Why are the oldest meteorites important

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How viruses shape our world. The era of greyhound racing in the U. In the first known case of an extraterrestrial object to have injured a human being in the U. Instead, it exploded in the air a few miles up. The force of the explosion was powerful enough to knock over trees in a region hundreds of miles wide. Scientists think the meteor itself was about feet 37 meters across and weighed million pounds million kilograms. Locally, hundreds of reindeer were killed, but there was no direct evidence that any person perished in the blast.

More recently, in the world was startled by a brilliant fireball that streaked across the sky above Chelyabinsk, Russia. The house-sized meteoroid entered the atmosphere at over 11 miles 18 kilometers per second and blew apart 14 miles 23 kilometers above the ground. The explosion released the energy equivalent of around , tons of TNT and generated a shock wave that blew out windows over square miles square kilometers and damaged buildings.

More than 1, people were injured in the blast, mostly due to broken glass. The smaller piece in the foreground is called "Lebanon B. Meteor Crater in Arizona. Note vehicles in parking lot for scale. Credit: USGS. Full Moon Guide: October - November Models and lab tests suggest the asteroid could be venting sodium vapor as it orbits close to the Sun, explaining its increase in brightness.

The Perseids are already showing up in our night skies, and they peak in mid-August. The Perseids are on the Rise! The next full Moon will be on Thursday afternoon, Oct. The Moon will appear full from Wednesday morning through Saturday morning. Despite its small size, this space rock is a colossal find. It's one of the best-preserved meteorites of its kind ever found.

Ice-blue clouds are drifting over the Arctic and that means noctilucent cloud season is here. Australian Meteor Crater is the Oldest Known. What's Up for January? The oldest meteorite specimens are remnants of the very first geologic processes to occur in our solar system 4.

The origin of the solar system should not be confused with the origin of the universe, commonly known as the Big Bang, which occurred at least 9 billion years ago and possibly as long ago as 20 billion years. Our solar system formed when a cloud of interstellar dust and gas collapsed. Because the interstellar cloud had been slowly spinning, the result was a nearly flat rotating disk which we refer to as the solar nebula.

Much of the dust and gas in the disk moved to the center of the nebula where it fed a growing protostar which eventually became our sun. A schematic diagram of the collapse of a molecular cloud core to form the solar nebula. There was a critical radius in the outer portion of the nebula beyond which a small amount of material was transported outward short horizontal arrows.

This created a zone with a high density of dust near the midplane. A series of aggregational processes swept up this dust to form planetesimals and eventually planets. A microscopic view of a spherical chondrule, 1 millimeter in diameter. The bright, colored regions within its margins are mineral crystals. The black region between the crystals is glass and represents once-molten material. This chondrule is in Semarkona, an unequilibrated ordinary chondrite which fell in the Madhya Pradesh region of India.