Free Astronomy Magazine January-February 2018

29 JANUARY-FEBRUARY 2018 EARTH S everal samples of material taken from the Chicxulub crater using the Liftboat Myrtle platform's auger. They are essentially a mix- ture of terrestrial rock and residual material from the asteroid. very probably have taken a deeply different path from the one that led to the appearance of the human being. Kaiho and Oshima com- ment in more detail be- low on the results of their simulations in Scientific Reports . Please note that the two researchers indi- cate soot with the abbreviation BC, from black carbon, and indicate the quantities in teragrams, Tg (1 Tg = 1 million tons). “We estimated climate changes caused by BC injection due to the Chicxulub asteroid impact for five quantities of BC (20, 200, 500, 1500, and 2600-Tg BC ejection cases) using global climate model calculations. Although BC in the troposphere was effi- ciently removed from the atmosphere by precipitation (within approximately 1 week), BC in the stratosphere had a longer lifetime and was gradually deposited on the surface, on a scale of several years. The stratospheric BC rapidly reduced the sun- light reaching the Earth’s surface, which led to a cooling of the tropospheric atmo- sphere and ocean, and a decrease in pre- cipitation on a global scale. These climate