NASA admits there's 'a chance' that asteroid 2013 TX68 COULD smash into Earth

[lovuian]

http://www.mirror.co.uk/tech/nasa-admits-theres-a-chance-7448889

NASA has dramatically changed its mind about the risks posed by asteroid 2013 TX68 , a 100ft-wide rock which is currently heading towards Earth.

It said there was "a chance" it could plough into our planet next year when it makes another flyby.

However, we are glad to report that NASA thinks the odds of a collision on September 28, 2017, are "no more than 1-in-250-million".

It's like winning the powerball

[SoLeftIAmRight]

1. It's like winning the powerball

Given the choice I would rather win the powerball

[lovuian]

2. me too but it's a

long shot

[ThoughtCriminal]

9. My luck

get both.

[awoke_in_2003]

15. On the same day. nt

[RKP5637]

26. LOL!!!

[underahedgerow]

3. Better call Harry Stamper.

Get those roughnecks ready to blast that thing with a nuclear warhead!

[Brother Buzz]

5. GMTA

[underahedgerow]

10. "Yippee-ki-yay,

motherfucker".

That's my movie sorted for this evening!

[Brother Buzz]

11. You know we're sitting on four million pounds of fuel....

one nuclear weapon and a thing that has 270,000 moving parts built by the lowest bidder. Makes you feel good, doesn't it?



I caught it on Netflix just last week.

[A HERETIC I AM]

16. There was a quote by one of the early Mercury Astronauts....

(At least I think it was Mercury) that was similar.

Something to the effect that he was sitting on top of a several hundred thousand pound bomb built by the lowest bidder on a government contract and the next nearest person was 3 miles away!

[cherokeeprogressive]

22. I think it was Alan Shepard.

Mr. Irreverent. When they asked him to go first he said, "Yeah, I'll give it a shot."

[Brother Buzz]

4. Like winning the powerball, it only takes one to win

Thank Goodness we have studs like Bruce Willis, Ben Affleck, Billy Bob Thornton, and Steve Buscemis to keep us safe.

[dembotoz]

6. trump would build a wall to prevent it

[Blue_In_AK]

7. That's what I heard, as well.

The first pass isn't the dangerous one, it's the second.

[lovuian]

8. I noticed the Russians are working on it

http://www.space.com/7720-russia-attack-asteroid-virtually-threat.html

[Solly Mack]

12. 2013 TX68 should aim for the next GOP debate site.

[randome]

18. It's got Texas' name on it.

[hr][font color="blue"][center]TECT in the name of the Representative approves of this post.[/center][/font][hr]

[NickB79]

13. A 100-ft wide rock would pack quite the punch

Not mass extinction level punch, mind you, but still enough to starve a bunch of us to death through crop failures and weather alternations.

[muriel_volestrangler]

20. About twice the power of the Chelyabinsk meteor, which was 65 ft

It might kill people close to it if it exploded/hit very near a populated area, but not 'crop failures and weather alterations', I think:

During the upcoming March 5 flyby, asteroid 2013 TX68 could fly past Earth as far out as 9 million miles (14 million kilometers) or as close as 11,000 miles (17,000 kilometers). The variation in possible closest approach distances is due to the wide range of possible trajectories for this object, since it was tracked for only a short time after discovery.

Scientists at NASA's Center for NEO Studies (CNEOS) at the Jet Propulsion Laboratory in Pasadena, California, have determined there is no possibility that this object could impact Earth during the flyby next month. But they have identified an extremely remote chance that this small asteroid could impact on Sep. 28, 2017, with odds of no more than 1-in-250-million. Flybys in 2046 and 2097 have an even lower probability of impact.

"The possibilities of collision on any of the three future flyby dates are far too small to be of any real concern," said Paul Chodas, manager of CNEOS. "I fully expect any future observations to reduce the probability even more."

