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On the morning of 30 June 1908, a large explosion occurred near the Podkamennaya Tunguska River in Yeniseysk Governorate (now Krasnoyarsk Krai), Russia. That event is known as the Tunguska event that leveled trees across more than 2,000 square kilometers. It is classified as an impact event, even though no impact crater has been found. Due to the remoteness of the site and the limited instrumentation available at the time of the event, modern scientific interpretations of its cause and magnitude have relied chiefly on damage assessments, and geological studies conducted many years after the fact. The most likely cause...

An international team of researchers from University College Dublin (UCD) and University of Saskatchewan, Canada, have observed 'proton-hopping' movement in a high-pressure form of ice (Ice VII lattices). Ordinary water ice is known as Ice I, while Ice VII is a cubic crystalline form of ice which can be formed from liquid water above 3 GPa (30,000 atmospheres) by lowering its temperature to room temperature, or by decompressing heavy water (D2O) Ice VI below 95 K. Ice VII has a simple structure of two inter-penetrating, and effectively independent, cubic-ice sub-lattices, and is stable across a wide-ranging region above 2 GPa....

The asteroid that wiped out the dinosaurs around 66 million years ago crashed into Earth at “the deadliest possible angle”, researchers have concluded. The giant impacter struck what is today Mexico’s Yucatán Peninsula at around 60 degrees — maximizing the production of climate-altering greenhouse gases. The global disaster caused by the space rock — which was bigger than Mount Everest — was far worse than once thought, Imperial College London experts said. Previous studies had suggested the asteroid came in at an angle of around 30 degrees, while others concluded that it crashed almost straight down. However, the team’s computer...

Our sun has had close encounters with other stars in the past, and it’s due for a dangerously close one in the not-so-distant future. Every 50,000 years or so, a nomadic star passes near our solar system. Most brush by without incident. But, every once in a while, one comes so close that it gains a prominent place in Earth’s night sky, as well as knocks distant comets loose from their orbits. The most famous of these stellar interlopers is called Scholz’s Star. This small binary star system was discovered in 2013. Its orbital path indicated that, about 70,000 years...

Paleontologists have uncovered the remains of megaraptor that lived 70 million years ago, making it one of the last carnivorous dinosaur to roam the Earth. Discovered in Argentina, the team found vertebrae, ribs and part of what would have been the dinosaur's chest and shoulder girdle. After a further analysis, they determined the creature was approximately 33 feet in length -the largest megaraptor found to date. Unlike the Tyrannosaurus rex, this lethal dinosaur had extremely long, muscular arms with massive claws at the end that were used to attack prey.

The last time this occurred was between 1650 and 1715, during what's known as the Little Ice Age in Earth's Northern Hemisphere... Scientists have known this solar minimum was coming because it's a regular aspect of the sun's cycle. Sunspots were peaking in 2014, with low points beginning in 2019, according to NASA. The sun is also responsible for what's known as space weather, sending particles and cosmic rays streaming across our solar system. The sun's strongly magnetised sunspots release solar flares, which can send X-rays and ultraviolet radiation hurtling toward Earth. Even when the sun is quiet during the...

The location of Earth’s north magnetic pole appears to be controlled from deep within Earth by 2 competing blobs in the magnetic field. One is under Canada, and the other is under Siberia. “The Siberian blob is winning,” according to scientists. You probably know that a compass doesn’t point to true north. Earth’s geographic north pole – and magnetic north pole – were first recognized as two different places in 1831. Until the early 1990s, the magnetic North Pole was known to lie some 1,000 miles south of true north, in Canada. Yet, as scientists realized, the location of magnetic...

A major global cooling event that occurred 4,200 years ago may have led to the evolution of new rice varieties and the spread of rice into both northern and southern Asia, an international team of researchers has found. Rice is one of the most important crops worldwide, a staple for more than half of the global population. It was first cultivated 9,000 years ago in the Yangtze Valley in China and later spread across East, Southeast, and South Asia, followed by the Middle East, Africa, Europe, and the Americas. In the process, rice evolved and adapted to different environments, but...

May 8, 2020May 8, 2020 by Evan GoughA Cool Idea to Catch Up With an Interstellar Visitor Poor, dim-witted humanity. We used to think we were the center of everything. That wasn’t that long ago, and even though we’ve made tremendous advancements in our understanding of our situation here in space, we still have huge blind spots.For one, we’re only now waking up to the reality of interstellar objects passing through our Solar System. In 2017, Oumuamua came for a brief visit, and was confirmed as an interstellar object. It’ll never return, and will spend an eternity travelling through the...

