for the job because of its good condition. Scientists need a meteorite to be solid enough that it would not flake apart during the intense launch and landing. It also needed to have certain chemical features to test the laser's sensitivity.
Experts at NASA asked Dr Smith for help in finding the perfect candidate because of the strength of the Museum's collections. They looked at several samples, ultimately settling on SaU 008. The rest of the meteorite will remain at the Museum.
Caroline said, 'Every year, we provide hundreds of meteorite specimens to scientists all over the world for study.
'This is a first for us: sending one of our samples back home for the benefit of science.
'I'm so excited to be working with colleagues at NASA on missions that will help our understanding of Mars and the rest of the solar system. That aim also fits in with the Museum's scientific research, as we are using Martian meteorites to study the surface of the planet.'
SaU008 will be the first Martian meteorite to have a fragment return to the planet's surface, though not the first on a return trip to Mars.
NASA's Mars Global Surveyor included a chunk of a meteorite known as Zagami. It's still floating around the red planet on board the now-defunct orbiter.
Future missions - and spacesuits
The next NASA mission to Mars is planned to launch in summer 2020, when Earth and Mars are in good positions relative to each other, meaning it will take less power for the spacecraft carrying the rover to travel between the planets.
As well as taking samples, the mission will gather knowledge about the possibilities of future human expeditions to Mars.
Opportunities include testing a method for producing oxygen from the Martian atmosphere, identifying other resources and improving landing techniques. Scientists will also characterise weather, dust and other potential environmental conditions that could affect future work on Mars.
SHERLOC will also test materials that could support a human mission to Mars, including spacesuit fabric for future missions. NASA will be able to see how these materials hold up under Martian weather, including radiation.
'The SHERLOC instrument is a valuable opportunity to prepare for human spaceflight as well as to perform fundamental scientific investigations of the Martian surface,' said Marc Fries, a SHERLOC co-investigator and curator of extraterrestrial materials at Johnson Space Center.
'It gives us a convenient way to test material that will keep future astronauts safe when they get to Mars.'
See the meteorite
A section of this meteorite is on display in the Museum's From the Beginning gallery.