Taxonomy term

asteroid

It's an asteroid, no wait, a comet, no wait…

NASA’s Hubble Space Telescope has spied a unique object in the debris-filled asteroid belt between Mars and Jupiter: a pair of asteroids — orbiting tightly around each other — that also show comet-like characteristics, including a bright halo of ice and dust known as a coma and a long tail of dust. The odd object, called 2006 VW139/288P, is the first known binary asteroid that is also classified as a main-belt comet.

12 Jan 2018

Small asteroid spotted circling Earth

Earth has a companion other than the moon, according to scientists at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif., who identified a previously unseen asteroid that circles around our planet as it follows its own orbit around the sun.

20 Sep 2016

What are the odds?: Automated system calculates the likelihood that asteroids will hit Earth

By some estimates, Earth is pelted each year by tens of thousands of asteroids — from souvenir-sized nuggets 10 grams and up to the occasional meters-wide boulder. Spotting larger Earth-bound impactors that could cause serious destruction, while they’re still in space, has been a priority of the planetary science community for years. But many space objects are small enough that they can only be detected days or hours before impact — if at all. In a new study, scientists have tested and automated a new technique called systematic ranging that’s intended to rapidly calculate the probability — from only a handful of observations — that newly discovered asteroids will hit Earth.

26 Jan 2016

Ancient asteroids boiled Earth's oceans

The asteroid that wiped out the remaining dinosaurs — save for the avian variety — 66 million years ago was roughly 10 kilometers wide. Long before that, however, early Earth was bombarded by many larger impactors, which pulverized Earth’s surface time and again. Now, a new study published in Geology suggests that two asteroids, dating to Archean times and estimated to be 50 to 100 kilometers in diameter, released enough energy to boil the oceans and reduce sea level by as much as 100 meters or more.
 
10 Oct 2015

Mineral in Chelyabinsk meteorite reveals past collision

A new analysis of fragments of the Chelyabinsk meteorite — which burst over Chelyabinsk, Russia, in February 2013 — reveals that its parent asteroid collided with another asteroid nearly 300 million years before it struck Earth.

20 Dec 2014

Africa's impact is one that even the dinosaurs would have seen coming

The crater left by the infamous Chicxulub asteroid responsible for finishing off the dinosaurs about 65 million years ago, was more than 19 kilometers deep and 177 kilometers in diameter. Those dimensions correspond to a huge energy release estimated at 100 teratons of TNT, but that’s puny compared to an impact that struck South Africa’s Barberton Greenstone Belt about 3.26 billion years ago. Now, researchers have estimated just how big that massive asteroid was and the catastrophic effect it might have had on Earth and its budding plate tectonic system.

14 Aug 2014

2012: The end of the world or just another year of living in harm's way?

We live on a knife-edge, separated from an ocean of super-heated rock by a wafer-thin and perpetually rupturing crust, swinging our way through a cosmic minefield of lethal debris around a nuclear furnace prone to tantrums. For doomsayers, the end of the Mayan long-count calendar, set against such a backdrop, is a gift. Though Mayan culture never spoke of a cataclysm, Dec. 21, 2012 — the purported last day of a 5,125-year cycle in the Mesoamerican calendar — has been added to an endless list of days when the world has been predicted to end.

24 Jul 2012

Undressing Vesta

Researchers find surprising characteristics of the asteroid

Since last July, NASA's Dawn spacecraft has been orbiting the asteroid Vesta and sending back images and other data to the delight and amazement of researchers. Among other surprising characteristics, Vesta has been shown to be one of the most colorful objects in the solar system.

05 Mar 2012

Highlights of 2010: Definitive statements: a new trend?

“This is the way it was.” Or: “This is what is happening.” Hmmm. Scientists don’t usually make such definitive statements, given that in science, there are almost always caveats. Yet in the last year, such statements have been issued by several large groups of scientists who have come together to support a certain point of view. Are scientists feeling the need to dig in their heels because of public pressures? Or are we actually reaching some consensus?

10 Dec 2010

The impact at El'gygytgyn crater

Moment of impact: As the asteroid hits the ground with a velocity of several tens of kilometers per second, a shock wave is generated that penetrates radially into the ground and compresses the rocks.

Contact/compression stage
Christian Koeberl, University of Vienna

 

 

 

 

 

 

 

 

 

20 Jul 2010

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