Mysterious asteroid the size of a dwarf planet is lurking in oursolar system

from
https://www.livescience.com/mysterio...-evidence.html

Mysterious asteroid the size of a dwarf planet is lurking in our solar
system
By Rafi Letzter - Staff Writer 4 hours ago

Where did this strange meteorite come from?

This false-color microscope image of a meteorite sample collected in
Sudan shows amphibole crystals, a unique feature, highlighted in orange.
This false-color microscope image of a meteorite sample collected in
Sudan shows amphibole crystals, a unique feature, highlighted in orange.
(Image: © Courtesy of NASA/USRA/Lunar and Planetary Institute )

There's a giant asteroid somewhere out in the solar system, and it
hurled a big rock at Earth.

The evidence for this mystery space rock comes from a diamond-studded
meteor that exploded over Sudan in 2008.

NASA had spotted the 9-ton (8,200 kilograms), 13-foot (4 meters) meteor
heading toward the planet well before impact, and researchers showed up
in the Sudanese desert to collect an unusually rich haul of remains.
Now, a new study of one of those meteorites suggests that the meteor may
have broken off of a giant asteroid — one more or less the size of the
dwarf planet Ceres, the largest object in the asteroid belt.

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Like about 4.6% of meteorites on Earth, this one — known as Almahata
Sitta (AhS) — is made of a material known as carbonaceous chondrite.
These black rocks contain organic compounds as well as a variety of
minerals and water.

The mineral makeup of these space rocks offers clues about the "parent
asteroid" that birthed a given meteor, researchers said in a statement.

"Some of these meteorites are dominated by minerals providing evidence
for exposure to water at low temperatures and pressures," study
co-author Vicky Hamilton, a planetary geologist at the Southwest
Research Institute in Boulder, Colorado, said in the statement. "The
composition of other meteorites points to heating in the absence of water."

The team analyzed a teensy 0.0018-ounce (50 milligrams) sample of AhS
under a microscope and found it had a unique mineral makeup.

The meteorite harbored an unusual suite of minerals that form at
"intermediate" temperatures and pressures (higher than what you'd find
in a typical asteroid, but lower than the inside of a planet). One
mineral in particular, amphibole also requires prolonged exposure to
water to develop.

Amphibole is common enough on Earth, but it's only appeared once before
in trace amounts in a meteorite known as Allende — the largest
carbonaceous chondrite ever found, which fell in Chihuahua, Mexico, in 1969

The high amphibole content of AhS suggests the fragment broke off a
parent asteroid that's never left meteorites on Earth before.

And samples brought back from the asteroids Ryugu and Bennu by Japan’s
Hayabusa2 and NASA’s OSIRIS-REx probes, respectively, will likely reveal
more space rock minerals that rarely turn up in meteorites, the
researchers wrote in their study.

Maybe some types of carbonaceous chondrite just don't survive the plunge
through the atmosphere as well, Hamilton said, and that's kept
scientists from studying a flavor of chondrite that might be more common
in space.

"We think that there are more carbonaceous chondrite materials in the
solar system than are represented by our collections of meteorites," she
said.

The paper was published Dec. 21 in the journal Nature Astronomy.

Originally published on Live Science.


Mysterious asteroid the size of a dwarf planet is lurking in our solar
system

On Saturday, December 26, 2020 at 2:01:13 PM UTC-8, a425couple wrote:

Where did this strange meteorite come from?

Well, let's just stop right here. Whatever it is, it is not a meteorite.

Meteorites are space rocks that fall to Earth's surface.

palsing wrote:
On Saturday, December 26, 2020 at 2:01:13 PM UTC-8, a425couple wrote:
Where did this strange meteorite come from?
Well, let's just stop right here. Whatever it is, it is not a meteorite.
Meteorites are space rocks that fall to Earth's surface.

You didnt read the article at all did you?

"The team analyzed a teensy 0.0018-ounce (50 milligrams) sample of
AhS under a microscope and found it had a unique mineral makeup."

--
[Confusing temp with temp rise:]
it's virtually impossible to keep the earth?s temperature rise to 2C,
The Earth's temperature is already in excess of 2C.
This is the same type of lazy wording as used by those who talk about
"climate deniers."
-- Wally W, 30 May 2015