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Smaller asteroids may pose greater danger than previously believed INCINERATION POSSIBLE - Fine points of the "fireball" that might be expected from an asteroid exploding in Earth's atmosphere are indicated in a supercomputer simulation devised by a team led by Sandia researcher Mark Boslough. (Photo by Randy Montoya ) Download 300dpi JPEG image (Media are welcome to download/publish this image with related news stories.)ALBUQUERQUE, N.M. — The stunning amount of forest devastation at Tunguska a century ago in Siberia may have been caused by an asteroid only a fraction as large as previously published estimates, Sandia National Laboratories supercomputer simulations...

'Asteroid impact could have prompted Constantine's conversion' An asteroid which exploded like a nuclear bomb may have converted the Roman emperor Constantine to Christianity it is now being claimed. Scientists have discovered an impact crater dating from the fourth of fifth century in the Italian Apennine mountains. They believe the crater in the Sirente mountains, which is larger than a football field, could explain the legend of Constantine's conversion. Accounts from the 4th century describe how barbarians stood at the gates of the Roman empire while a Christian movement threatened its stability from within. It is said the emperor saw...

Startling evidence has been found which shows mammoth and other great beasts from the last ice age were blasted with material that came from space.Eight tusks dating to some 35,000 years ago all show signs of having being peppered with meteorite fragments. The ancient remains come from Alaska, but researchers also have a Siberian bison skull with the same pockmarks. The scientists released details of the discovery at a meeting of the American Geophysical Union in San Francisco, US. They painted a picture of a calamitous event over North America that may have severely knocked back the populations of some...

In late June of 1908, a fireball exploded above the remote Russian forests of Tunguska, Siberia, flattening more than 800 square miles of trees. Researchers think a meteor was responsible for the devastation, but neither its fragments nor any impact craters have been discovered. Astronomers have been left to guess whether the object was an asteroid or a comet, and figuring out what it was would allow better modeling of potential future calamities. Italian researchers now think they've found a smoking gun: The 164-foot-deep Lake Cheko, located just 5 miles northwest of the epicenter of destruction. "When we looked at...

By Deborah Zabarenko WASHINGTON (Reuters) - Even small asteroids that never hit Earth could have deadly consequences, because they might be mistaken for nuclear blasts by nations that lack the equipment to tell the difference, scientists said on Thursday. One such asteroid event occurred June 6, when U.S. early warning satellites detected a flash over the Mediterranean that indicated an energy release comparable to the atomic bomb dropped on Hiroshima, U.S. Brig. Gen. Simon Worden told a congressional hearing. The flash occurred when an asteroid perhaps 10 yards in diameter slammed into Earth's atmosphere, producing a shock wave that would...

The so-called ‘Tunguska Event’ refers to a major explosion that occurred on 30 June 1908 in the Tunguska region of Siberia, causing the destruction of over 2000 km2 of taiga, globally detected pressure and seismic waves, and bright luminescence in the night skies of Europe and Central Asia, combined with other unusual phenomena. The ‘Tunguska Event’ may be related to the impact with the Earth of a cosmic body that exploded about 5–10 km above ground, releasing in the atmosphere 10–15 Mton of energy. Fragments of the impacting body have never been found, and its nature (comet or asteroid) is...

On the morning of June 30, 1908, the sky exploded over a remote region of central Siberia. A fireball powerful as hundreds of Hiroshima atomic blasts scorched through the upper atmosphere "as if there was a second sun," according to one eyewitness. Scientists today think a small fragment of a comet or asteroid caused the "Tunguska event," so named for the Tunguska river nearby. No one knows for certain, however, because no fragment of the meteoroid has ever been found. The explosion was so vast—flattening and incinerating over an 800 square-mile swath of trees—that generations of amateur sleuths have put...

HOW - 1. "actually you will not be able to see it ... " Spotting ToutatisToutatis will not be visible to the unaided eye. Experienced telescope users can see it now from the Southern Hemisphere, and in early October it will be visible from the north. Finding Toutatis will be challenging, Harris said, due to a combination of the asteroid's position in the sky and interfering moonlight. Because the asteroid is so close, its location in the sky will vary significantly for skywatchers in different places on Earth at any given moment. And because it moves quickly, the location changes...

Rather than look for the light reflected directly by these objects (as is customary astronomy practice), this project will search for those very rare moments when one of these objects passes between the telescopes and a nearby background star. This brief "eclipse" lasts less than a second, but will allow the scientists to study objects that are much too faint to be seen in reflected sunlight, even with the largest telescopes.

Comet C/2017 K2 will be at its closest point to us for the next few million years this week. Hubble caught sight of comet K2 when it was out between the orbits of Saturn and Uranus. NASA, ESA, and A. Feild (STScI) One of the largest comets known is about to zip by our planet on the only trip through the inner solar system it will make during our lifetimes. Five years ago, the Hubble Space Telescope spotted a large comet at the farthest distance ever, as it was approaching the sun from way out between the orbits of Saturn...

