Wednesday June 19, 2019
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Scientists Found Earth’s Oldest Rock on Moon

The final impact event to affect this sample occurred about 26 million years ago, when an impacting asteroid hit the Moon

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Analysis of lunar samples from the Apollo 14 mission shows that a large impacting asteroid or comet hurtled a piece of Earth rock, about 4 billion years ago, on to the Moon’s surface.

An international team of scientists led by NASA’s Center for Lunar Science and Exploration (CLSE), found evidence that the impact jettisoned material through Earth’s primitive atmosphere, into space, where it collided with the surface of the Moon (which was three times closer to Earth than it is now) about 4 billion years ago.

The rock was subsequently mixed with other lunar surface materials into one sample.

The 2 gram fragment of rock was composed of quartz, feldspar, and zircon — all commonly found on Earth and highly unusual on the Moon.

Earth depletion
Earth depletion, Pixabay

“It is an extraordinary find that helps paint a better picture of early Earth and the bombardment that modified our planet during the dawn of life,” said David A. Kring, Principal Investigator at CLSE.

It is possible that the sample is not of terrestrial origin, but instead crystallised on the Moon.

That would, however, require the sample to have formed at tremendous depths, in the lunar mantle, where very different rock compositions are anticipated and in the reducing and higher temperature conditions characteristic of the Moon.

But chemical analysis of the rock fragment shows it crystallised in a terrestrial-like oxidised system, at terrestrial temperatures, according to research published in the journal Earth and Planetary Science Letters.

rocks
Earth’s oldest known evolved rocks result of asteroids. Pixabay

Further, the researchers revealed that the rock crystallised about 20 kilometres beneath the Earth’s surface 4-4.1 billion years ago. It was then excavated by one or more large impact events and launched into cislunar space.

Once the sample reached the lunar surface, it was affected by several other impact events, one of which partially melted it 3.9 billion years ago, and which probably buried it beneath the surface.

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The sample is therefore a relic of an intense period of bombardment that shaped the solar system during the first billion years. After that period, the Moon was affected by smaller and less frequent impact events.

The final impact event to affect this sample occurred about 26 million years ago, when an impacting asteroid hit the Moon, producing the small 340 meter-diameter Cone Crater, and excavating the sample back onto the lunar surface where astronauts collected it almost exactly 48 years ago (January 31-February 6, 1971), Kring explained. (IANS)

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Scientists Take Peek Behind Those Sad Puppy Dog Eyes and Find a Unique Muscle

Pooches use the muscle to raise their eyebrows and make the babylike expression

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Scientists, Sad, Puppy
FILE - Lexy, a therapy dog, is seen at Fort Bragg, N.C., Feb. 18, 2014. A study released June 17, 2019, suggests that over thousands of years of dog domestication, people preferred dogs that could pull off the "puppy dog" eyes look. VOA

What’s behind those hard-to-resist puppy dog eyes?

New research suggests that over thousands of years of dog domestication, people preferred pups that could pull off that appealing, sad look. And that encouraged the development of the facial muscle that creates it.

Today, pooches use the muscle to raise their eyebrows and make the babylike expression. That muscle is virtually absent in their ancestors, the wolves.

“You don’t typically see such muscle differences in species that are that closely related,” said Anne Burrows of Duquesne University in Pittsburgh, an author of the study released Monday by the Proceedings of the National Academy of Sciences.

Scientists, Sad, Puppy
FILE – A female red wolf emerges from her den sheltering newborn pups at the Museum of Life and Science in Durham, N.C., May 13, 2019. VOA

Dogs differ from wolves in many ways, from having shorter snouts, smaller sizes and more expressive faces. And unlike wolves, dogs heavily rely on human eye contact, whether to know when someone’s talking to them or when they can’t solve a problem, like hopping a fence or getting out the door.

Burrows and her colleagues examined the eye muscles in the cadavers of six dogs and two wolves. They found dogs have a meaty eye muscle to lift their eyebrows and make puppy dog eyes. But in wolves, the same muscle was stringy or missing.

The scientists also recorded 27 dogs and nine wolves as each stared at a person. Pet pooches frequently and intensely pulled back their eyebrows to make sad expressions, while the wolves rarely made these faces, and never with great intensity.

The researchers believe dogs, over their relatively short 33,000 years of domestication, used this eye muscle to communicate, possibly goading people to feed or care for them — or at least take them out to play. And people, perhaps unwittingly, obliged.

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‘Profound’ implications

Dog experts not involved with the study were impressed.

“The implications are quite profound,” said Brian Hare from Duke University, who edited the article. Hare wrote in an email that these muscles almost certainly developed because they gave dogs an advantage when interacting with people, and people have been unaware of it.

“The proof has been in their puppy dog eyes all this time!” he said.

Scientists, Sad, Puppy
Over thousands of years of dog domestication, people preferred pups that could pull off that appealing, sad look. Pixabay

Evan MacLean at the University of Arizona called the findings fascinating, but cautioned that the muscle difference could be an indirect effect of other changes rather than a specific response to human influence.

Clive Wynne of the Canine Science Collaboratory at Arizona State University said: “Kudos to the researchers for thinking of a cool way to investigate an important aspect of dogs’ success” with humans.

But he noted in an email that the study has a few snags, particularly the small sampling — only five dog breeds were examined and videos were mainly of Staffordshire bull terriers — and the lack of background information about each animal.

“Did these wolves regularly meet people bearing gifts that might be worth asking for with an endearing face?” he asked.

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Burrows said she planned follow-up studies to examine more breeds. (VOA)