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The South Pole of the Moon. (NASA GSFC Scientific Visualisation Studio) =========================================================================== A distant asteroid trailing in the gravitational wake of Mars has been observed in greater detail than ever before, and the close-up reveals a surprising resemblance – one that raises some interesting questions about the object's ancient origins. The asteroid in question, called (101429) 1998 VF31, is part of a group of trojan asteroids sharing the orbit of Mars. Trojans are celestial bodies that fall into gravitationally balanced regions of space in the vicinity of other planets, located 60 degrees in front of and behind the planet. Most...

This image highlights the bright coma of C/2014 OG392 (PANSTARRS). (Northern Arizona University ======================================================================= Centaurs are rare celestial objects that can combine some of the different features of asteroids and comets. They're basically rocky in nature, like asteroids, but can also throw out clouds of dust and gas as their exteriors vaporize, like comets. When centaurs emit these gases, they're considered active. We've only ever found 18 chemically active centaurs in the last century or so, but now a new one has been added to the list – and it might be able to tell us more about how these...

Earth’s atmosphere sees several thousand meteors of fireball magnitude each day, so they are quite common. We are just typically unable to see them due to daylight and because a vast majority occur over oceans and uninhabited regions. However, the brighter the fireball, the more rare it is. Do fireballs make a sound? Sounds like sociology’s favorite question of “If a tree falls in the forest and no one is around to hear it, does it make a noise?” But the answer is quite interesting. According to the American Meteor Society, fireballs can make a sound—two in fact. Both generated...

The massive space rock, known as 2020 UX3, is estimated to have a diameter between 88 and 196 feet, according to NASA's Center for Near Earth Studies (CNEOS). For comparison purposes, the wingspan of a 747 is 225 feet long. It will come within 3.2 million miles of Earth, traveling at roughly 36,000 miles per hour. Its size and its proximity to Earth make it a near-Earth object (NEO). NASA unveiled a 20-page plan in 2018 that details the steps the U.S. should take to be better prepared for NEOs, such as asteroids and comets that come within 30 million...

Centaurs are minor planets thought to have originated in the outer region of our Solar System known as the Kuiper Belt. Active centaurs enigmatically display prominent comet-like features such as comae or tails even though they orbit in the gas giant region where it is too cold for water to readily sublimate. Only 18 active centaurs have been identified since 1927 and, consequently, the underlying activity mechanisms are still poorly understood. 2014 OG392 orbits between 10 and 15 AU (astronomical units) where its equilibrium temperature would be around minus 213 degrees Celsius (minus 351 degrees Fahrenheit). Chandler and colleagues initially...

Only a small handful of objects are known to pose a serious threat to Earth, and the gigantic asteroid Apophis is one of them. Scientists are now re-evaluating its potential to strike our planet in 48 years, owing to improved observations of the problematic asteroid. Observations made earlier this year from the Subaru Telescope in Hawai’i are providing astronomers with a better sense of how the Yarkovsky effect is influencing the orbital path of asteroid 99942 Apophis. This effect is like a built-in propulsion system for asteroids, in which trace amounts of leaking radiation can alter an object’s momentum in...

Explanation: What would an erupting volcano on Venus look like? Evidence of currently active volcanoes on Venus was announced earlier this year with the unexplained warmth of regions thought to contain only ancient volcanoes. Although large scale images of Venus have been taken with radar, thick sulfuric acid clouds would inhibit the taking of optical light vistas. Nevertheless, an artist's reconstruction of a Venusian volcano erupting is featured. Volcanoes could play an important role in a life cycle on Venus as they could push chemical foods into the cooler upper atmosphere where hungry microbes might float. Pictured, the plume from...

For more than two decades, astronomers have been systematically tracing mystery sources of high-energy gamma rays to their sources. One, however, remained stubborn - the brightest unidentified source of gamma rays in the Milky Way. It seemed to be coming from a binary system 2,740 light-years away, but only one of the stars could be found. Now, astronomers have solved the mystery and pinned down that second star by searching gamma-ray data obtained between 2008 and 2018. Together, the two stars constitute one of the weirdest binary systems we've ever seen. "The binary star system and the neutron star at...

There is much debate surrounding the age of the Clovis—a prehistoric culture named for stone tools found near Clovis, New Mexico in the early 1930s—who once occupied North America during the end of the last Ice Age. New testing of bones and artifacts show that Clovis tools were made only during a brief, 300-year period from 13,050 to 12,750 years ago.

A team of geologists at the University of Houston College of Natural Sciences and Mathematics believes they have found the lost plate in northern Canada by using existing mantle tomography images—similar to a CT scan of the earth's interior. The findings, published in Geological Society of America Bulletin, could help geologists better predict volcanic hazards as well as mineral and hydrocarbon deposits. "Volcanoes form at plate boundaries, and the more plates you have, the more volcanoes you have," said Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences. "Volcanoes also affect climate change. So, when...

