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The Younger Dryas impact hypothesis, also known as Clovis comet hypothesis, posits that the hemisphere-wide debris field of a large, disintegrating asteroid (or comet) struck North America, South America, Europe, and western Asia approximately 12,800 years ago. This event triggered extensive biomass burning, brief impact winter, climate change, and contributed to extinctions of late Pleistocene megafauna. Controversial from the time it was proposed, this hypothesis continues to be contested by those who prefer to attribute the end-Pleistocene reversal in (global) warming entirely to terrestrial causes. Now, University of California, Santa Barbara’s Professor James Kennett and co-authors present further geologic and...

Had there been eyewitnesses, we'd have known about the Bering blast within minutes, but it happened beneath the cloud deck in a sparsely populated region off the east coast of Russia's Kamchatka Peninsula (58.6°N, 174.2°W). Military satellites designed to look for nuclear explosions picked up the blast, as did more than 16 infrasound detectors worldwide. Luckily for us, so did the Japanese Himawari 8 satellite, which took striking images of the sooty trail of dust ablated from the meteoroid during its atmospheric passage.

Almost nobody noticed this, but back in December a chunk of space rock slammed into the Earth's atmosphere at 32km/sec over the Bering sea. The aerodynamic forces tore it apart and it released energy equivalent to a 170 kiloton weapon. And almost nobody noticed. Find out more about the asteroid hazard and how you can help at the B612 Foundation. | 173 Kiloton Explosion Over Bering Sea Was Asteroid Breaking Up | Scott Manley | Published on Mar 19, 2019

A kilometer-size asteroid slammed into Earth about 800,000 years ago with so much force that it scattered debris across a 10th of our planet's surface. Yet its impact crater remains undiscovered. Now, glassy remains believed to have come from the strike suggest the asteroid hit southeast Asia as our close ancestors walked the Earth... Aaron Cavosie, an astrobiologist and geochemist at Curtin University in Perth, Australia, and his colleagues examined the chemical composition of three tektites from Thailand. They searched for evidence of reidite, a rare mineral formed only by extreme pressures and temperatures, like those of an asteroid impact....

UC Berkeley scientists have obtained more precise dates for the Deccan Traps volcanic lava flows, linking peak activity more closely to the asteroid or comet impact 66 million years ago and the coincident mass extinction. But if greenhouse gases emitted before the impact created a hothouse climate that set life up for a fall when the impact cooled the planet, those gases did not coincide with the largest lava flows from the Deccan Traps. Based on new data published today in the journal Science, it seems increasingly likely that an asteroid or comet impact 66 million years ago reignited massive...

Following the discovery of the 19.2-mile wide Hiawatha impact crater beneath the northwest margin of the Greenland Ice Sheet, Dr. Joe MacGregor of NASA’s Goddard Space Flight Center and colleagues explored satellite and aerogeophysical data in search of additional such craters and found a possible second impact crater that is 22.7 miles wide and 114 miles southeast of the Hiawatha crater. The discovery is described in a paper in the journal Geophysical Research Letters. ..." Following the finding of that first crater, Dr. MacGregor and co-authors checked topographic maps of the rock beneath Greenland’s ice for signs of other craters....

Normal faults are generated throughout the crater from the impact force. Fault blocks form along the crater walls, breaking off and sliding back into the crater following impact. Rocks around the crater rim fill in much of the crater as it collapses. Furthermore, resurge waves deposit large amounts of rock fragments in and around the crater. It is common for the crater to almost completely refill and subsequently be buried[.]

Several telescopes livestreamed the entire eclipse, and multiple people caught a glimpse of a small flash of light, seeming to come from around Lagrange crater. Because this event was seen by multiple observers separated by thousands of miles, the only conclusion is that something hit the moon, and its impact event was recorded on video. ...Further investigation will be necessary to determine the size of the meteoroid and obtain pictures of its impact crater, but for a basis of comparison, the LCROSS mission plowed a Centaur upper stage (2.2 tons) into the lunar surface at 2.5 km/s. This should have...

"As it turns out, the eclipse was even more special than most observers had noticed, as the Moon was actually struck by a meteorite while everyone was gazing in wonder at its rusty appearance. The meteorite itself wasn’t terribly large, and is estimated to have only been around 22 pounds. Still, its impact was large enough to be spotted by observers as well as the automated MIDAS system, and that’s pretty cool." I caught it as well with my own equipment. The impact flash appears at 1:23:04 in my video at about the 8 o'clock position near the edge of...

Gol-e-Zard Cave lies in the shadow of Mount Damavand, which at more than 5,000 metres dominates the landscape of northern Iran. In this cave, stalagmites and stalactites are growing slowly over millennia and preserve in them clues about past climate events. Changes in stalagmite chemistry from this cave have now linked the collapse of the Akkadian Empire to climate changes more than 4,000 years ago... It appears that the empire became increasingly dependent on the productivity of the northern lands and used the grains sourced from this region to feed the army and redistribute the food supplies to key supporters....

