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Wed, 18 May 2022
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Evidence of extinction event could be at the bottom of a South Carolina pond

Researchers say they've found evidence that an asteroid or comet exploded over Kershaw County thousands of years ago, causing huge changes to life in that area.
Excavation Site
© Christopher Moore
ELGIN, S.C. — A lot of attention has been generated in the South Carolina town of Elgin following the earthquakes there in recent months. But Elgin is also making headlines for a stunning discovery made by a former University of South Carolina archaeologist, Christopher Moore, and his team of researchers.

Moore and his team of researchers believe they've found signs supporting an extinction theory called the Younger-Dryas Impact Hypothesis. And they've found evidence that appears to shows an asteroid or comet exploded over Kershaw County thousands of years ago, causing huge changes to life in that area..

"I wanted to come to White Pond because I knew the mud and the sediments in the pond had a record of climate over the last at least 20 or 30,000 years," Moore explained.

The Younger-Dryas Impact Hypothesis states an asteroid or comet hit the Earth nearly 13,000 years ago, splintering into smaller parts over the skies of several continents. The result led to a decline in animal and human populations. Evidence in support of the proposition, Moore said, was found at the bottom of White Pond in Elgin in recent years.

"Well when you dig down in certain areas you're going back in time," Moore said. "So you start at the surface and you have the most recent time periods, and as you go down, it's like a time capsule, and you're going further back in time."

Teams excavated in three or four feet long block units--individual segments where the Earth is peeled back--across parts of the White Pond area. Moore said at the deepest part of the block they've found artifacts that are 12,000 years old.

Comet 2

New Comet C/2022 F1 (ATLAS)

CBET 5112 & MPEC 2022-G82, issued on 2022, April 06, announce the discovery of a comet (magnitude ~18.5) on CCD images taken on Mar. 30.3 UT with a 0.5-m f/2 Wright-Schmidt reflector at Rio Hurtado, Chile, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. The new comet has been designated C/2022 F1 (ATLAS).

Stacking of 20 unfiltered exposures, 90 seconds each, obtained remotely on 2022, April 2.4 from X02 (Telescope Live, Chile) through a 0.61-m f/6.5 astrograph + CCD, shows that this object is a comet with a compact coma about 9" arcsecond in diameter (Observers E. Bryssinck, M. Rocchetto, E. Guido, M. Fulle, G. Milani, G. Savini, A. Valvasori).

Our confirmation image (click on the images for a bigger version)
C/2022 F1 Atlas
© Remanzacco Blogspot

Fireball 5

Loud meteor fireball spotted over southern Mississippi mostly heard, hardly seen

A fiery meteor streaked across the morning skies in southern Mississippi yesterday on April 27, 2022.

More than 30 eyewitnesses in the states of Arkansas, Louisiana and Mississippi reported seeing a bright fireball at 8:03 a.m. CDT. The sighting was soon followed by numerous reports of loud booms heard in Claiborne County, Mississippi, and surrounding counties.
GLM image from the GOES 16 satellite.
© NOAA
GLM image from the GOES 16 satellite.
Approximately 22,000 miles out in space, NOAA's Geostationary Lightning Mappers (GLM) onboard the Geostationary Operational Environmental Satellites (GOES) 16 and 17 detected several bright flashes associated with the fragmentation's of this bolide, or exceptionally bright meteor, which was first spotted 54 miles above the Mississippi River near the Mississippi town of Alcorn.

"This is one of the nicer events I have seen in the GLM data," said Bill Cooke, lead of NASA's Meteoroid Environments Office at Marshall Space Flight Center in Huntsville, Alabama.

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Massive meteorite impact created the hottest mantle rock ever

Lake Mistastin
© Planet Observer/Universal Images Group via Getty Images
The rock was found within the Mistastin impact crater in Labrador, Canada, shown here in this satellite image.
It's confirmed: The hottest rock ever discovered in Earth's crust really was super-hot.

The rock, a fist-sized piece of black glass, was discovered in 2011 and first reported in 2017, when scientists wrote in the journal Earth and Planetary Science Letters that it had been formed in temperatures reaching 4,298 degrees Fahrenheit (2,370 degrees Celsius), hotter than much of the Earth's mantle. Now, a new analysis of minerals from the same site reveals that this record-scorching heat was real.

The rocks melted and reformed in a meteorite impact about 36 million years ago in what is today Labrador, Canada. The impact formed the 17-mile-wide (28 kilometers) Mistastin crater, where Michael Zanetti, then a doctoral student at Washington University St. Louis, picked up the glassy rock during a Canadian Space Agency-funded study of how to coordinate astronauts and rovers working together to explore another planet or moon. (Mistastin crater looks a lot like a moon crater and is often used as a stand-in for such research.)

