It ain’t gravity holding this asteroid together
Astronomers have discovered that near Earth asteroid 1950DA is spinning so fast that gravity can’t hold it together. Instead, it is kept whole by cohesive forces called van der Waals forces, predicted but never detected before on an asteroid.
This is the coolest factoid from the article, however:
“We found that 1950 DA is rotating faster than the breakup limit for its density,” said Rozitis. “So if just gravity were holding this rubble pile together, as is generally assumed, it would fly apart. Therefore, interparticle cohesive forces must be holding it together.”
In fact, the rotation is so fast that at its equator, 1950 DA effectively experiences negative gravity. If an astronaut were to attempt to stand on this surface, he or she would fly off into space unless he or she were somehow anchored.
The important take away from this discovery is that it will be very easy to break this kind of asteroid up, turning a large and big threat into a collection of small but harmless rocks.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Astronomers have discovered that near Earth asteroid 1950DA is spinning so fast that gravity can’t hold it together. Instead, it is kept whole by cohesive forces called van der Waals forces, predicted but never detected before on an asteroid.
This is the coolest factoid from the article, however:
“We found that 1950 DA is rotating faster than the breakup limit for its density,” said Rozitis. “So if just gravity were holding this rubble pile together, as is generally assumed, it would fly apart. Therefore, interparticle cohesive forces must be holding it together.”
In fact, the rotation is so fast that at its equator, 1950 DA effectively experiences negative gravity. If an astronaut were to attempt to stand on this surface, he or she would fly off into space unless he or she were somehow anchored.
The important take away from this discovery is that it will be very easy to break this kind of asteroid up, turning a large and big threat into a collection of small but harmless rocks.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
This is just a random, curious thought with no evidence behind it. I wonder if this mysterious effect also applies on the galactic and intergalactic scales, and if so, could it be the explanation for dark matter — which so far has eluded all efforts at detection? Probably not, but there might be other, as yet unknown forces that govern the structure of the galaxies and their movement within the cosmos. As Robert often comments: the uncertainty of science.