Artist’s rendition of Earth, cut away to reveal individual layers, including the deep mantle. Credit: Mingming Li/ASU
Deep below the Earth’s surface lies a thick rocky layer called the mantle, which makes up the majority of our planet’s volume. While Earth’s mantle is too deep for humans to observe directly, certain meteorites can provide clues to this unreachable layer.
In a study recently published in Science Advances , an international team of scientists — including Sang-Heon Dan Shim and Thomas Sharp of Arizona State University — has completed a complex analysis of a “shocked meteorite” (one that has experienced high-pressure and high-temperature conditions through impact events) and gained new insight into Earth’s lower mantle.
Quite a lot has been going on:
Aliens exist and could be on Earth right now, says first Briton in space Helen Sharman | The
She added that although they may not be made up of carbon and nitrogen like humans, "it's possible they're here right now and we simply can't see them".
Dr Sharman, 56, made history when she participated in a mission to the Soviet modular space station Mir in May 1991.
"There's no greater beauty than looking at the Earth from up high – and I'll never forget the first time I saw it," she said.
"After take-off we left the atmosphere and suddenly light streamed in through the window. We were over the Pacific Ocean.
Evidence for the charge disproportionation of iron in extraterrestrial bridgmanite | Science
Bridgmanite, MgSiO 3 with perovskite structure, is considered the most abundant mineral on Earth. On the lower mantle, it contains Fe and Al that strongly influence its behavior. Experimentalists have debated whether iron may exist in a mixed valence state, coexistence of Fe 2+ and Fe 3+ in bridgmanite, through charge disproportionation. Here, we report the discovery of Fe-rich aluminous bridgmanite coexisting with metallic iron in a shock vein of the Suizhou meteorite.
Here, we report the discovery of the Fe-rich analog of bridgmanite with a composition of (Fe 0.54 Mg 0.37 Al 0.15 Na 0.03 Ca 0.02 Si 0.89 )O 3 coexisting with metallic iron in a shock vein of the Suizhou meteorite. The discovery represents the first direct evidence in nature of the Fe disproportionation reaction, which so far has only been observed in some high-pressure experiments.
Eisenhower and extraterrestrials? Film explores urban legend
Written and directed by Christopher Munch, "The 11th Green" begins on slow simmer and eventually arrives at an emotional boil as it floats back and forth through time to explore a curious proposition: that former President Dwight D. Eisenhower was not only interested in but also had contact with extraterrestrials.
The film, which was partially shot in Palm Desert and other Coachella Valley locations, screens in the Locals Spotlight program at the 31st annual Palm Springs International Film Festival.
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Could invisible aliens really exist among us? An astrobiologist explains
Lecturer in Astrobiology and Principal Technical Officer at Bayfordbury Observatory, University of Hertfordshire
Samantha Rolfe does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
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If we find such a biosphere, however, it is unclear whether we should call it alien. That depends on whether we mean "of extraterrestrial origin" or simply "unfamiliar".
Happening on Twitter
Voyager scientist Ed Stone on the search for extraterrestrial life: 'We need to get back to Enceladus' https://t.co/184nBQMUbf guardian (from London) Sat Jan 11 16:15:19 +0000 2020
Astronomers often fixate on Mars, but extraterrestrial life may lie within our nearest neighbor — Venus. https://t.co/GqRHfYHS4W AstronomyMag (from Our tiny corner of the cosmos) Sat Jan 11 20:00:50 +0000 2020
Stoned Extraterrestrial Stumbles Across Hidden Message After Listening To Golden Record Backwards… https://t.co/ks1xMeXnyo TheOnion Thu Jan 09 04:51:02 +0000 2020