The chance find turned out to be an important one. An analysis of the rock revealed that it contained zircons, extremely durable minerals that crystallize under high heat. The structure of zircons can show how hot it was when they formed.

But to confirm the initial findings, researchers needed to date more than one zircon. In the new study, lead author Gavin Tolometti, a postdoctoral researcher at Western University in Canada, and colleagues analyzed four more zircons in samples from the crater. These samples came from different types of rocks in different locations, giving a more comprehensive view of how the impact heated the ground. One was from a glassy rock formed in the impact, two others from rocks that melted and resolidified, and one from a sedimentary rock that held fragments of glass formed in the impact.

Fireball 4

An interstellar object exploded over Earth in 2014, declassified government data reveal

Classified data prevented scientists from verifying their discovery for 3 years.
Meteor Fireball
A fireball that blazed through the skies over Papua New Guinea in 2014 was actually a fast-moving object from another star system, according to a recent memo(opens in new tab) released by the U.S. Space Command (USSC).

The object, a small meteorite measuring just 1.5 feet (0.45 meter) across, slammed into Earth's atmosphere on Jan. 8, 2014, after traveling through space at more than 130,000 mph (210,000 km/h) — a speed that far exceeds the average velocity of meteors that orbit within the solar system, according to a 2019 study of the object published in the preprint database arXiv.

That 2019 study argued that the wee meteor's speed, along with the trajectory of its orbit, proved with 99% certainty that the object had originated far beyond our solar system — possibly "from the deep interior of a planetary system or a star in the thick disk of the Milky Way galaxy," the authors wrote. But despite their near certainty, the team's paper was never peer-reviewed or published in a scientific journal, as some of the data needed to verify their calculations was considered classified by the U.S. government, according to Vice (opens in new tab).

Now, USSC scientists have officially confirmed the team's findings. In a memo dated March 1 and shared on Twitter on April 6, Lt. Gen. John E. Shaw, deputy commander of the USSC, wrote that the 2019 analysis of the fireball was "sufficiently accurate to confirm an interstellar trajectory."

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Space Force releases decades of data on meteor fireballs

Impact Data by NASA
© NASA JPL CNEOS and U.S. Space Force's Space Operation's Center.
Screen capture from NASA JPL CNEOS’ Fireball webpage depicting data collected by U.S. government sensors of impact in atmosphere by small 2 meter asteroid 2022 EB5 on March 11, 2022.
An agreement between NASA and the U.S. Space Force recently authorized the public release of decades of data collected by U.S. government sensors on fireball events (large bright meteors also known as bolides) for the benefit of the scientific and planetary defense communities. This action results from collaboration between NASA's Planetary Defense Coordination Office (PDCO) and the U.S. Space Force to continue furthering our nation's efforts in planetary defense, which include finding, tracking, characterizing, and cataloguing near-Earth objects (NEOs). The newly released data is comprised of information on the changing brightness of bolides as they pass through Earth's atmosphere, called light curves, that could enhance the planetary defense community's current ability to model the effects of impacts by larger asteroids that could one day pose a threat to Earth.

Bolides, very bright meteors that can even be seen in daylight, are a regular occurrence - on the order of several dozen times per year - that result when our planet is impacted by asteroids too small to reach the ground but large enough to explode upon impact with Earth's atmosphere. U.S. government sensors detect these atmospheric impact events, and the bolide data is reported to the NASA Jet Propulsion Laboratory's Center for Near Earth Object Studies (CNEOS) fireballs database, which contains data going back to 1988 for nearly one thousand bolide events. Now, planetary defense experts will have access to even more detailed data - specifically, light curve information that captures the optical intensity variation during the several seconds of an object's breakup in the atmosphere. The data will be available to scientists as soon as it is properly archived, with the reported events and made easily accessible. This uniquely rich data set has been greatly sought after by the scientific community as an object's breakup in Earth's atmosphere provides scientific insight into the object's strength and composition based on what altitudes at which it breaks up and disintegrates. The approximate total radiated energy and pre-entry velocity vector (i.e., direction) can also be better derived from bolide light curve data.

"The growing archive of bolide reports, as posted on the NASA CNEOS Fireballs website, has significantly increased scientific knowledge and contributes to the White House approved National Near-Earth Object Preparedness Strategy and Action Plan" said Lindley Johnson, planetary defense officer at NASA Headquarters. "The release of these new bolide data demonstrates another key area of collaboration between NASA and the U.S. Space Force and helps further the pursuit of improved capabilities for understanding these objects and our preparedness to respond to the impact hazard NEOs pose to Earth."

