Last updated July 16, 2019 at 4:41 pm
While some moon rocks are on public display – including one in Australia that you can touch – NASA has a secret stash yet to be opened.
The world may be fast approaching the fiftieth anniversary of Apollo 11’s 1969 flight to the moon, but the samples brought back by it and NASA’s five subsequent landings remain fresh and exciting, scientists say.
The six missions brought back 381 kilograms of material, but NASA has been cautious about doling them out for research and display.
Some have been turned over to scientists for research, revealing incredible secrets about the interlinked histories of the Earth and Moon. And others have been gifted to countries to display, inspiring generations.
Australia has its own collection – with five moon rocks on public display in Canberra alone.
Geoscience Australia holds Sample 70215 collected by Apollo 17, the only moon rock in the southern hemisphere that the public is allowed to touch.
Also in the nation’s capital is a rock brought back by Aldrin, Collins and Armstrong on Apollo 11, on display at Questacon. In addition, the Canberra Deep Space Communication Complex holds Sample 10072,80, a 147.25 gram fragment which is the largest on display in Australia.
Other moon rocks are on display at the National Museum of Australia and Mount Stromlo Observatory.
Secret stash reserved for the future
However, NASA have also kept a selection of the rocks under lock and key as an investment for future scientists. Since the 1970’s, they’ve preserved much of its moon-rock archive until the development of analytical methods more capable than those possible when the samples were collected.
Advances in knowledge have allowed today’s lunar scientists to examine the rocks with a more detailed understanding of the information they are trying to pry out of them.
For example, remote sensing and geological mapping of the moon has helped put the Apollo samples in perspective, says Charles Shearer of the University of New Mexico.
Shearer gave a detailed rundown on the possibilities inherent in the rocks at the Lunar and Planetary Science Conference in The Woodlands, Texas.
This allows scientists to reexamine previously studied samples with greater understanding of the conditions under which they formed.
“We continue to see new information by looking at Apollo samples really carefully,” adds Juliana Gross, of Rutgers University, New Jersey.
The Moon isn’t just the Moon
For example, she says, studies of these samples have found that not everything in them is originally from the moon.
A recent study revealed that one of Apollo’s moon rocks contained a pebble that appears to be a four-billion-year-old chip blasted off the Earth’s surface, making it one of the oldest Earth rocks ever collected.
Other moon rocks have also proven to contain other “exogenic” fragments from other sources, Gross says.
“[Moon rocks] are not only giving us information about the moon itself, but also about the material that was delivered to the Earth/moon system,” she says.
This helps reveal the history not only of the moon, but the entire solar system.
“New and higher precision techniques will continue to reveal more information,” she adds.
Already, Gross says, it’s possible to look into the history of a single grain of a lunar rock and see how its crystalline structure has been disrupted by ancient shocks — something that can be used to trace the impact history of the landscape where the rock formed.
It’s also now possible to study magnetic signatures in the grains in sufficient detail to learn about the state of the early lunar core and its magnetic dynamo.
What this means, says Shearer, is that after 50 years, “we still have ‘new’ Apollo samples to examine now and for future generations”.
Samples sealed on the Moon and never opened
And that’s just the beginning. There even exist samples that were sealed on the moon, returned to Earth … and never opened.
This summer, Shearer notes, a project called the Apollo Next Generation Sample Analysis program intends to open one of them.
Precise scheduling is still uncertain, but funding has been approved, and once the scientists on the team are all in agreement and final approval is granted by the Astromaterials Acquisition and Curation Office at NASA’s Johnson Space Centre in Houston, it will probably proceed sometime this summer, right around the half-century anniversary of Apollo 11.
The material comes from the final mission in the series, Apollo 17, which landed in December 1972. It is a core sample, obtained by pounding a collection tube into the lunar surface above a suspected fault line that might have allowed gas from deeper down to percolate upward.
