Thomas Neville Earth Science IIH

Current Event #2

Citation: Morelle, Rebecca. "Asteroid Hit Rate 'underestimated'" BBC News. N.p., 6 Nov. 2013. Web. 23 May 2014

URL: http://www.bbc.com/news/science-environment-24839601

     In light of the 19-meter wide meteorite that landed in Russia last year researchers have been combing over sensor data and infrasound sensors used by the U.S. government. These sensors are in place to detect nuclear weapons but can also be used to capture blasts caused by asteroid impacts. A study conducted by the researchers found that the sensors had detected up to 60 asteroids as long as 20 meters had smashed into Earths atmosphere, a number far higher than any previous study had shown. These asteroids were previously unreported because they exploded either over the ocean or in highly remote areas. The numbers extrapolated from the sensors show that asteroids hit the Earth at a much higher frequency than previously thought. For example: from telescopic information alone an astronomer would estimate that an event like the meteorite that landed in Russia last year would happened every 150 years or so. However, sensor data suggests that events like the Russian meteorite occur roughly every 30 years. This in turn suggests that events like the Tunguska impact of 1908 that flattened thousands of square miles of Siberian forest most likely happen every few hundred years rather than every few thousand.

     The study makes it clear that asteroids and more importantly large asteroids hit Earth much more often than previously thought, and that our current detection methods are not good enough to detect the asteroids before they hit. Astronomers can use the data obtained through the sensors to improve their own detection methods, hopefully closing the gap between what the sensors detected and what astronomers can detect before an asteroid makes impact. Peter Brown, a lead researcher on the study, suggests that even a few days to a weeks notice before an asteroid hits Earth would be invaluable both for researchers who want to study the meteorite on impact and so local governments could have time to prepare clean up crews and possibly even evacuate citizens close to the impact site. However, The most important effect this study should have on society is on how the public views the chances of an asteroid hitting Earth. Public support and funding is needed for astronomers to continue their research with the most cutting edge technology available. If asteroid strikes aren’t considered a threat to the public then governments won’t have as much of an incentive to fund astronomy research, research that is necessary to detect “Earth-killer” asteroids that could wipe out the human race before they could be diverted out of Earth’s way.

    

      I find that the article lacks specific information on how the sensor data detected the asteroid impacts, instead simply focusing on the fact that they did. Also the author did not explain exactly how these “sensors” worked or what “infrasound” is. These details should not be missing especially since the sensors the author is describing make up the main body of evidence for the study. Other than that I find that the details and statistics provided in the article are more than sufficient and I like that the author went straight to the source and talked to the lead professor on the study, Peter Brown. I think that the article would improve greatly if it described in greater detail how the sensors used in the study worked, but for the most part I think that the author put in enough data to properly inform the reader on what the study means for humanity.