Guest post by Thomas Sumner
Methane, not an alien spacecraft crash, is probably responsible for the 30-meter-wide crater that suddenly appeared in Siberia in mid-July.
While air normally contains just 0.000179 percent methane, air near the bottom of the crater was composed of 9.6 percent methane, Nature reports. Researchers suspect that rising summer temperatures in the region thawed permafrost in the ground. As the soil defrosted, methane gas trapped in the permafrost pooled underground before bursting to the surface and ripping a hole in the ground.
Scientists believe that as regional temperatures rise, these kinds of craters could become more common.