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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...

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...

Like a mushroom shooting out spores, a well-known comet was seen firing multiple "mini comets" that went sailing away at up to 280 miles (451 kilometers) an hour, astronomers have announced. The fragments were recently revealed in high-resolution images of comet Holmes, a relatively small body discovered in 1892 that mysteriously erupted in 2007, when the above images were taken. (Black-ringed dots moving in the images are background stars.) Over several days astronomers using the Canada-France-Hawaii telescope on Mauna Kea watched the 2.2-mile-wide (3.5-kilometer-wide) cloud of dust surrounding the comet swell to become larger than the sun. Later, closer looks...

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.

"Before SOHO was launched, 16 sungrazing comets had been discovered by space observatories. Based on that experience, who could have predicted that SOHO would discover more than sixty times that number, and in only nine years? This is truly a remarkable achievement!" said Dr. Chris St. Cyr, Senior Project Scientist for NASA's Living With a Star program at NASA Goddard Space Flight Center in Greenbelt, Md.

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...

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...

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...

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...

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...

Explanation: This picture was supposed to feature a comet. Specifically, a series of images of the brightest comet of 2021 were being captured: Comet Leonard. But the universe had other plans. Within a fraction of a second, a meteor so bright it could be called a fireball streaked through just below the comet. And the meteor's flash was even more green than the comet's coma. The cause of the meteor's green was likely magnesium evaporating from the meteor's pebble-sized core, while the cause of the comet's green was likely diatomic carbon recently ejected from the comet's city-sized nucleus. The images...

Paris (AFP) - The Solar System has at least two more planets waiting to be discovered beyond the orbit of Pluto, Spanish and British astronomers say. The official list of planets in our star system runs to eight, with gas giant Neptune the outermost. Beyond Neptune, Pluto was relegated to the status of "dwarf planet" by the International Astronomical Union in 2006, although it is still championed by some as the most distant planet from the Sun. In a study published in the latest issue of the British journal Monthly Notices of the Royal Astronomical Society, researchers propose that "at...

This year, the Eta Aquarids meteor shower runs April 19th to May 28th, peaking May 5th just before morning twilight. The Eta Aquarids are visible all across the globe but are more pronounced in the Southern Hemisphere sky. It is there that the Eta Aquarids can produce up to 20 to 40 meteors per hour. In the mid-northern latitudes, the count is closer to 10 meteors per hour. There is an opportunity to see a few meteors late evening (post-sunset on May 4th) as this is when “earthgrazers” are best seen. Earthgrazers tend to be fewer in quantity but are...

Eta Aquarids have a most interesting lineage. Unlike some of the other annual meteor displays whose history can be traced back for many centuries, the Eta Aquarids were not "officially" discovered until the late 19th century. In 1870, while sailing in the Mediterranean Sea, Lt. Col. G.L. Tupman sighted 15 meteors on the morning of April 30, and another 13 a few mornings later. All the meteors Tupman sighted appeared to emanate from the constellation of Aquarius. Then in 1876, professor Alexander Stewart Herschel pointed out that the orbit of Halley’s comet nearly coincided with Earth's orbit around May 4,...

The Early History of humansSince the olden days, humans have looked up in the sky and blamed astronomical events for the unpleasant things happening to them (which was purely a coincidence). Not only this, but humans had also praised the occasions when a good thing happened after a few astronomical sightings (which was also coincidental). I am talking about the events that include sighting a comet, meteor shower or Northern lights, and even novas. In the 15th century, Pope Callixtus III excommunicated comets as an ‘Instrument of the Devil’. In 1835-36, when Halley’s Comet arrived, people assumed that it had...

Explanation: Sweeping through northern predawn skies, on November 24 Comet Leonard (C/2021 A1) was caught between two galaxies in this composite telescopic image. Sporting a greenish coma the comet's dusty tail seems to harpoon the heart of NGC 4631 (top) also known as the Whale Galaxy. Of course NGC 4631 and NGC 4656 (bottom, aka the Hockey Stick) are background galaxies some 25 million light-years away. On that date the comet was about 6 light-minutes from our fair planet. Its closest approach to Earth (and even closer approach to Venus) still to come, Comet Leonard will grow brighter in December....