Katie Joy, McMurdo station, 8th December 2012

Today the ANSMET team had a full science briefing for our future mission collecting meteorites on the boundary between the Transantarctic Mountains and the south polar plateau (see photo 1). Ralph Harvey has provided a previous post (see below) about the ice regions that will be visited by the ANSMET systematic team (Mt. Bumstead, Larkman Nunatak, and the Grosvenor Mts.) and reconnaissance team (Graves Nunatak and Amundsen Glacier) over the next six weeks – there is a lot to do and lots of interesting places to visit.

the science meeting

Both new team members and veterans alike were also educated about the procedures for how the team operates in the field hunting for meteorites, and the important process of careful collection of the samples we hope to find.

We also learnt about how to recognise meteorites on the ice and distinguishing them from local terrestrial rock which will likely be found in many of our search areas, including in glacial moraines (large areas of rock that accumulate at the edges of glaciers and flowing ice). Many of us on the team work with meteorite samples in the laboratory, however, often we tend to work with small chips (~1 cm or less in size) of much larger rocks, or petrographic thin sections (very thin rock slices mounted on glass slides) taken from the interior part of the meteorite. Therefore, we need to train our eyes to recognise that meteorites can look slightly different on the outside as the colour, texture, and coverage of their surficial fusion crust varies from stone to stone. (n.b. Fusion crust is a thin exterior melted portion of the stone which forms when the meteorite passes through the Earth’s atmosphere). Different meteorite types, and where they have come from, will be discussed in future blog posts as there is a lot here to discuss, but we hope to find samples that originated from Mars, the Moon and many different types of asteroids.

I recall from taking part in ANSMET last year that you learn quickly how to spot meteorites, and that there are lots of experienced people on hand to discuss and advise about the recognition process. So we are looking forward to putting our knowledge into practice when we hopefully deploy to the field next week and collect lots of good meteorites this 2012-2013 season. In the mean time, we will be enjoying spending time in McMurdo station, visiting the neighbours (see photo 2), and meeting the McMurdo staff who have been working hard to get everything ready for us to go into the field.  

McMurdo’s neighbors

There is lots of great information about the meteorite collection process on this website, so surf on over to the links, FAQ and download pages.  Links include the partners in the program (NASA’s Johnson Space Center and the Smithsonian Institution).  The FAQs provide more details about ANSMET itself, and the downloads are more detailed stuff you can take home and read at your leisure.