The tube’s container had a special indium-silver cap that, the 1972 engineers hoped, would be able to seal the stuff in its pristine state long enough for analytical methods to evolve to the point where it could be properly studied.
That is, until now.
“One should maybe consider this a new mission to the moon,” Shearer says.
The outcome will depend partly on how well NASA’s indium/silver cap worked, and partly on whether there ever were volatiles in the sample.
But whatever it teaches us about the Moon, it will also help us understand how best to handle (and dole out) samples from other sample-return missions, whether they be to the asteroids (link my story), returns to the Moon, or a long-dreamed-of sample-return mission to Mars.
“These samples truly are the gift that keeps on giving,” says Shearer.
Exploring Canberra’s Moon Rock Trail
Australia’s moon rock hotspot has thrown open its doors, with Canberra locals and visitors able to see and touch five lunar samples along the Moon Rock Trail.
The trail has stops at Geoscience Australia, the National Museum of Australia, Questacon, CSIRO-managed Canberra Deep Space Communication Complex at Tidbinbilla, and the Mount Stromlo Observatory.
The samples include the only piece of the Moon in the Southern Hemisphere that can be actually touched, the largest piece of Apollo 11 returned Moon rock in the Southern Hemisphere, Australian flags flown to the surface of the Moon, fragments of lunar rock gifted to Australia for our important role in the Apollo missions, and the chance to walk across the face of the Moon on one of Canberra’s highest peaks.
Beginning on the shores of Lake Burley-Griffin, the National Museum of Australia has a lunar sample on display as part of its Tracking Apollo: 50 years since the Moon landing exhibit. Sample 70017, also known as the goodwill rock, was returned on the Apollo 17 mission. Originally weighing 3kg, the billions-of-years-old rock was split into 135 fragments and distributed around the world as a message of peace. Our piece was given in recognition of Australia’s role in the Apollo program, providing tracking stations which maintained communications with spacecraft.
Just a stones throw away (please don’t throw moon rocks) at Questacon is a fragment brought back by Aldrin, Armstrong and Collins on Apollo 11. Next to the rock is an Australian flag that the NASA crew took with them on their historic 1.5 million kilometre journey.
Heading into the southern suburbs of Canberra to Geoscience Australia’s headquarters provides an absolutely unique opportunity – the chance to actually touch part of the moon. Sample 70215 is one of only 11 touchstones in the world – moon rocks open to be touched and felt by the public.
“We’re really privileged to be the only place in the Southern Hemisphere where visitors can now touch a Moon rock that was specially brought back from an Apollo mission, rather than a piece that fell to Earth as a meteorite,” says Steve Petkovski, Geoscience Australia’s Curator.
From there, head west into the mountains to ANU’s Mt Stromlo Observatory. There, follow in the footsteps of other astronauts at the Mt Stromlo Observatory with the ANU Moon sculpture.
“One of the hidden gems of the ANU Mt Stromlo Observatory is our Moon sculpture, which recreates the side of our nearest neighbour in the solar system,” says Brad Tucker, an astrophysicist at ANU.
“Our Moon sculpture allows you to not only touch a piece of the Moon but to walk on it – experiencing first-hand the wonders of space and what it is like to take one small step, and one giant leap.”
The final stop on the moon trail is the Canberra Deep Space Communication Complex at Tidbinbilla. Managed by the CSIRO on NASA’s behalf, the facility maintains communications with spacecraft deep into space, including the Voyager pair on the edge of the solar system.
Their lunar sample (10072,80), weighs in at a hefty 147.25 grams, and is the largest Moon rock on public display in Australia.
“At 3.8 billion years old, this rock has been on a long journey from the Moon to the Earth. It was gifted to Australia to symbolise the close links that we have in space exploration with the United States and between CSIRO and NASA,” says facility director Ed Kruzins.
The Moon Rock Trail locations are available on Google Maps: bit.ly/MoonTrail
Additional reporting by Ben Lewis