Free Republic

Scientists Have Underestimated The Likelihood Of City-Killing Asteroids Hitting Earth Reuters Irene Klotz, Reuters Apr. 28, 2014, 2:59 PM The chance of a city-killing asteroid striking Earth is higher than scientists previously believed, a non-profit group building an asteroid-hunting telescope said on Tuesday. A global network that listens for nuclear weapons detonations detected 26 asteroids that exploded in Earth's atmosphere from 2000 to 2013, data collected by the Comprehensive Nuclear Test Ban Treaty Organization shows. The explosions include the Feb. 15, 2013, impact over Chelyabinsk, Russia, which left more than 1,000 people injured by flying glass and debris. "There is...

Mega-tsunami theory disputed February 03, 2008 SUPPOSED evidence Australia has been subject to prehistoric tsunamis up to 20m in height over the past 10,000 years could just be the result of Aboriginal occupation, a major conference is set to hear tomorrow. Archaeologists from the Australian National University say the theory about the mega-tsunamis, which has influenced the development of emergency service plans in Western Australia, is not supported by evidence. In 2003 Australian geological researchers suggested prehistoric tsunamis over the past 10,000 years were much larger than those recorded since European settlement, including findings of surges up to 20m in...

This is a follow up posting to Younger Dryas -The Rest of the Story!Guest post by Don J. Easterbrook Dept. of Geology, Western Washington University.The Younger Dryas was a period of rapid cooling in the late Pleistocene 12,800 to 11,500 calendar years ago. It followed closely on the heels of a dramatically abrupt warming that brought the last Ice Age to a close (17,500 calendar years ago), lasted for about 1,300 years, then ended as abruptly as it started. The cause of these remarkably sudden climate changes has puzzled geologists and climatologists for decades and despite much effort to find...

Hour-long hailstorm may have caused 1,000-year freeze, say scientists An hour-long hailstorm from space may have changed the climate of the Earth in 11,000 BC, leading to a freeze lasting more than 1,000 years, scientists say. Published: 8:00AM BST 02 Apr 2010 An hour-long hailstorm from space may have changed the climate of the Earth in 11,000 BC, leading to a freeze lasting more than 1,000 years, scientists say. A comet may well have caused the earth to freeze for over 1,000 years Photo: GETTY The catastrophe, caused by a disintegrating comet, wiped out large numbers of animal species and...

The Dark Ages : Were They Darker Than We Imagined? By Greg Bryant Published in the September 1999 issue of Universe As we approach the end of the Second Millennium, a review of ancient history is not what you would normally expect to read in the pages of Universe. Indeed, except for reflecting on the AD 837 apparition of Halley's Comet (when it should have been as bright as Venus and would have moved through 60 degrees of sky in one day as it passed just 0.03 AU from Earth - three times closer than Hyakutake in 1996), you may...

CLIMATE SCIENCEAncient Drought And Rapid Cooling Drastically Altered Climate File image. by Staff Writers Columbus OH (SPX) Jun 23, 2009 Two abrupt and drastic climate events, 700 years apart and more than 45 centuries ago, are teasing scientists who are now trying to use ancient records to predict future world climate. The events - one, a massive, long-lived drought believed to have dried large portions of Africa and Asia, and the other, a rapid cooling that accelerated the growth of tropical glaciers - left signals in ice cores and other geologic records from around the world. Lonnie Thompson, University Distinguished...

It’s a disaster scenario that Hollywood has picked up on (think Deep Impact). An incoming object menaces the Earth. Scientists try to destroy it with nuclear weapons, but the horrified populace soon discovers that the blast has simply broken the object into pieces, each with the potential to wreak havoc planet-wide. Now we learn that an impact between two asteroids causing a similar crack-up may have resulted in the cataclysmic event some 65 million years ago that destroyed the dinosaurs. Researchers from Southwest Research Institute and Charles University (Prague) have been studying the asteroid (298) Baptistina, combining their observations with...

A team of scientists claims to have found the first-ever definitive evidence of a comet striking Earth. After conducting a series of analyses, the researchers determined that a mysterious black pebble discovered years ago in the Egyptian desert is a piece of a comet nucleus — the first ever discovered. "It’s a typical scientific euphoria when you eliminate all other options and come to the realization of what it must be," study lead author Jan Kramers, of the University of Johannesburg in South Africa, said in a statement. [Best Close Encounters of the Comet Kind] The pebble, which the team...

Reference Paulsen, D.E., Li, H.-C. and Ku, T.-L. 2003. Climate variability in central China over the last 1270 years revealed by high-resolution stalagmite records. Quaternary Science Reviews 22: 691-701. What was done In the words of the authors, "high-resolution records of ð13C and ð18O in stalagmite SF-1 from Buddha Cave [33°40'N, 109°05'E] are used to infer changes in climate in central China for the last 1270 years in terms of warmer, colder, wetter and drier conditions." What was learned Among the climatic episodes evident in the authors' data were "those corresponding to the Medieval Warm Period, Little Ice Age and...