They used clay tablets to keep records of state treaties and decrees, prayers, myths, and summoning rituals, using a language that researchers were only able to decipher around 100 years ago. Now, the Hittites' texts, which were written in cuneiform, are being made fully accessible online. The collection will be based on around 30,000 documents, most of which are written in the Hittite language, but other languages such as Luwian and Palaic will also be represented to a lesser extent. Participating in the joint project are researchers from the universities of Mainz, Marburg, and Würzburg, as well as of the...

In central Africa is a deep lake that has a dangerous propensity to explode – but tapping it as a source of energy could help avert disaster. Lake Kivu is one of Africa’s strangest bodies of water. An unusual set of properties make it an intriguing subject for scientists, as well as a potential source of both peril and prosperity for the millions of people living nearby. Kivu doesn’t behave like most deep lakes. Typically, when water at the surface of a lake is cooled – by winter air temperatures or rivers carrying spring snowmelt, for example – that cold,...

In what has been called a once-in-a-generation event, a complete and original copy of Shakespeare’s First Folio sold for a record-setting price just under $10 million at auction earlier this week. The First Folio, published in 1623, was the first complete printed collection of Shakespeare’s plays. Published seven years after the author’s death, the book marked not only the first complete collection of Shakespeare’s works, but also the first time those works were organized as comedies, tragedies and histories. There are around 235 copies known to exist, and only six complete ones owned privately.

Grímsvötn volcano on Iceland produced an unusually large and powerful eruption in 2011, sending ash 20 kilometres into the atmosphere, causing the cancellation of about 900 passenger flights. In comparison, the much smaller 2010 eruption of Eyjafjallajökull led to the cancellation of about 100,000 flights. Grímsvötn is a peculiar volcano, as it lies almost wholly beneath ice, and the only permanently visible part is an old ridge on its south side which forms the edge of a large crater (a caldera). And it is along the base of this ridge, under the ice, that most recent eruptions have occurred. Another...

232 waterspouts/funnels have been confirmed over the Great Lakes from September 28 to October 4, 2020, in the second world record waterspout outbreak of the year, according to the International Center for Waterspout Research (ICWR). From August 16 to 19, 2020, a short-lived waterspout outbreak produced 88 funnels, setting a new world record waterspout outbreak -- the first of the year. Both outbreaks were a result of Canadian cold air sweeping over the region, which made surface air prone to rise. "There were an average of 33 per day," said ICWR director Wade Szilagyi, also a meteorologist at Environment Canada....

In just a few days, NASA is going to bounce its probe OSIRIS-REx off asteroid Bennu. The mission will collect a sample from the asteroid, and return it to Earth for closer study - one of the first missions of its kind. That return sample will help us to understand not just asteroids, but the earliest days of the Solar System's existence. However, that is not the sole mission of OSIRIS-REx. The probe arrived in Bennu orbit in December of 2018, and since that time has been using its suite of instruments to learn as much as it can about...

A rare phenomenon formed in Abkhazia, on the eastern coast of the Black Sea, on September 23, 2020. According to local and tourist eyewitnesses, the water started twisting into a gigantic spiral. The whirlpool most probably formed by the collision of water masses having different characteristics (salinity, temperature, etc.).

Impact craters have been called the “poor geologists’ drill,” since they allow scientists to look beneath to the subsurface of a planet without actually digging down. It’s estimated that Mars has over 600,000 craters, so there’s plenty of opportunity to peer into the Red Planet’s strata – especially with the incredible HiRISE (High Resolution Imaging Science Experiment) camera on board the Mars Reconnaissance Orbiter which has been orbiting and studying Mars from above since 2006. This beautiful image shows the interior of an impact crater in the Hellas Planitia region of Mars – just north of the gigantic Hellas impact...

In its 4.5 billion year history, Earth has had to run the gauntlet. Numerous catastrophes have imperilled the planet, from massive impacts, to volcanic conflagrations, to frigid episodes of snowball Earth. Yet life persists. Among all of the hazards that threaten a planet, the most potentially calamitous might be a nearby star exploding as a supernova. When a massive enough star reaches the end of its life, it explodes as a supernova (SN). The hyper-energetic explosion can light up the sky for months, turning night into day for any planets close enough. If a planet is too close, it will...

This one is a video, at link. Explanation: Does the Sun change as it rotates? Yes, and the changes can vary from subtle to dramatic. In the featured time-lapse sequences, our Sun -- as imaged by NASA's Solar Dynamics Observatory -- is shown rotating though an entire month in 2014. In the large image on the left, the solar chromosphere is depicted in ultraviolet light, while the smaller and lighter image to its upper right simultaneously shows the more familiar solar photosphere in visible light. The rest of the inset six Sun images highlight X-ray emission by relatively rare iron...