On February 15, 2013, a 17 meter-long meteor exploded in the air above Chelyabinsk, Russia, releasing energy equivalent to the detonation of approximately 30 Hiroshima bombs, and injured over a thousand people. According to NASA, it was the largest meteor impact in about 100 years. The following day, the asteroid DA14, measuring three times as large, zipped past the earth at a hair’s breadth of 17,100 miles. Had it collided with the Earth, it would have no doubt triggered an even more cataclysmic aftermath. The unexpectedness of the Russian meteor and the temporal proximity of both events have captured the imagination of the public regarding apocalyptic large impacts. But just how often do large impacts occur and how greatly do they pose as existential threats to life on earth?
Could we someday be able to regenerate organs or tissues like house lizards?
Are we alone in this world? If we are not, why haven’t we found any extraterrestrial intelligence yet? Gabrielle Chong, a student at Wellesley College, US, explains possible philosophical answers to this paradox also known as the Fermi’s Paradox.