In a new study, researchers analyzed some of the tiny fragments of space rock that were left behind after the meteor exploded, known as meteorite dust. Normally, meteors produce a small amount of dust as they burn up, but the tiny grains are lost to scientists because they are either too small to find, scattered by the wind, fall into water or are contaminated by the environment. However, after the Chelyabinsk meteor exploded, a massive plume of dust hung in the atmosphere for more than four days before eventually raining down on Earth's surface, according to NASA. And luckily, layers...

You can see it now, and the view could be getting better in the next two weeks. The comet is called Comet C/2017 K2 and was discovered using the telescope called PanSTARRS. The comet was spotted just five years ago in May 2017... C/2017 K2 is heading toward the sun, and coming closer to Earth. The comet will make its closest approach to Earth on July 14. The comet can now be seen with binoculars in the southern sky after dark. The best viewing is done out in the countryside, away from city lights. NASA adds that C/2017 K2, “is...

Over 100 participants from 18 countries – including NASA scientists and the agency’s NEOWISE mission – took part in the international exercise. Watching the skies for large asteroids that could pose a hazard to the Earth is a global endeavor. So, to test their operational readiness, the international planetary defense community will sometimes use a real asteroid’s close approach as a mock encounter with a “new” potentially hazardous asteroid. The lessons learned could limit, or even prevent, global devastation should the scenario play out for real in the future. To that end, more than 100 astronomers from around the world...

Those meteors could flare up when our planet passes through the pieces of a disintegrating comet called Schwassmann-Wachmann 3 (SW3). It isn't just an exciting opportunity for skywatchers; comet scientists eagerly anticipate the encounter as well. According to NASA, the meteor shower could amaze (or disappoint) overnight on Memorial Day (Monday, May 30) and run into early Tuesday. SW3 is fairly close to the sun by comet standards; it completes an orbit of our star once every five years. In 1995, it started to break apart, shattering into dozens of smaller pieces and leaving behind a cloud of debris that...

There is no need to tell what a comet is.Because on such a great platform most of you may know more than me.As I am just a student with little English.But regardless of that, there is something you may also agree with.That, comet is something interesting. Isn't it?Just think about it: a small chunk of ice or dirt revolving around the sun.Same as the facts that I have here.Interesting facts about comets:1. The first comet was observed long ago around 500 B.C. by a Greek philosophers. 2. Many Scientists think that comets were leftovers from the early development of our...

NASA's Hubble Space Telescope has determined the size of the largest icy comet nucleus ever seen by astronomers. The estimated diameter is approximately 80 miles across, making it larger than the state of Rhode Island. The nucleus is about 50 times larger than found at the heart of most known comets. Its mass is estimated to be a staggering 500 trillion tons, a hundred thousand times greater than the mass of a typical comet found much closer to the Sun. The behemoth comet, C/2014 UN271 (Bernardinelli-Bernstein) is barreling this way at 22,000 miles per hour from the edge of the...

Explanation: Only twenty-five years ago, Comet Hale-Bopp rounded the Sun and offered a dazzling spectacle in planet Earth's night skies. Digitized from the original astrophoto on 35mm color slide film, this classic image of the Great Comet of 1997 was recorded a few days after its perihelion passage on April 1, 1997. Made with a camera and telephoto lens piggy-backed on a small telescope, the 10 minute long, hand-guided exposure features the memorable tails of Hale-Bopp, a whitish dust tail and blue ion tail. Here, the ion tail extends well over ten degrees across the northern sky. In all, Hale-Bopp...

The Yilan crater. (NASA Earth Observatory/Lauren Dauphin/Landsat data/USGS) A crescent-shaped crater in Northeast China holds the record as the largest impact crater on Earth that formed in the last 100,000 years. Prior to 2020, the only other impact crater ever discovered in China was found in Xiuyan county of the coastal province of Liaoning, according to a statement from the NASA Earth Observatory. Then, in July 2021, scientists confirmed that a geological structure in the Lesser Xing'an mountain range had formed as a result of a space rock striking Earth. The team published a description of the newfound impact crater...

Comet Bernardinelli-Bernstein is currently inbound from the Oort Cloud, a distant region of the solar system known for packing billions and possibly trillions of icy objects. The comet will make its closest approach to Earth in 2031, when it will come to within 11 au of the Sun (1 billion miles), in which 1 au is the average distance from Earth to the Sun. The comet, coming no closer than Saturn, won’t likely be visible to the unaided eye, but astronomers will be keeping a close watch, as it’s turning out to be a rather extraordinary object. Named after its...

Researchers from the University of Cincinnati have found evidence of a cosmic cataclysm 1,500 years that may be responsible for the downfall of the Hopewell Culture. The Hopewell Culture was a widely dispersed set of pre-Columbian Native American populations connected by a common network of trade routes from 100 BC to AD 500 in the Middle Woodland period. The researchers found evidence of a cosmic airburst at 11 Hopewell archaeological sites in three states stretching across the Ohio River Valley in the United States, which rained debris down into the Earth’s atmosphere creating a fiery explosion around 1,500 years ago...