To the rhinos and crocodiles of the far north, the day was like any other. They ate, swam and napped, unaware a celestial body was headed their way at 60,000 miles per hour. Suddenly, a wayward comet screamed into the atmosphere, struck Earth and created a bowl a mile deep and 15 miles in diameter.

Portuguese scientists have found a depression on the Atlantic Ocean floor they think may be an impact crater. The roughly circular, 6km-wide hollow has a broad central dome and has been dubbed the "Fried Egg" because of its distinctive shape. It was detected to the south of the Azores Islands during a survey to map the continental shelf. If the Fried Egg was made by a space impactor, the collision probably took place within the past 17 million years... It lies under 2km of water about 150km from the Azores archipelago. The depressed ring sits roughly 110m below the...

It took less than 30,000 years and maybe only thousands, to kill more than 90% of sea creatures and most land species, according to the most precise study ever published about the mass extinction marking the end of the Permian Period. Earth's greatest mass extinction, also known as the "Great Dying," occurred about 252 million years ago. By some estimates, over 90% of sea creatures and most land-dwelling reptiles disappeared. Even usually resilient plants and insects suffered near annihilation... Scientists from China, the USA and Canada combined new high-resolution radiometric dating of seven closely spaced layers of volcanic material from...

President Donald Trump’s outgoing chief of staff Reince Priebus told Breitbart News Satuday SiriusXM host Raheem Kassam that the president’s “amazing” work during his first few months in office includes signing a record number of bills into law. “I could tick of for an entire 10, 20 minutes that facts of what’s he’s accomplished and the amazing amount of work he’s done,” Priebus said. “The amount of bills he’s signed are more than any president in the last 50 years,” Priebus said. Priebus — whose departure from the White House was announced on Friday night — also said that Trump...

Yet another Jovian fireball? On May 26th, amateur astronomers recorded a rare impact flash in Jupiter's north polar region. Jupiter just got beaned for the sixth time (that we know about)! On the evening of May 26th, between 19:24.6 and 19:26.2 Universal Time, Sauveur Pedranghelu, a French amateur from Corsica, detected an impact flash live on video in Jupiter's north polar region. The flash was very brief, lasting only about 0.7 second, and displayed two brightness peaks. A bright dot — about the size of Europa when seen in transit — marked the site of impact at latitude 51° north...

Phobos and Deimos are both small for moons — about 14 and 7.7 miles (22.5 and 12.4 kilometers) wide, respectively — and sort of potato-shaped. Compared to other satellites in the solar system, they look more like asteroids. As a result, astronomers previously hypothesized that these moons were asteroids captured by Mars' gravitational pull. ...previous research suggested that Phobos and Deimos would have relatively irregular orbits. In reality, these moons have nearly circular orbits positioned near the Martian equator. ... huge impact that previous research suggested created the gigantic Borealis basin in the northern lowlands of Mars, which covers two-fifths...

Asteroid Vesta: The 10th Planet? Discovery Brightens Odds of Finding Another Pluto Nemesis: The Million Dollar Question HOUSTON, TEXAS -- Our solar system may have had a fifth terrestrial planet, one that was swallowed up by the Sun. But before it was destroyed, the now missing-in-action world made a mess of things. Space scientists John Chambers and Jack Lissauer of NASA's Ames Research Center hypothesize that along with Mercury, Venus, Earth, and Mars -- the terrestrial, rocky planets -- there was a fifth terrestrial world, likely just outside of Mars's orbit and before the inner asteroid belt. Moreover, Planet V...

Hundreds of events – films, concerts, panels with engineers, scientists and astronauts – about asteroids and how to protect our planet from asteroid impacts.The second annual Asteroid Day happens on June 30, 2016. Asteroid Day is a global awareness campaign to help people learn about asteroids and what we can do to protect our planet from asteroid impacts. You can join the Asteroid Day discussion on Twitter and Facebook. Asteroid Day 2016 will also include hundreds of events – films, concerts, interactive workshops and panels with engineers, scientists and astronauts. Here’s the premise of Asteroid Day, in the words of...

An Empire's Epidemic Scientists Use DNA in Search for Answers to 6th Century Plague By THOMAS H. MAUGH II, Times Staff Writer By the middle of the 6th century, the Emperor Justinian had spread his Byzantine Empire around the rim of the Mediterranean and throughout Europe, laying the groundwork for what he hoped would be a long-lived dynasty. His dreams were shattered when disease-bearing mice from lower Egypt reached the harbor town of Pelusium in AD 540. From there, the devastating disease spread to Alexandria and, by ship, to Constantinople, Justinian's capital, before surging throughout his empire. By the time...

Sun's Movement Through Milky Way Regularly Sends Comets Hurtling, Coinciding With Mass Life ExtinctionsA large body of scientific evidence now exists that support the hypothesis that a major asteroid or comet impact occurred in the Caribbean region at the boundary of the Cretaceous and Tertiary periods in Earth's geologic history. Such an impact is suspected to be responsible for the mass extinction of many floral and faunal species, including the large dinosaurs, that marked the end of the Cretaceous period. (Credit: Art by Don Davis / Courtesy of NASA) ScienceDaily (May 2, 2008) — The sun's movement through the Milky...