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This 2016 answer to Does Bennu pose a risk to Earth? And how can OSIRIS-REx's mission save us? says:

Does Bennu pose a risk to Earth?: recent calculations produced a cumulative probability of 1 in 1410 (or 0.071%) of impact with Earth in the period 2169 to 2199.

and the first comment below it says:

Those sound like terrible odds.

to which I agree.

Precision tracking of OSIRIS REx itself (in orbit around Bennu) along with all the data collected so far by its scanning of the surface would have already improved understanding of the evolution of its trajectory over the next 200 years. Have new or updated estimates of the likelihood of collision with Earth been made?

enter image description here

borrowed from How will OSIRIS-REx scan and characterise the near-earth asteroid Bennu?

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Wikipedia covers this.

The 1 in 1410 probability comes from Long-term impact risk for (101955) 1999 RQ36 in 2009 which notes...

The analysis of impact possibilities so far in the future is strongly dependent on the action of the Yarkovsky effect, which raises new challenges in the careful assessment of longer term impact hazards.

With better observations the prediction has been refined. According to CNEOS the cumulative probability is now 1 in 2700 between 2175 and 2199.

Analysis based on 478 observations spanning 4879.7 days (1999-Sep-11.4 to 2013-Jan-20.1)

That would not include any data from OSIRIS-REX which launched in 2016.


Note that Bennu's cumulative Palermo Scale is -1.71. While it is one of the highest we're currently tracking, -1.71 means its a below average risk but merits close monitoring. 0 is average. Which is to say, something else that size is more likely to hit us before then.

It's not predicted to be a threat for 160 years by which time we should have the means to adjust its orbit, assuming something else hasn't wiped out civilization by then.

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    $\begingroup$ Those still sound like terrible odds. $\endgroup$ – Richard Dec 7 '19 at 7:40
  • $\begingroup$ @Richard Obviously one wants the odds to be as low as possible. Its cumulative Palermo Scale of -1.71 is one of the highest we're currently tracking, -1.71 means its a below average risk but merits close monitoring. 0 is average. Which is to say, something else that size is more likely to hit us before then. And it's not predicted to be a threat for 160 years by which time we should be able to adjust its orbit. $\endgroup$ – Schwern Dec 7 '19 at 19:54
  • $\begingroup$ I plan to live long enough to care personally. $\endgroup$ – Richard Dec 7 '19 at 20:02

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