APS April Meeting in Denver, Colorado
I was just in a fascinating session that explored how space and ground-based telescopes are being used to catalogue near Earth objects with a view to spotting asteroids that could be on a collision course with Earth.
One remarkable thing I learned from NASA’s Amy Mainzer is that astronomers predicted an impact in Sudan in 2018 and scientists were able to go to the site and find pieces of the object. Pretty impressive, and good to know that in principle a populated area could be evacuated if a significant impact is expected.
Mainzer said that we have mapped the orbits of about 90% of the “dinosaur killers” near Earth and the effort continues. However, she pointed out that we have only detected about 1% of objects on par with the Chelyabinsk impact of 2013 so there is still much to do.
Planets could be formed by interstellar objects like ’Oumuamua
Also speaking was NASA’s Emily Kramer, who searches for objects using ground-based telescopes. Currently only three instruments are being used (in Arizona, California and Hawaii), which is not ideal. Fortunately, two more telescopes (both in the Southern Hemisphere) will join the hunt next year.
One of the current telescopes (Pan-STARRS) had discovered the interstellar visitor ‘Oumuamua in 2017. Kramer said that the telescope is likely to discover about one such interstellar object every ten years. Indeed the telescope has been running for a decade.
Does she believe the theory that ‘Oumuamua is a light sail of an alien spacecraft? See said that’s “not a popular explanation” in the observing community. And what about the more recent claim that another interstellar object struck Earth in 2014? “Not popular”.
