Rumors on the Internet: How to Separate Facts from Nonsense about Asteroid Impacts

asteroid itokawa
Itokawa is representative of Near-Earth Asteroids, and was previously given the provisional designation 1998 SF36. Itokawa was discovered by the LINEAR survey in 1998 and visited by the Hayabusa spacecraft in 2005. The asteroid is 535m long and 294m wide. Like all other known potentially-hazardous asteroids, Itokawa’s orbit does not present any danger to Earth for centuries to come. Image Credit: JAXA/ISAS

By Michael Busch, Planetary Scientist – SETI Institute 

Since earlier this year, a rumor has been floating around the Internet that a large asteroid will impact in the Caribbean in September 2015, causing global destruction. This rumor is completely false.

As stated by NASA’s Near-Earth Object office, there are zero known asteroids or comets that can impact Earth in the foreseeable future.  All known potentially hazardous asteroids have less than a 0.01% chance of impacting Earth any time in the next 100 years. Thanks to work by astronomers and engineers in many countries over the past 20 years, we have discovered all potentially hazardous asteroids larger than 1 km in diameter, and we track their orbits. Many thousands of Near-Earth Objects (NEO) have been identified, cataloged and tracked, in sizes down to under 30 meters in diameter. These efforts have ruled out an impact by any asteroid large enough to cause global problems for the next century. 

That doesn’t stop the circulation of false claims of pending asteroid doomsday nearly every year. For example, in September 2014, an asteroid called 2014 RC passed within 40,000 km of Earth. This was its closest approach to us until at least the year 2200, and it is a very small asteroid – 12 by 22 meters. 2014 RC posed no danger to anyone. And yet, there was a flurry of claims that it would kill us all, requiring scientists to carefully explain the real situation. Doing this every year is frankly rather tiresome.

To prevent unnecessary panic, here are a few ways to separate fact from fiction, if you hear or see a story about a future asteroid impact:

The first thing to check is where the story comes from.  A pseudonymous blogger or a many-times-forwarded email referring to unnamed sources is not how we get reliable information about astronomy. Here is how asteroid discovery really happens: There are several astronomical survey programs based in different places (especially in Hawaii, Arizona, and in low-Earth orbit satellites). These cover large areas of the sky every night, looking for asteroids.  Their observations are reported to the International Astronomical Union and cross-checked against a database of known objects. New discoveries are publicly announced within at most one day!

Any story about a potentially hazardous asteroid should say who discovered the asteroid, when it was discovered, and give a provisional designation – the unique name given to each asteroid in order of discovery.  For example, 2014 RC was discovered on August 31, 2014 by the Catalina Sky Survey near Tucson, Arizona, and then observed again on September 1 by the Pan-STARRS 1 telescope on Haleakala (on the island of Maui).

Also, is the story original?  Rumors have a tendency to be recycled. The current rumor is a recycling of a previous rumor from the middle of 2013. Interest in that story dropped to zero rapidly after September of that year, but it was rebranded and resurfaced early this year and the Internet picked it up again.

Finally, if a story alleges a conspiracy between scientists or governments to conceal evidence of a hazardous asteroid you can reject it immediately – that’s not how astronomy works.  Asteroid discoveries are made public within 24 hours or less because it’s important to have anyone with a telescope who can observe the asteroid do so – to prevent the asteroid from being lost.  

And concealing an asteroid discovery would be pretty much impossible even if you wanted to: anyone with a good enough telescope can find it for themself. An actual announcement of a potentially hazardous asteroid discovery would also include information about how to observe it, to improve knowledge of its trajectory. 

It would be nice to see the end of asteroids-as-doomsday rumors, but given how often they’ve shown up in the past there will no doubt be more fear-mongering in the future. I hope this piece will reassure you about the fate of our planet, and help you recognize these doomsday stories as false when you encounter them.