Archive for the ‘asteroid/comet impacts’ category

Feb 26, 2023

Astrophysicists Chart Source of Asteroid That Killed Dinosaurs

Posted by in categories: asteroid/comet impacts, existential risks, physics

A new model explains a possible route for the extraterrestrial rock before it blasted Earth.

Feb 21, 2023

Glycine Peptide Chain Formation in the Gas Phase via Unimolecular Reactions

Posted by in categories: asteroid/comet impacts, existential risks

Peptide chain formation from amino acids such as glycine is a key step in the emergence of life. Unlike their synthesis by living systems, how peptide chains grow under abiotic conditions is an open question given the variety of organic compounds discovered in various astrophysical environments, comets and meteorites. We propose a new abiotic route in the presence of protonated molecular dimers of glycine in a cold gaseous atmosphere without further need for a solid catalytic substrate. The results provide evidence for the preferential formation of mixed protonated dimers of glycine consisting of a dipeptide and a glycine molecule instead of pure protonated glycine dimers. Additional measurements mimicking a cosmic-ray impact in terms of internal excitation show that a single gas-phase collision induces polymerization via dehydration in both the mixed and pure dimer ions.

Feb 21, 2023

ARES: NASA is examining reports of an atmospheric fireball about 6 p.m. EST, Feb. 15, near McAllen, Texas

Posted by in categories: asteroid/comet impacts, existential risks

Based on analysis of preliminary information from several sources, NASA experts believe the object was a meteoroid about two feet in diameter weighing about 1,000 pounds. The angle and speed of entry, along with signatures in weather radar imagery, are consistent with other naturally occurring meteorite falls. Radar and other data indicate that meteorites did reach the ground from this event.

Although meteorites tend to hit Earth’s atmosphere at high speeds, they slow as they travel through the atmosphere, breaking into small fragments before hitting the ground. Meteorites cool rapidly and generally are not a risk to the public.

Feb 19, 2023

NASA’s planetary radar captures detailed view of oblong asteroid

Posted by in categories: asteroid/comet impacts, existential risks

On Feb. 3, an asteroid more than three times as long as it is wide safely flew past Earth at a distance of about 1.1 million miles (1.8 million kilometers, or a little under five times the distance between the Moon and Earth). While there was no risk of the asteroid—called 2011 AG5—impacting our planet, scientists at NASA’s Jet Propulsion Laboratory in Southern California closely tracked the object, making invaluable observations to help determine its size, rotation, surface details, and, most notably, shape.

This provided the first opportunity to take a detailed look at the asteroid since it was discovered in 2011, revealing an object about 1,600 feet (500 meters) long and about 500 feet (150 meters) wide—dimensions comparable to the Empire State Building. The powerful 230-foot (70-meter) Goldstone Solar System Radar antenna dish at the Deep Space Network’s facility near Barstow, California, revealed the dimensions of this extremely elongated asteroid.

“Of the 1,040 near-Earth objects observed by planetary to date, this is one of the most elongated we’ve seen,” said Lance Benner, principal scientist at JPL who helped lead the .

Feb 12, 2023

Turkey earthquake opened 190-mile-long fissure, satellite images show

Posted by in categories: asteroid/comet impacts, existential risks

Two enormous cracks in Earth’s crust opened near the Turkish-Syrian border after two powerful earthquakes shook the region on Monday (Feb. 6), killing over 20,000 people.

Researchers from the U.K. Centre for the Observation & Modelling of Earthquakes, Volcanoes & Tectonics (COMET) found the ruptures by comparing images of the area near the Mediterranean Sea coast taken by the European Earth-observing satellite Sentinel-1 before and after the devastating earthquakes.

The longer of the two ruptures stretches 190 miles (300 kilometers) in the northeastern direction from the northeastern tip of the Mediterranean Sea. The crack was created by the first of the two major tremors that hit the region on Monday, the more powerful 7.8-magnitude earthquake that struck at 4:17 a.m. local time (8:17 p.m. EST on Feb. 5). The second crack, 80 miles long (125 km), opened during the second, somewhat milder 7.5-magnitude temblor about nine hours later, COMET said in a tweet on Friday (Feb. 10).

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Feb 9, 2023

We May Have Had an Interstellar Visitor for Eons and Scientists Are Stumped

Posted by in categories: asteroid/comet impacts, existential risks

“I think it’s going to be inconclusive, if not impossible to demonstrate conclusively,” one physicist said of the possible interstellar comet.

Feb 8, 2023

Examining an asteroid impact in slow motion

Posted by in categories: asteroid/comet impacts, existential risks

For the first time, researchers have recorded live and in atomic detail what happens to the material in an asteroid impact. The team of Falko Langenhorst from the University of Jena and Hanns-Peter Liermann from DESY simulated an asteroid impact with the mineral quartz in the lab and pursued it in slow motion in a diamond anvil cell, while monitoring it with DESY’s X-ray source PETRA III.

The observation reveals an intermediate state in that solves a decades-old mystery about the formation of characteristic lamellae in material hit by an asteroid. Quartz is ubiquitous on the Earth’s surface, and is, for example, the major constituent of sand. The analysis helps to better understand traces of past impacts, and may also have significance for entirely different materials. The researchers present their findings in Nature Communications.

Asteroid impacts are that create huge craters and sometimes melt parts of Earth’s bedrock. “Nevertheless, craters are often difficult to detect on Earth, because erosion, weathering and cause them to disappear over millions of years,” Langenhorst explains.

Jan 29, 2023

Scientists Warn Giant Asteroid Is Actually Swarm, Nearly Impossible to Destroy

Posted by in categories: asteroid/comet impacts, existential risks

Researchers have found that some asteroids that are largely made from small pieces of rubble could be very difficult to deflect if one were to ever hurtle towards Earth, a terrifying finding that could force us to reconsider our asteroid defense strategies.

It’s an especially pertinent topic considering NASA’s recent successful deflection of asteroid Didymos by smashing its Double Asteroid Reduction Test (DART) spacecraft into it last year, a proof of concept mission meant to investigate ways for humanity to protect itself from asteroid threats.

Jan 27, 2023

“Extraordinary” video shows asteroid passing “extremely” close to Earth

Posted by in categories: asteroid/comet impacts, existential risks

An astronomer has captured “extraordinary” footage of an asteroid that made an “extremely close” approach to the Earth on Thursday.

The space rock, known as 2023 BU, zoomed over the southern tip of South America yesterday, while it was only around 2,200 miles above the surface of the Earth.

This is one of the closest approaches of an near-Earth object ever recorded. Data from NASA’s Center for Near Earth Object Studies showed that the flyby of 2023 BU was the fourth-nearest of more than 35,000 past and future Earth close approaches in the 300-year period from 1900 to 2200.

Continue reading “‘Extraordinary’ video shows asteroid passing ‘extremely’ close to Earth” »

Jan 25, 2023

“Rubble pile” asteroids may be surprisingly hard to destroy — study

Posted by in categories: asteroid/comet impacts, existential risks

When Japan’s Hayabusa mission traveled to asteroid Itokawa, it collected samples. These successfully reached Earth in 2010.

Near Earth asteroid Itokawa is a rubble pile that formed more than four billion years ago, a new study found. So, these asteroids might be resilient to demise.

Continue reading “‘Rubble pile’ asteroids may be surprisingly hard to destroy — study” »

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