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To create some gravity, you could hollow a decent-sized asteroid out...and spin it up like a ring-station, using centrifugal force to create that 0.3g. Then, you could build your city entirely within the spinning asteroid; sure, it'd be dark in there, but the rock would protect people from harmful space radiation. That might have a chance of working if the asteroid was made of solid rock with high tensile strength throughout. The team looked into the composition of our local "flying mountains" and found that most are more or less giant piles of rubble, collections of big and small rocks...

Two billion years ago a meteorite 10km in diameter hit the earth about 100km southwest of Johannesburg, creating an enormous impact crater. This area, near Vredefort in the Free State, is now known as the Vredefort Dome... The meteorite, larger than Table Mountain, caused a thousand-megaton blast of energy. The impact would have vaporised about 70 cubic kilometres of rock - and may have increased the earth's oxygen levels to a degree that made the development of multicellular life possible... The original crater, now eroded away, was probably 250 to 300 kilometres in diameter. It was larger than the Sudbury...

The destructive space rock was somewhere between 12.4 and 15.5 miles wide. The largest asteroid ever to hit Earth, which slammed into the planet around 2 billion years ago, may have been even more massive than scientists previously thought. Based on the size of the Vredefort crater, the enormous impact scar left by the gargantuan space rock in what is now South Africa, researchers recently estimated that the epic impactor could have been around twice as wide as the asteroid that wiped out the nonavian dinosaurs. The Vredefort crater, which is located around 75 miles (120 kilometers) southwest of Johannesburg,...

he two brand new minerals were found inside a single 2.5 ounce (70 gram) slice taken from the 16.5 ton (15 metric tons) El Ali meteorite, which crashed to Earth in 2020. Scientists named the minerals elaliite after the meteor and elkinstantonite after Lindy Elkins-Tanton(opens in new tab), the managing director of the Arizona State University Interplanetary Initiative... The researchers classified El Ali as an Iron IAB complex meteorite, a type made of meteoric iron flecked with tiny chunks of silicates. While investigating the meteorite slice, details of the new minerals caught the scientists' attention. By comparing the minerals with...

video at link................ Scientists have discovered three elusive asteroids lurking in a region of space near the sun often cloaked by solar glare, including one they say has the capacity to deliver planetary devastation. One of the asteroids, 2022 AP7, is roughly 1 mile wide and crosses Earth's orbit trajectory around the sun, rendering it one of the most "hazardous" asteroids discovered in the past eight years, a team of researchers announced Monday. “Our twilight survey is scouring the area within the orbits of Earth and Venus for asteroids," said Scott Sheppard, an astronomer at the Earth and Planets Laboratory...

Some asteroids occupy corners of the sky in which the sun's glare smothers them...Last year, in the hope of finding asteroids cloaked by excessive sunlight, an international team of astronomers co-opted a camera primarily designed to investigate the universe's notoriously elusive dark matter.

In a presentation earlier this month, a team of researchers from The Geological Society of America (GSA)identified nine of what they believe to be the most livable caves on the surface of Mars — spaces large enough that they could give future explorers much-needed protection from the harsh environment of the planet's surface, The New York Times reports. The Red Planet is a hostile place: temperatures can drop to below negative 148 degrees Fahrenheit, the atmosphere is incredibly thin, and there's no ozone layer, which means solar radiation is extreme as well. And that's not to mention the very real...

Europe's Mars Express spacecraft has peered deeper into the subsurface of the Martian moon Phobos than ever before, finding hints of unknown structures that could be clues as to the moon's origin. Mars Express, which is a 19-year-veteran spacecraft in orbit around Mars, came within 51.6 miles (83 kilometers) of Phobos on Sept. 22, 2022 and was able to probe beneath the moon's surface using upgraded software on its MARSIS instrument (Mars Advanced Radar for Subsurface and Ionosphere Sounding). Understanding the interior structure of Phobos could be key in solving the mystery of its origin. A close-up of the Martian...

The famous Arecibo Observatory in Puerto Rico completely collapsed in 2020. Now, scientists going through its final observations offer a major new asteroid report...Using data collected by Arecibo between December 2017 and December 2019, scientists have released the largest radar-based report on near-Earth asteroids ever published. The report, published Sept. 22 in The Planetary Science Journal, includes detailed observations of 191 near-Earth asteroids, including nearly 70 that are deemed "potentially hazardous" — that is, large asteroids with orbits that bring them within 4.65 million miles (7.5 million kilometers) of Earth, or roughly 20 times the average distance between Earth and...

A newly discovered, "potentially hazardous" asteroid almost the size of the world's tallest skyscraper is set to tumble past Earth just in time for Halloween, according to NASA. The asteroid, called 2022 RM4, has an estimated diameter of between 1,083 and 2,428 feet (330 and 740 meters) — just under the height of Dubai's 2,716-foot-tall (828 m) Burj Khalifa, the tallest building in the world. It will zoom past our planet at around 52,500 mph (84,500 km/h), or roughly 68 times the speed of sound. At its closest approach on Nov. 1, the asteroid will come within about 1.43 million...

