Rare moon mineral found in Western Australia


Share post:

Australian scientists have discovered a rare mineral previously known only to be found in lunar rock samples and used it to date an Earth rock which formed over a billion years ago. 

Tranquillityite (red mass in blue square on left, close-up at right), a mineral previously known only from moon rocks and lunar meteorites, has been found in rocks from several sites in WA [Credit: B. Rasmussen]

Named tranquillityite after the Sea of Tranquility, where astronauts landed on the Moon in 1969, researchers discovered the substance in rocks collected from six sites in Western Australia. 

Tranquillityite was first discovered in rocks brought back from the moon soon after the first Apollo mission, along with two other substances – armalcolite and pyroxferroite. Both substances were found in Earth rocks within a decade or so of the 1969 Apollo mission but the third, tranquillityite, wasn’t found on Earth until now. 

Lead author of the recent Australian discovery, Curtin University professor and palaeontologist Birger Rasmussen, with others, wrote about the find in the journal Geology. 

He told Fairfax Media today that he got a “bit of a thrill” out of the discovery. 

“In terms of its significance perhaps it’s not a 10, perhaps it’s a 7 or something, but I got a bit of a thrill,” he said. “This was essentially the last mineral which was sort of uniquely lunar that had been found in the 70s from these samples returned from the Apollo mission.” 

According to Rasmussen, tranquillityite is “very useful” for age-dating rocks in which it is found in. 

He and fellow scientists “looked at hundreds of samples” before finding the mineral, he said. 

“We had been studying lunar rocks previously, so we’d come across tranquillityite in rocks from the moon, so we knew roughly what to look for and then we hapenned to be looking at similar types of rocks on Earth and we thought ‘this mineral should be present, we haven’t seen it – I wonder why not? We’ll keep an eye out’ and eventually we found it.”‘ 

He said it was “quite surprising” it hadn’t been found in nearly 40 years until now. “I suspect that people weren’t really looking that hard I suppose.” 

The discovery of tranquillityite in certain rocks also helped him and fellow scientists give an age to the rocks underneath rocks with tranquillityite in them, which Rasmussen said were previously thought to be much younger. 

Although there are alternative ways to date rocks, the minerals required to date them aren’t always present, Rasmussen said. “So having another mineral such as tranquillityite, which has very useful properties for dating – it [adds] another string to your bow.” 

Author: Ben Grubb | Source: The Age [January 04, 2012]



Related articles

Royal temple excavated in NE China

The ruins of the town of Baoma, on a hill in Antu County in northeast China's Jilin Province,...

Mexico Mayan site gets double heritage status

The southern Mexico Mayan ruins of Calakmul have become the country's first site to receive the "mixed" World...

Faintest hisses from space reveal famous star’s past life

Astronomers have managed to peer into the past of a nearby star millions of years before its famous...

Cassini sees precursors to aerosol haze on Titan

Scientists working with data from NASA's Cassini mission have confirmed the presence of a population of complex hydrocarbons...

After the birds vanish, plants are next to go

The first evidence that the loss of a bird species could damage the prospects of particular plants has...

Searching underwater for history of the Roman Empire

Stanford scholar Justin Leidwanger spends a lot of time underwater. An assistant professor of classics, Leidwanger is a...

An important discovery of marine fossils in China

In a recent study, large numbers of bryozoan and other typical marine fossils were discovered for the first...

The primate brain is ‘pre-adapted’ to face potentially any situation

Scientists have shown how the brain anticipates all of the new situations that it may encounter in a...