Asteroid 2013 TX68 is estimated to be about 100 feet (30 meters) in diameter. By comparison, the asteroid that broke up in the atmosphere over Chelyabinsk, Russia, three years ago was approximately 65 feet (20 meters) wide. If an asteroid the size of 2013 TX68 were to enter Earth's atmosphere, it would likely produce an air burst with about twice the energy of the Chelyabinsk event.

https://www.nasa.gov/feature/jpl/small-asteroid-to-pass-close-to-earth-march-5

[NickB79]

23. The Chelyabinsk asteroid broke up in mid-air though and only produced an air blast

I was assuming a hard impact and subsequent ejecta pattern. It would depend on the composition of the asteroid.

Given that even a "small" nuclear war between India and Pakistan could result in a global nuclear winter and crop failures, and a 100-ft wide asteroid would be hitting with the force of many nukes at once, I feel my hypothesis is still plausible: http://www.livescience.com/44380-small-nuclear-war-could-trigger-catastrophic-cooling.html

[muriel_volestrangler]

25. But it's not many nukes at once

Asteroids with a diameter of 7 meters enter Earth's atmosphere with as much kinetic energy as the atomic bomb dropped on Hiroshima (approximately 16 kilotons of TNT) about every 5 years, but the air burst is reduced to just a third, or about 5 kilotons of TNT.[7] These ordinarily explode in the upper atmosphere, and most or all of the solids are vaporized.[9] Objects with a diameter of roughly 50 m (164 ft) strike Earth approximately once every thousand years,[10] producing explosions comparable to the one known to have detonated roughly 8.5 kilometers (28,000 ft) above Tunguska in 1908.[11]

https://en.wikipedia.org/wiki/Impact_event

In the Wikipedia table, a 98ft diameter asteroid has kinetic energy at atmospheric entry of 1.3MT. They don't calculate the impact energy for one that small (because it would still probably explode in the air, like Tunguska), but extrapolating from the larger ones they do do the calculation for, it would lose well over half its energy - in fact, the airburst would be more damaging (the calculations come from Imperial College, London - a sample one).

It's equivalent to one modest thermonuclear bomb - the kind of thing they tested many times without affecting weather, and that do hit Earth every few hundred years.

[Ghost Dog]

29. Given the quoted variation in possible trajectaries

on the first pass, I suggest the probability that the quoted probability of a hit on the second pass is accurate is not very high.

[muriel_volestrangler]

30. The probability of a hit on the 2nd is based on the probabilities of where it could go on the 1st

The probability of a hit is correct. It is the probability of the asteroid hitting the Earth, in their models, given the fuzziness of the information they currently have. It's not that there will be a series of random events that could produce a hit.

[Ghost Dog]

32. I'd call it a fuzzy probability.

Not a big one, anyway. I'd like to see a Richter-like scale for these events, rather than the megaton analogy.

[muriel_volestrangler]

33. See #31 - NASA is saying there is zero probability of a hit in the next century

The British tabloids got it wrong. On Feb 25th, NASA revised its calculation (because it got new observations) and changed their estimate of a hit in 2017 from 1 in 250 million (what they said on Feb 2nd) to zero (what they said Feb 25th). They also say that this March, it won't pass closer than 15,000 miles, when they had said 11,000 earlier.

See, for instance, a site that reports on space, and so reports things like this better than British tabloids (a Google news search shows that it's only the British tabloids, and a few web-only sites, that are still quoting the 1 in 250 million chance):

Additional observations of asteroid 2013 TX68 have been obtained, refining its orbital path and moving the date of the asteroid's Earth flyby from March 5 to March 8.

The observations, from archived images provided by the NASA-funded Pan-STARRS asteroid survey, enabled scientists at NASA's Center for Near-Earth Object Studies (CNEOS) at the Jet Propulsion Laboratory in Pasadena, California, to refine their earlier flyby and distance predictions, reconfirming that the asteroid poses no threat to Earth.
...
CNEOS's new prediction for 2013 TX68 is that it will fly by roughly 3 million miles (5 million kilometers) from our planet. There is still a chance that it could pass closer, but certainly no closer than 15,000 miles (24,000 kilometers) above Earth's surface.

