The accumulated evidence from the Chelyabinsk meteorite now suggests the risk of large asteroid impacts might be ten times greater than previously estimated.
The accumulated evidence from the Chelyabinsk meteorite now suggests the risk of large asteroid impacts might be ten times greater than previously estimated.
The Chelyabinsk asteroid had approached Earth from a region of the sky that is inaccessible to ground-based telescopes. In the 6 weeks before the impact, it would have been visible above the horizon only during the daytime, when the sky is too bright to see objects of its size, says Borovička.
“The residual impact risk — from asteroids with yet-unknown orbits — is shifting to small-sized objects,” says Peter Brown, a planetary scientist at the University of Western Ontario in London, Canada, and an author on the Nature papers.
Of the millions of estimated near-Earth asteroids 10–20 metres in diameter, only about 500 have been catalogued. Models suggest that an object the size of the Chelyabinsk asteroid hits Earth once every 150 years on average, Brown says. But the number of observed impacts exceeding 1 kiloton of TNT over the past 20 years alone hints at an actual impact risk that may be an order of magnitude larger than previously assumed,
The data also now suggests that the Chelyabinsk asteroid was twice as big as previously thought, and that it had an almost identical orbit to a much larger already known asteroid.
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The accumulated evidence from the Chelyabinsk meteorite now suggests the risk of large asteroid impacts might be ten times greater than previously estimated.
The Chelyabinsk asteroid had approached Earth from a region of the sky that is inaccessible to ground-based telescopes. In the 6 weeks before the impact, it would have been visible above the horizon only during the daytime, when the sky is too bright to see objects of its size, says Borovička.
“The residual impact risk — from asteroids with yet-unknown orbits — is shifting to small-sized objects,” says Peter Brown, a planetary scientist at the University of Western Ontario in London, Canada, and an author on the Nature papers.
Of the millions of estimated near-Earth asteroids 10–20 metres in diameter, only about 500 have been catalogued. Models suggest that an object the size of the Chelyabinsk asteroid hits Earth once every 150 years on average, Brown says. But the number of observed impacts exceeding 1 kiloton of TNT over the past 20 years alone hints at an actual impact risk that may be an order of magnitude larger than previously assumed,
The data also now suggests that the Chelyabinsk asteroid was twice as big as previously thought, and that it had an almost identical orbit to a much larger already known asteroid.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
Nature is pretty wild, in addition to affecting tidal forces on the earth, it seems as if the moon also has been in the way of many asteroids, sparing the earth of a lot more impacts than it otherwise might have had.