Mesopotamian climate change Geoscientists are increasingly exploring an interesting trend: Climate change has been affecting human society for thousands of years. At the American Geophysical Union annual meeting in December, one archaeologist presented research that suggests that climate change affected the way cultures developed and collapsed in the cradle of civilization — ancient Mesopotamia — more than 8,000 years ago. Archaeologists have found evidence for a mass migration from the more temperate northern Mesopotamia to the arid southern region around 6400 B.C. For the previous 1,000 years, people had been cultivating the arable land in northern Mesopotamia, using natural rainwater...

The mysterious fall of the largest of the world's earliest urban civilizations nearly 4,000 years ago in what is now India, Pakistan, Nepal and Bangladesh now appears to have a key culprit — ancient climate change, researchers say. Ancient Egypt and Mesopotamia may be the best known of the first great urban cultures, but the largest was the Indus or Harappan civilization. This culture once extended over more than 386,000 square miles (1 million square kilometers) across the plains of the Indus River from the Arabian Seato the Ganges, and at its peak may have accounted for 10 percent of...

Enlarge ImageThe vault. The sediments at the bottom of the lake in Northen Quebec's Pingualuit Crater hold unmatched clues to North America's climate record.Credit: Robert Fréchette / ARK; (inset) University of Arkansas SAN FRANCISCO, CALIFORNIA--A million years ago, a large meteorite smashed into what is now northern Quebec and created a crater that may become an unprecedented repository of data with which to study long-term climate change, researchers reported here this week at a meeting of the American Geophysical Union. Canada and the northern United States are dotted with tens of thousands of lakes, most of them formed by...

People living in southern Germany during Roman times may have witnessed a comet impact 5,000 times more destructive than the Hiroshima atom bomb, researchers say. Scientists believe a field of craters around Lake Chiemsee, in south-east Bavaria, was caused by fragments of a huge comet that broke up in the Earth’s atmosphere. Celtic artefacts found at the site, including a number of coins, appear to have been strongly heated on one side. This discovery, together with evidence from ancient tree rings and Roman reports of “stones falling from the sky”, has led researchers to conclude that the impact happened in...

British scientists have deciphered a mysterious ancient clay tablet and believe they have solved a riddle over a giant asteroid impact more than 5,000 years ago. Geologists have long puzzled over the shape of the land close to the town of Köfels in the Austrian Alps, but were unable to prove it had been caused by an asteroid. Now researchers say their translation of symbols on a star map from an ancient civilisation includes notes on a mile-wide asteroid that later hit Earth - which could have caused tens of thousands of deaths. The circular clay tablet was discovered 150...

Pravda.RU:Top Stories:More in detail 15:33 2003-03-18Very Large Meteorite Fell Down in Siberia The falling of the meteorite is still mysterious. Scientists say that it might weigh 60 tons The night was rather dull in the north-east of the Russian Irkutsk region on September 25, 2002. All of a sudden, night turned into day. A very bright glow covered the sky, it was hard to look at it. Those people, who happened to be outside at 2 a.m., saw a ball of fire that was flying very fast across the sky. Weird rusting sounds could be heard. A few seconds...

This page presents a summary narrative of and links to geological and paleoclimatalogical data bearing on the remarkable events of 3000 BCE (calendar years BC), when urban/technological society began. Most of ouromes from referenced scientific literature, although some of the studies, such as of the Mesopotamian delta,and certain sea level interpretations, are the author's. You will also find a handy chronological index HERE. A summary graph of events around 3200 BC will be found here.

Crater From 1908 Russian Space Impact Found, Team Says Maria Cristina Valsecchi in Rome, Italy for National Geographic NewsNovember 7, 2007 Almost a century after a mysterious explosion in Russia flattened a huge swath of Siberian forest, scientists have found what they believe is a crater made by the cosmic object that made the blast. The crater was discovered under a lake near the Podkamennaya Tunguska River in western Siberia, where the cataclysm, known as the Tunguska event, took place (see map). On June 30, 1908, a ball of fire exploded about 6 miles (10 kilometers) above the ground in...

...the fall of the great Egyptian Old Kingdom may have been helped along by a common problem which remains with us now -- drought... a severe period of drought around 4,200 years ago may have contributed to the demise of the civilisation. Using seismic investigations with sound waves, along with carbon dating of a 100-metre section of sediment from the bed of Lake Tana in Ethiopia, the team were able to look back many thousands of years. They were able to see how water levels in the lake had varied over the past 17,000 years, with the sediment signalling lush...

**Update -- Intel Hub -- RSOE EDIS is reporting that a 1,000 strong search team was tasked with finding the impact area and so far have been unable to locate it... Such a colossal event, so little media coverage. Around 3:10PM Sunday afternoon residents of Colombia were awestruck when the clear sky was cracked open by a massive fireball that exploded upon impact leaving a 300 foot wide crater and a lot of rattled nerves.

Central Mexico’s Lake Cuitzeo contains melted rock formations and nanodiamonds that suggest a comet impacted Earth around 12,900 years ago, scientists say. CREDIT: Israde et al. (2012) New evidence supports the idea that a huge space rock collided with our planet about 13,000 years ago and broke up in Earth's atmosphere, a new study suggests. This impact would have been powerful enough to melt the ground, and could have killed off many large mammals and humans. It may even have set off a period of unusual cold called the Younger Dryas that began at that time, researchers say. The...