Comet 2

New Comet C/2022 E3 (ZTF)

CBET 5111 & MPEC 2022-F13, issued on 2022, March 21, announce the discovery of an apparently asteroidal object (magnitude ~17) discovered on CCD images taken on Mar. 2 UT with a 1.2-m f/2.4 Schmidt telescope at Palomar in the course of the "Zwicky Transient Facility" (ZTF) survey (MPC code I41). Subsequently, it has been found to show cometary appearance by CCD astrometrists elsewhere. The new comet has been designated C/2022 E3 (ZTF).

Stacking of 12 unfiltered exposures, 120 seconds each, obtained remotely on 2022, March 20.4 from X02 (Telescope Live, Chile) through a 0.61-m f/6.5 astrograph + CCD, shows that this object is a comet with a compact coma about 9" arcsecond in diameter (Observers E. Guido, M. Rocchetto, E. Bryssinck, G. Milani, G. Savini, A. Valvasori).

Our confirmation image (click on the images for a bigger version; made with TYCHO software by D. Parrott)
C/2022 E3 ZTF
© Remanzacco Blogspot

Comet 2

New Comet C/2022 E2 (ATLAS)

CBET 5109 & MPEC 2022-E227, issued on 2022, March 15, announce the discovery of an apparently asteroidal object (magnitude ~19) discovered on CCD images taken on Mar. 7 UT with a 0.5-m f/2 Schmidt reflector at Rio Hurtado, Chile, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. Subsequently, it has been found to show cometary appearance by CCD astrometrists elsewhere after it was posted on the Minor Planet Center's PCCP webpage. The new comet has been designated C/2022 E2 (ATLAS).

Stacking of 25 unfiltered exposures, 120 seconds each, obtained remotely on 2022, March 10.3 from X02 (Telescope Live, Chile) through a 0.61-m f/6.5 astrograph + CCD, shows that this object is a comet with a compact coma about 7" arcsecond in diameter (Observers E. Guido, M. Rocchetto, E. Bryssinck, G. Milani, G. Savini, A. Valvasori).

Our confirmation image (click on the images for a bigger version; made with TYCHO software by D. Parrott)
Comet C/2022 E2 (ATLAS)
© Remanzacco Blogspot

Fireball 4

Small asteroid 2022 EB5 tracked hitting Earth's atmosphere on March 11

Asteroid 2022 EB5
© K. Sarneczky
On 2022 March 11.80, K. Sarneczky found a small asteroid using the 0.60-m Schmidt + CCD of GINOP-KHK, Piszkesteto (K88 MPC code) that was soon after put on the NEOCP list with the provisional designation Sar2593 for the follow-up by other observers. The Minor Planet Center subsequently assigned the following official designation to this object 2022 EB5.

Discovery images (19:25UT) of asteroid 2022 EB5

Credit: K. Sarneczky

At 20:46UT of March 11, Bill Gray sent an alert in the MPML mailing list about the impact of Sar2593 with the Earth's atmosphere and: "to urge European observers to take a look for this object, currently on NEOCP. It should come in at 21:23 UTC at latitude +70.47, longitude W 10.40, plus or minus a few dozen km. That's about forty minutes from "right now", a bit north of Iceland". Below you can see a map of the impact location as calculated by Gray, southwest of Jan Mayen island.
Jan Mayen island
© B.Gray

Comment: To be clear, by 'impact', in this case, they mean that it detonated high up in the atmosphere as a meteor fireball.


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Hiawatha crater in Greenland older than thought

Greenland Ice Sheet
© Pierre Beck
Fieldwork at the edge of the Greenland Ice Sheet in 2019.
Danish and Swedish researchers have dated the enormous Hiawatha impact crater, a 31 km-wide asteroid crater buried under a kilometer of Greenlandic ice. The dating ends speculation that the asteroid impacted after the appearance of humans and opens up a new understanding of Earth's evolution in the post-dinosaur era.

Ever since 2015, when researchers at the University of Copenhagen's GLOBE Institute discovered the Hiawatha impact crater in northwestern Greenland, uncertainty about the crater's age has been the subject of considerable speculation. Could the asteroid have slammed into Earth as recently as 13,000 years ago, when humans had long populated the planet? Could its impact have catalyzed a nearly 1,000-year period of global cooling known as the Younger Dryas?

New analyses performed on grains of sand and rocks from the Hiawatha impact crater by the Natural History Museum of Denmark and the GLOBE Institute at the University of Copenhagen, as well as the Swedish Museum of Natural History in Stockholm, demonstrate that the answer is no. The Hiawatha impact crater is far older. In fact, a new study published in the journal Science Advances today reports its age to be 58 million years old.

"Dating the crater has been a particularly tough nut to crack, so it's very satisfying that two laboratories in Denmark and Sweden, using different dating methods arrived at the same conclusion. As such, I'm convinced that we've determined the crater's actual age, which is much older than many people once thought," says Michael Storey of the Natural History Museum of Denmark.