The new observations also better constrain the path of 2013 TX68 in future years; CNEOS has determined that 2013 TX68 cannot impact Earth over the next century.

http://www.spacedaily.com/reports/Small_Asteroid_to_Pass_Close_to_Earth_March_8_999.html

But the thing about a probability is that you don't quote it with an uncertainty; any uncertainty just raises the improbability. Rather than saying "it's a 1 in a 1000 probability, plus or minus something", you say "it's a 1 in a 1,500 probability".

[Nitram]

14. Like winning the Powerball, except that in this case...

...the odds are in our favor.

[A HERETIC I AM]

17. 70% chance it lands in water. n/t

[Shandris]

19. That's funny, that lines up (nearly) with another forecast apocalypse date.

The 23rd. Seems some kind of Revelations linky thing about constellations, verses, and the placement of the stars.

That'll be more than enough to get the End Timers fired up.

[Warren DeMontague]

21. Good thing ive been practicing on how to deal with exactly this scenario

In Kerbal Space Program.

[Tommy_Carcetti]

24. ............

Although, if we were nine months into a President Trump administration, I'd gladly welcome the prospect of worldwide species annihilation.

[lunatica]

27. 100 foot wide asteroid isn't big enough to destroy most life on the planet

And it would probably break up upon entry into our atmosphere so it would create damage, but nothing like the 10 kilometer wide one that killed off the dinosaurs.

[Reter]

28. Only 100 foot

Not a world changer anyway (but it can still do a lot of damage).

[muriel_volestrangler]

31. I've just realised, the Mirror has got this wrong - NASA is now saying *no* chance of a hit

Here's the NASA page: https://www.nasa.gov/feature/jpl/small-asteroid-to-pass-close-to-earth-march-5

It's dated, at the top, Feb. 2, 2016. And it has, in normal font, this paragraph:

"During the upcoming March 5 flyby, asteroid 2013 TX68 could fly past Earth as far out as 9 million miles (14 million kilometers) or as close as 11,000 miles (17,000 kilometers). The variation in possible closest approach distances is due to the wide range of possible trajectories for this object, since it was tracked for only a short time after discovery.

Scientists at NASA's Center for NEO Studies (CNEOS) at the Jet Propulsion Laboratory in Pasadena, California, have determined there is no possibility that this object could impact Earth during the flyby next month. But they have identified an extremely remote chance that this small asteroid could impact on Sep. 28, 2017, with odds of no more than 1-in-250-million. Flybys in 2046 and 2097 have an even lower probability of impact."

But, above that, in bold type, it has:

UPDATED ON FEB. 25 AT 2:40 P.M. PT:

Additional observations of asteroid 2013 TX68 have been obtained, refining its orbital path and moving the date of the asteroid’s Earth flyby from March 5 to March 8.

The observations, from archived images provided by the NASA-funded Pan-STARRS asteroid survey, enabled scientists at NASA's Center for Near-Earth Object Studies (CNEOS) at the Jet Propulsion Laboratory in Pasadena, California, to refine their earlier flyby and distance predictions, reconfirming that the asteroid poses no threat to Earth.

"We already knew this asteroid, 2013 TX68, would safely fly past Earth in early March, but this additional data allow us to get a better handle on its orbital path," said Paul Chodas, manager of CNEOS. "The data indicate that this small asteroid will probably pass much farther away from Earth than previously thought."

Marco Micheli of the European Space Agency's NEO Coordination Centre (NEOCC/SpaceDys) in Frascati, Italy, is the astronomer who identified the object in the archived images, measured its position, and provided these observations to the Minor Planet Center in Cambridge, Massachusetts.

CNEOS's new prediction for 2013 TX68 is that it will fly by roughly 3 million miles (5 million kilometers) from our planet. There is still a chance that it could pass closer, but certainly no closer than 15,000 miles (24,000 kilometers) above Earth's surface. The new observations also better constrain the path of 2013 TX68 in future years; CNEOS has determined that 2013 TX68 cannot impact Earth over the next century.

"There is no concern whatsoever regarding this asteroid – unless you were interested in seeing it with a telescope," said Chodas. "Prospects for observing this asteroid, which were not very good to begin with, are now even worse because the asteroid is likely to be farther away, and therefore dimmer than previously believed."

So the change of mind that NASA had was to go from a 1 in 250-million chance to no chance.