Herd hopes to uncover what the Tagish Lake meteorite could tell us about the early solar system and meteorite formation. Tiny grains in the rock, from stars that were present during our solar system’s creation, could reveal new information about the dust and gases that came together to make the planets, including one of Earth’s closest neighbours, Mars. Our whole understanding of how the solar system came to be could be revolutionized by what’s found in the meteorite.
Because it crashed on the frozen lake surface and was collected without being touched by human hands, the Tagish Lake meteorite represents the most pristine sample of minerals from outer space. This uncontaminated space sample allows Herd to perfect his space geology skills and establish himself as a leader in contamination prevention. “Chris is spearheading that effort in Canada,” says Lindsay Keller, a NASA scientist who also works with Tagish Lake meteorite samples at the Lyndon B. Johnson Space Center, near Houston, Texas. It is this kind of recognition of Herd’s work that could put Canada on deck for a mission to Mars.
Although the Tagish Lake meteorite is not from Mars, the type of contamination-free handling it requires is likely to be needed for Mars samples. Herd hopes to build a Canadian space geology program that NASA would look to as a key centre for sample analysis and as a place to help train astronaut-geologists. “Looking ahead 15 years or more, I want to have a chance to train astronauts to do geology on the surface of the moon and maybe even Mars,” he says. “I’d love to be there when they bring the first samples back from Mars.”
No one can predict when or if such a mission will take place, but Herd still dreams about how it could unfold. “I would design a human geological mission, modelled after the Apollo 17 moon mission. It had the only geologist-astronaut to walk on the moon—Harrison Schmitt. There was a support team back on Earth that included scientists with different expertise,” he says.
The scientific potential for a Mars geological mission is so great, Herd finds it almost impossible to decide what should be explored first. “The astronauts could do a series of geologic expeditions—from the lava flows on the flanks of Olympus Mons, to the flat-lying layers in Valles Marineris, to impact craters that might have once held standing water, to volcanoes that have erupted under the polar ice sheets.”
No matter what a mission to Mars might explore, because of the efforts of talented scientists like Herd and his colleagues, Canada could help demystify the red planet.
Chris Herd’s study of the Tagish Lake meteorite shows that Canada not only has the capabilities to handle valuable space samples, but can also ensure contamination-free preservation. “No other meteorite has ever been collected in this manner, and I suppose that arguably makes it the most important rock that’s ever been found anywhere on the Earth,” Herd affirms.
Using the U of A’s 29-piece collection of the fragmented meteorite, Herd looks for minerals or molecules that are not usually preserved when collected at above-freezing temperatures and contaminated by human contact. The Tagish Lake meteorite contains primitive molecules that are the building blocks of the components necessary for life. The distinctive rock also provides researchers with the opportunity to look for extraterrestrial ice.
Herd and his team made sure that Canada played a role in investigating the meteorite. “I thought this would be a great meteorite to have because of its scientific value. It also fell in Canadian territory. It really needed to be in a Canadian institution in order to maximize the science and to demonstrate that we could do great science on this,” he says.
Herd’s efforts to keep Canada at the forefront of space geology could mean participation by Canadian scientists on a Mars mission support team. “Chris is definitely one of the field’s rising stars. We tried to recruit him. He is the kind of scientist who has vision,” asserts NASA scientist Lindsay Keller.
“Having centres of excellence, like what Chris is doing in Canada, adds so much to our potential for unlocking the secrets of these samples,” Keller continues. Herd’s work could ultimately lead to great space initiatives for Canada, including collaborative efforts with NASA to better understand our solar system.
The Tagish Lake meteorite was acquired by the University of Alberta and the Royal Ontario Museum through a partnership between the university, the museum, the Department of Canadian Heritage, Natural Resources Canada, and the Canadian Space Agency.
The 29-piece collection is carefully stored in subzero conditions in the university’s meteorite collection and has likely never experienced temperatures much above freezing. The meteorite was formed in the extreme cold of space and was heated only on its outermost surface. Contrary to popular belief, meteorites are cold, not hot, when they land.
Herd also collaborates with NASA’s Johnson Space Center. Recently, one of Herd’s post-doctoral students spent time at NASA as part of Herd’s efforts to build bridges with other scientific communities and expose younger Canadian scientists to some of the most advanced space equipment available.
View a photo gallery of the Tagish Lake meteorite at the University of Alberta.
Explore 50 of Earth’s biggest meteorite impact craters with satellite images and maps.
Play games and test your knowledge of meteorites at this site devoted to the Barringer meteorite in Arizona.
Visit Planetary Science Research Discoveries (PSRD). This educational site offers the latest research on meteorites, planets, and other solar system bodies being done by NASA-sponsored scientists.