Category Astronomy/Space

Impact that Killed the Dinosaurs Triggered ‘Mega-Earthquake’ that Lasted Weeks to Months

Deformed spherule-rich layer at Gorgonilla Island (Colombia) showing that seismic activity persisted for weeks or months after impact. Credit: Hermann Bermúdez. Click on the image for a larger version.

66 million years ago, a 10-kilometer asteroid hit Earth, triggering the extinction of the dinosaurs. New evidence suggests that the Chicxulub impact also triggered an earthquake so massive that it shook the planet for weeks to months after the collision. The amount of energy released in this mega-earthquake is estimated at 1023 joules, which is about 50,000 times more energy than was released in the magnitude 9.1 Sumatra earthquake in 2004.

Hermann Bermúdez will present evidence of this “mega-earthquake” at the upcoming GSA Connects meeting in Denver this Sunday, 9 October...

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Astronomers find a ‘Cataclysmic’ Pair of Stars with the Shortest Orbit yet

The huge sun-like star, left, looks like a blue balloon that turns orange as it’s being sucked into the tiny white dwarf’s orbit. The white dwarf looks like a mini-galaxy, with a blue center and orange rings. The background is black with tiny stars.
Caption:An artist’s illustration shows a white dwarf (right) circling a larger, sun-like star (left) in an ultra-short orbit, forming a “cataclysmic” binary system.
Credits:Credit: M.Weiss/Center for Astrophysics | Harvard & Smithsonian

The stars circle each other every 51 minutes, confirming a decades-old prediction. Astronomers have discovered a stellar binary, or pair of stars, with an extremely short orbit, appearing to circle each other every 51 minutes. The system seems to be one of a rare class of binaries known as a ‘cataclysmic variable,’ in which a star similar to our sun orbits tightly around a white dwarf — a hot, dense core of a burned-out star.

A cataclysmic variable occurs when the two stars draw close, over billions of years, causing the white dwarf to start acc...

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Laughing Gas in Space could mean Life
Exoplanet hunters should check for N2O

Nitrous oxide is a constituent of Earth’s atmosphere that provides evidence of life. (NASA/LROC science team)

Scientists at UC Riverside are suggesting something is missing from the typical roster of chemicals that astrobiologists use to search for life on planets around other stars — laughing gas.

Chemical compounds in a planet’s atmosphere that could indicate life, called biosignatures, typically include gases found in abundance in Earth’s atmosphere today.

“There’s been a lot of thought put into oxygen and methane as biosignatures. Fewer researchers have seriously considered nitrous oxide, but we think that may be a mistake,” said Eddie Schwieterman, an astrobiologist in UCR’s Department of Earth and Planetary Sciences.

This conclusion, and the modeling work that led to it,...

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Collision may have Formed the Moon in Mere Hours, Simulations Reveal

A new NASA and Durham University simulation puts forth a different theory of the Moon’s origin – the Moon may have formed in a matter of hours, when material from the Earth and a Mars sized-body were launched directly into orbit after the impact. The simulations used in this research are some of the most detailed of their kind, operating at the highest resolution of any simulation run to study the Moon’s origins or other giant impacts.
Credits: NASA’s Ames Research Center

Most theories claim the Moon formed out of the debris of this collision, coalescing in orbit overa months or years. A new simulation puts forth a different theory — the Moon may have formed immediately, in a matter of hours, when material from the Earth and Theia was launched directly into orbit after the impact.

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