A comet strike may have triggered the Paleocene-Eocene Thermal Maximum (PETM), a rapid warming of the Earth caused by an accumulation of atmospheric carbon dioxide 56 million years ago. Atmospheric carbon dioxide increased rapidly during the PETM, and an accompanying spike in global temperatures of about 5 to 8 °C lasted for about 150,000 years.
As it orbits Jupiter, the icy surface of Europa heaves and falls with the changing pull of its parent planet’s gravity, creating enough heat to likely support a global ocean beneath the Jovian moon’s solid shell. Experiments by geoscientists suggest that this process, called tidal dissipation, could create far more heat in Europa’s ice than scientists had previously assumed.
Columbia University astronomers provide additional evidence that a pair of closely orbiting black holes deep in the Virgo constellation is causing the rhythmic flashes of light coming from quasar PG 1302-102. Separated by a mere light-week, the black holes are spiralling toward a collision so powerful it will send a burst of gravitational waves surging through the fabric of space-time.