A team of researchers affiliated with multiple institutions in Japan has found evidence of embedded carbon emissions on the moon. In their paper published in the journal Science Advances, the group describes their study of carbon data from the KAGUYA lunar orbiter and what they learned from it. The work involved studying a year and a half of data from the KAGUYA lunar orbiter, focusing specifically on carbon emissions. They found that the moon was emitting more carbon than has been thought, and more than could be accounted for by new carbon additions, such as the solar wind or collisions...

A previously unseen asteroid the size of a truck flew about 4,350 miles (7,000 kilometers) over the Pacific Ocean on Monday, making it one of the closest passes by our planet on record. Astronomers had no notice of asteroid 2020 JJ's existence, as it was discovered using the Mt. Lemmon Survey in Arizona right around the time it reached its closest point to us. Had 2020 JJ actually struck Earth, most of it probably would have burned up in the atmosphere. In other words, this space rock wasn't any sort of existential threat, but it did fly closer than many...

Mostafa Waziri, secretary general of the Supreme Council of Antiquities, announced that the newly discovered chamber contained four wooden coffins in poor state of preservation. Dr Ramadan Badri Hussein, archaeological supervisor at the Ministry of State for Antiquities Affairs, said that one of the coffins belongs to a woman called Didibastett. She was buried with six canopic jars, which contradicts with the custom in ancient Egypt which was to embalm the lungs, stomach, intestines and liver of the deceased, and then to store them in four jars under the protection of four gods, known as the Four Sons of Horus......

The extent to which solar activity...varies can be reconstructed using various methods — at least for a certain period of time. Since 1610, for example, there have been reliable records of sunspots covering the Sun; the distribution of radioactive varieties of carbon and beryllium in tree rings and ice cores allows us to draw conclusions about the level of solar activity over the past 9000 years. For this period of time, scientists find regularly recurring fluctuations of comparable strength as during recent decades. A comprehensive catalog containing the rotation periods of thousands of stars has been available only for the...

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...

Slooh will broadcast live telescope views of the near-Earth asteroid, called 1998 OR2, tonight (April 28) beginning at 7 p.m. EDT (2300 GMT). You can watch it live here on Space.com, courtesy of Slooh, or directly from Slooh.com and its YouTube page. This webcast will be free for anyone to watch, but paid members of Slooh can also tune in at Slooh.com and join a so-called "star party" on Zoom, where viewers will be able to join the discussion. Slooh astronomers will also be answering members' questions during this "star party." The one-hour public event will commence just 11 hours...

The interstellar object (alternatively a comet or an asteroid) that killed the dinosaurs when it slammed into Earth didn't work alone. Researchers have shown previously that its after-effects, such as tidal waves and earthquakes, played an important role in the mass extinctions of three-fourths of plant and animal life. Now, new research suggests that one of the most important factors was the soot-rich smoke from fires sparked by the collision. Clay Tabor, a geoscientist at the University of Connecticut, and his colleagues studied soot, sulfates and dust to see how each type of particle may have contributed to the cataclysm....

Deep beneath the North Sea, scientists have discovered a fossilized forest that could hold traces of prehistoric early humans who lived there around 10,000 years ago, before the land slipped beneath the waves a few thousand years later. The discovery gives the researchers new hope in their search for "lost" Middle Stone Age — or Mesolithic — settlements of hunter-gatherers, because the find shows that they have found a particular type of exposed ancient landscape.

The asteroid is called 52768 (1998 OR2), and it was first spotted in 1998. On April 29, it will pass within 3,908,791 miles of Earth, moving at 19,461 miles per hour. That's still 16 times farther than the distance between Earth and the moon. The flyby is expected to occur on Wednesday, April 29, at 5:56 a.m. ET, according to NASA's Center for Near-Earth Object Studies. The center tracks Near-Earth Objects, or NEOs, that could collide with Earth. Arecibo Observatory is a National Science Foundation facility managed by the University of Central Florida. A team of experts has been monitoring...

The new research provides the first quantitative synthesis of faulting across the entire continent, as well as hundreds of measurements of compressive stress directions—the direction from which the greatest pressure occurs in the Earth's crust. The map was produced by compiling new and previously published measurements from boreholes as well as inferences about kinds or "styles" of faults based on earthquakes that have occurred in the past. The three possible styles of faulting include extensional, or normal faulting, in which the crust extends horizontally; strike-slip faulting, in which the Earth slides past itself, like in the San Andreas fault; and...

Earth's last Glacial Maximum period began around 33,000 years ago, when vast ice sheets covered much of the Northern Hemisphere. At the time, the Eurasian ice sheet -- which covered much of Scandinavia -- contained approximately three times the amount of frozen water held in the modern-day Greenland ice sheet. But rapid regional warming saw the ice sheet collapse over a period of just 500 years, according to authors of the study published in Nature Geoscience. Analysing sediment drill cores from the Norwegian Sea, the team found that the ice sheet's collapse contributed to an event known as Meltwater 1A...