Sentences with phrase «than the asteroids in»

With only a few exceptions, TNOs are larger than the asteroids in the inner solar system.

Not exact matches

And yet Ceres — the largest object in the asteroid belt — is less than one - tenth of a percent the size of Earth and less than 2 % the size of the moon:

Metzger points out that there are far more asteroids near Earth than could ever be explored solely through scientific funding, and highlights the role terrestrial mining operations have played in expanding geologic knowledge.

However, the Rosina mass spectrometer aboard Rosetta found that the ratio of deuterium to hydrogen in the comet is far greater than that found on Earth, adding to the growing body of evidence that the water on Earth was delivered not by comets, as previously thought, but by asteroids.

The meteorite, dubbed Northwest Africa (NWA) 7034, contains a concentration of water by weight about ten times higher than in any of the other 100 or so known Martian meteorites — those rare rocks that get ejected from the Martian surface into space when an asteroid hits the planet, and eventually find their way to Earth.

NASA's Spaceguard survey program, established in 1998, aims to locate and follow at least 90 percent of the estimated 1,100 asteroids that come within about 30 million miles of Earth's orbit around the sun and that are larger than two - thirds of a mile wide.

The particles of rock and ice in these belts vary in size from the tiniest dust grain, smaller than a millimetre across, up to asteroid - like bodies many kilometres in diameter [2].

«I don't think this particular asteroid is more hazardous than others in the MPC list,» he says.

But it is not clear how common ice might be in the main asteroid belt, because sunlight is expected to quickly vaporise ice on the surfaces of airless bodies that fly closer to the sun than Jupiter.

Astronomers say that incoming asteroids smaller than that would have a regional, rather than global, effect; ones that are less than about 180 feet are likely to disintegrate in the atmosphere.

By 2005, lawmakers in Washington asked NASA what it would take to be able to spot 90 percent of near - Earth asteroids more than 460 feet in diameter by 2020.

In all, more than 10 missions have been sent to study asteroids over the years.

Now, a global campaign to map Earth's ancient mega-eruptions, paired with advances in rock dating, is pushing us closer than ever to explaining why some volcanoes and asteroids kill and others don't.

NASA researchers have their own plan, the Near - Earth Object Program — the agency's program to spot 90 percent of all potentially hazardous asteroids more than two - thirds of a mile wide that might hit Earth in the foreseeable future.

Nonetheless, in 2029 the asteroid, dubbed Apophis — derived from the Egyptian god Apep, the destroyer who dwells in eternal darkness — will zoom closer to Earth than the world's communications satellites do.

Furthermore, the team were able to calculate that the food supply in the ocean was fully restored around 1.7 m years after the asteroid strike, which is almost half the original estimates, showing that marine food chains bounced back quicker than originally thought.

June 30: On this date in 1908, more than a century before Russians captured February's meteor on their smartphones, eyewitnesses near Tunguska saw a sky «split in two» and «covered with fire» when an asteroid detonated over Siberia.

If binary asteroids can form single craters, then Earth is more likely to be hit by a pair of objects in future than our planet's crater record would suggest.

But Phobos and Deimos, among the smallest moons in the solar system, look more like misshapen asteroids than Earth's moon, Sumner says.

This technique pinpointed 39 asteroids whose orbits were far more similar than those in any previous family.

Pieces of the asteroid, which seems to have measured no more than 5 metres across, were recently recovered in Sudan.

Space rocks are much more brittle than Earth rocks, suggesting that asteroids on a collision course are more likely to burn up as fireballs in the sky

Among other things, GRACE may have found a crater deep under the Antarctic ice that may mark an asteroid impact greater than the one that doomed the dinosaurs, measured the seafloor displacement that triggered the tsunami of 2004, and quantified changes in subsurface water in the Amazon and Congo river basins.

All families have their rocky patches, but a new family found in our solar system is as rocky as they come: a few dozen asteroids, all born from a parent blasted by an impact less than 6 million years ago.

Although the consequences are roughly comparable in either case, an important difference is that objects in the solar system that circle far away from the sun on long - period orbits before returning, such as comets, would hit the earth at much greater velocities than close - orbiting (short - period) bodies, such as asteroids.

There are many white dwarfs that hold large amounts of hydrogen in their atmospheres, and this new study suggests that this is evidence that water - rich asteroids or comets are common around other stars than the Sun.»