The Psyche spacecraft was supposed to launch toward its namesake, a bizarre metallic space rock in the main asteroid belt, between August and October of this year. But issues with Psyche's flight software made it impossible to hit that window... Psyche will still launch atop a SpaceX Falcon Heavy rocket from NASA's Kennedy Space Center in Florida, as previously planned. 2022 liftoff would have delivered Psyche to its asteroid target in early 2026. But a 2023 launch requires a different trajectory, pushing the arrival back to August 2029... NASA's Janus smallsat mission, which is designed to study two separate binary...

This imagery from NASA’s Hubble Space Telescope from Oct. 8, 2022, shows the debris blasted from the surface of Dimorphos 285 hours after the asteroid was intentionally impacted by NASA’s DART spacecraft on Sept. 26. The shape of that tail has changed over time. Scientists are continuing to study this material and how it moves in space, in order to better understand the asteroid. Credits: NASA/ESA/STScI/Hubble Analysis of data obtained over the past two weeks by NASA’s Double Asteroid Redirection Test (DART) investigation team shows the spacecraft's kinetic impact with its target asteroid, Dimorphos, successfully altered the asteroid’s orbit. This...

NASA’s DART spacecraft intentionally crashed into Dimorphos, a petite moonlet orbiting the larger asteroid Didymos. Now, a telescope on the ground in Chile has imaged the massive plume created by the impact in the days following the encounter. NASA is still sifting through the data of the collision to determine if the Double Asteroid Redirection Test, or DART, altered Dimorphos’s orbital trajectory around its larger companion... The expanding dust trail from the collision is clearly visible, stretching to the right corner of the image. According to a NOIRLab release, the debris trail stretches about 6000 miles (10,000 kilometers) from the...

After 306 days, DART's mission will come to an end when it slams into a Colosseum-sized asteroid 7 million miles from Earth. VIDEO AT LINK.............. This animation shows what it might look like when DART dives into the Didymos dirt. ESA–ScienceOffice.org In less than 12 hours, NASA's DART spacecraft will be no more. After launching atop a SpaceX Falcon 9 on Nov. 24, 2021, the Double Asteroid Redirection Test probe will make its final death dive into the asteroid Dimorphos on Monday, Sept. 26, colliding with the space rock at about 14,000 miles per hour. We've got all the info...

NASA will use a spacecraft later this month to test a planetary-defense method that could one day save Earth.The Double Asteroid Redirect Test spacecraft, otherwise known as DART, will be used as a battering ram to crash into an asteroid not far from Earth on Sept. 26. The mission is an international collaboration to protect the globe from future asteroid impacts."While the asteroid poses no threat to Earth, this is the world's first test of the kinetic impact technique, using a spacecraft to deflect an asteroid for planetary defense," NASA said Thursday.In November 2021, a SpaceX Falcon 9 rocket launched...

The space agency estimates there are about 25,000 asteroids of at least 140m in diameter near Earth's orbit. While the odds of them crashing into our planet at any given time are minuscule, Congress directed Nasa to find 90 per cent of them by 2020. Scientists have found fewer than half. But for reasons it has not publicly explained, the administration has proposed delaying by two years, until 2028, the launch of an infrared space telescope meant to find those threatening asteroids and sharply cutting its budget for next year. About 500 times a year, researchers identify asteroids of at...

Astronomers may have detected a previously undiscovered "mini-moon" in the solar system: a rocky object orbiting a small asteroid near Jupiter. If the rocky satellite, which is just a little wider than the width of Manhattan, is confirmed to be a proper moon, it would be one of the smallest moons ever spotted. The tiny satellite was discovered by scientists working on NASA's Lucy mission, which is sending a space probe to study some of the Trojan asteroids, two massive groups of space rocks that are located on each side of Jupiter on its orbit around the sun. The Lucy...

[T]he most important asteroid discoveries are now being made in twilight, when astronomers are able to look close to the horizon — and close to the sun — for little-known asteroids that orbit inside the orbits of Earth, Venus and even Mercury. That includes the first asteroid with an orbit interior to Venus and one with the shortest-known orbital period around the sun, both of which have been unearthed in the last two years. It also includes "city-killers," asteroids large enough that if they were to impact Earth, the damage would be severe. DECam and another telescope are making it...

An asteroid the size of a 50-story skyscraper will zoom past Earth Sunday (July 17), making its closest approach to our planet in nearly 100 years. The meaty space rock, dubbed 2022 KY4, will safely miss Earth by about 3.8 million miles (6.1 million kilometers), or more than 16 times the average distance between Earth and the moon, according to NASA. This is considerably farther afield than the asteroid 2022 NF, which came within 56,000 miles (90,000 km) — or about 23% the average distance between Earth and the moon — on July 7. Asteroid 2022 KY4 is about 290...

o radar imager Lance Benner at JPL in Pasadena, asteroid 2017 BQ6 resembles the polygonal dice used in Dungeons and Dragons. But my eyes see something closer to a stepping stone or paver you’d use to build a walkway. However you picture it, this asteroid is more angular than most imaged by radar. It flew harmlessly by Earth on Feb. 7 at 1:36 a.m. EST (6:36 UT) at about 6.6 times the distance between Earth and the moon or some about 1.6 million miles. Based on 2017 BQ6’s brightness, astronomers estimate the hurtling boulder about 660 feet (200 meters) across....