As usual it will miss us. As well, the technology will exist to move it about by then anyway if the threat is significant.
In fact I have seen sufficient evidence of prior movements to have
little doubt that it is possible even if we are restricted to
Newtonian methods.
As well the extreme spin suggests that the object is solid enough for
actual workings.
As usual this is headline silliness.
Human life could be
wiped out on March 16, 2880 because a huge asteroid is hurtling
towards Earth - and experts don't know how to stop it
- Asteroid 1950 DA has a 0.3 per cent chance of hitting Earth in 867 years
- A possible impact date for 1950 DA is on 16 March, 2880, scientists say
- If it hits, it would do so with a force of 44,800 megatonnes of TNT
- But scientists say there is no cause for concern as the risk is low
- Asteroid's body defies gravity due to forces known as van Der Waals
- These forces have never been spotted on an asteroid before
- Scientists say they are now closer to finding out how to stop the rock
By ELLIE
ZOLFAGHARIFARD FOR MAILONLINE
PUBLISHED: 17:11
GMT, 15 August 2014
The asteroid, named
1950 DA, is a rock two-thirds of a mile in diameter, travelling at
about 15 km (nine miles) per second relative to the Earth.
It is approximately
3,280ft (1,000 metres) in diameter, but rotates once every two hours
and six minutes.
At this rate, the rock
should break apart and eventually disintegrate, but it is not showing
any signs of doing so.
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 presence of
cohesive forces has been predicted in small asteroids, but definitive
evidence has never been seen before.
It is due to swing so
close to Earth it could slam into the Atlantic Ocean at 38,000 miles
per hour.
It is estimated that
if 1950 DA were to collide with the planet, it would do so with an
force of around 44,800 megatonnes of TNT.
Although the
probability of an impact is only 0.3 per cent, this represents a risk
50 per cent greater than an impact from all other asteroids
The date of Earth's
potential destruction has been set at 16 March 2880, when an asteroid
hurtling through space has a possibility of striking our planet.
Researchers studying the rock found that its body rotates so quickly,
it should break apart, but somehow remains intact on its Earth-bound
trajectory
The discovery was made
by researchers at the University of Tennessee (UT), Knoxville.
Previous research has
shown that asteroids are loose piles of rubble held together by
gravity and friction.
However, the UT team
found that the asteroid, called 1950 DA, is spinning so quickly that
it defies these forces.
It is approximately
3,280ft (1,000 metres) in diameter, but rotates once every two hours
and six minutes.
At this rate, the rock
should break apart and eventually disintegrate, but it is not showing
any signs of doing so.
Ben Rozitis, a
postdoctoral researcher; Eric MacLennan, a doctoral candidate; and
Joshua Emery, an assistant professor in the Department of Earth and
Planetary Sciences, wanted to know what keeps the body from breaking
apart.
By calculating 1950
DA’s temperature and density, the team detected the cohesive
forces that stop it breaking up.
'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, they would would be flung off
into space.
The presence of
cohesive forces has been predicted in small asteroids, but definitive
evidence has never been seen before.
The findings,
published in this week's edition of the science journal Nature, have
potential implications for defending our planet from a massive
asteroid impact.
'Following the
February 2013 asteroid impact in Chelyabinsk, Russia, there is
renewed interest in figuring out how to deal with the potential
hazard of an asteroid impact,' said Professor Rozitis.
A simulation of an
asteroid impact tsunami developed by scientists at the University of
California, Santa Cruz, shows waves as high as 400 feet sweeping onto
the Atlantic Coast
'Understanding what
holds these asteroids together can inform strategies to guard against
future impacts.'
This research reveals
some techniques, such sending a massive object on a collision course
with the asteroid, could worsen the effects.
For example, this
technique could get in the way of forces keeping the asteroid
together, causing it to break apart into lots of smaller, threatening
asteroids that could be on a collision course for Earth.
This may be what
occurred with the asteroid P/2013 R3, which was caught by the Hubble
Space Telescope in 2013 and 2014 coming undone, possibly due to a
collision with a meteor.
'With such tenuous
cohesive forces holding one of these asteroids together, a very small
impulse may result in a complete disruption,' said Professor Rozitis.
The asteroid is
travelling at about 9 miles (15km) a second relative to the Earth.
It is due to swing so
close to Earth it could slam into the Atlantic Ocean at 38,000 miles
per hour.
It is estimated that
if 1950 DA were to collide with the planet, it would do so with a
force of around 44,800 megatonnes of TNT.
Although the
probability of an impact is only 0.3 per cent, this represents a risk
50 per cent greater than an impact from all other asteroids.
Over the long
timescales of Earth's history, asteroids this size and larger have
periodically hammered the planet.
The so-called K/T
impact, for instance, ended the age of the dinosaurs 65 million years
ago.
Asteroid 1950 DA was
discovered on 23 February 1950. It was observed for 17 days and then
faded from view for half a century.
Then, an object
discovered on 31 December 2000 was recognised as being the long-lost
1950 DA.
The New Year's Eve
sighting was exactly 200 years to the night after the discovery of
the first asteroid, Ceres.
It was found that the
asteroid 1950 DA has a trajectory that for a 20-minute window on
March 16, 2880, a collision cannot be entirely ruled out.
This graphic shows the
orbits of all the known Potentially Hazardous Asteroids (PHAs),
numbering over 1,400 as of early 2013. These are the asteroids
considered hazardous because they are fairly large (at least 460 feet
or 140 meters in size), and because they follow orbits that pass
close to the Earth's orbit
But scientists claim
there is no cause for concern.
If it is eventually
decided 1950 DA needs to be diverted, the hundreds of years of
warning could allow a method as simple as dusting the surface of the
asteroid with chalk or charcoal, or perhaps white glass beads.
This would change the
asteroid's reflectivity and allow sunlight to do the work of pushing
the asteroid out of the way.
Nasa is currently
tracking all 1,400 potentially hazardous asteroids so far identified
and predicting their future close approaches and impact
probabilities.
As part of this effort
it is working on the development of an infrared sensor that could
improve its asteroid tracking capabilities, dubbed the Near Earth
Object Camera (NEOCam) sensor.
Once launched, the
space-based telescope would be positioned at a location about four
times the distance between Earth and the moon.
From this lofty perch,
NEOCam could observe the comings and goings of near Earth objects,
including PHAs, without the impediments such as cloud
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