Commenting on the findings lead researcher Dr Roberto Raddi, of the University of Warwick's Astronomy and Astrophysics Group, said: «Our research has found that, rather than being unique, water - rich asteroids similar to those found in our Solar System appear to be frequent.

Scientists estimate that several dozen asteroids in the 20 - to -40-foot (6 - to -12-meter) size range fly by Earth at a distance even closer than the moon every year.

«There are other elements involved, but if size were the only factor, we'd be looking for an asteroid smaller than about 40 feet (12 meters) across,» said Paul Chodas, a senior scientist in the Near - Earth Object Program Office at NASA's Jet Propulsion Laboratory, Pasadena, Calif. «There are hundreds of millions of objects out there in this size range, but they are small and don't reflect a lot of sunlight, so they can be hard to spot.

By examining infrared data taken earlier by the Spitzer Space Telescope, they discovered a swath of dust particles ranging in size from 0.1 to 20 microns (finer than a split hair) that added up to the mass of a large asteroid and, based on their warmth, were strewn about 1.8 Earth — sun distances from the star.

Planned for launch in 2017 or 2018, Lu predicts that Sentinel will find more asteroids in its first month than all previous telescopes combined.

Although astronomer David Jewitt of the Institute for Astronomy in Hawaii thinks Rabinowitz has done a good job counting the big asteroids, he is more worried about the hundreds of thousands of rocks smaller than 1 kilometer but larger than 100 meters.

The first image in the upper left was taken about 9.5 hours before closest approach, when Rosetta was still 510,000 km (315,000 miles) from the asteroid - more distant than the Moon is from the Earth!

The ring system around the icy asteroid Chariklo is the first found encircling anything in our solar system other than a gas giant.

That's up to 9 kilometers per second slower than the average for bigger objects that have hit Earth over its history, says space scientist and asteroid specialist William Bottke of the Southwest Research Institute in Boulder, Colorado.

Of those deportees, about 4 % came from within about 375 million kilometers of the sun, rendering them rock - or metal - rich bodies like asteroids rather than icy orbs like comets, the researchers report online ahead of print in the Monthly Notices of the Royal Astronomical Society.

After circling Vesta for about a year, Dawn will depart for Ceres, which is larger than Vesta, and the only dwarf planet in the Asteroid Belt; it will enter orbit there in 2015.

There may be a million asteroids with masses far greater than ocean liners in Earth - approaching orbits, nearly all of which telescopes have yet to see.

He notes that Congress gave NASA a 2005 mandate to find 90 percent of the near - Earth asteroids more than 140 meters in diameter — big enough to wipe out the Eastern Seaboard or most of California.

There's a slim chance 1950 DA will hit Earth in 2880, and thanks to this finding, we'll know blasting the asteroid apart would be worse than useless: A strike might create multiple jumbles of rocks (held together with van der Waals» forces and gravity) heading our way.

An asteroid, after all, is thought to have wiped out the dinosaurs, and the statistical threat of another strike motivates NASA's Near Earth Object Program, which aims to locate most of the bodies more than 1 kilometer in diameter that swing close to Earth.

But rather than a monotonously uniform surface homogenized by impact cratering over the eons, the first up - close look at the asteroid reveals a full palette of mineral «colors» (mapped here in false color reflecting the wide range of rock compositions).

The researchers have observed 35 asteroid pairs that they think formed in this way, with the offspring less than 60 % of the mass of the parent.

It would orbit faster than Earth and, looking outwards, would see asteroids in Earth - crossing orbits more often than would ground - based instruments.

Marchi's team proposes a novel, more efficient mechanism As the planet was pummeled by primordial asteroids — some larger than 100 kilometers in diameter — impacts would melt large volumes of rock, creating temporary lakes of lava.

Going from a meteoritic sample less than a centimeter in diameter to an asteroid up to a kilometer or more in diameter involves a pretty big leap.

Land - based impacts were, on average, an order of magnitude more dangerous than asteroids that landed in oceans.

His journey through graduate school took longer than usual because he taught at several universities, traveled quite a bit and undertook extensive research in astrophysics, looking in particular at how the composition of asteroids and meteoritic fragments affects their size.

In 1999, the NEAR spacecraft showed that a single asteroid, Eros, contains more gold than has ever been mined on Earth.

Astronomers estimate that we have seen just 1 per cent of the asteroids larger than the one that leveled the forests of Tunguska, Siberia in 1908 — half a million are still out there, unseen.