Marsquake!

The InSight Lander Seismometer Detects a likely Mars Quake – recorded early last month a 40-second long low rumble was detected by seismic sensors placed on the surface to determine if and to what degree Mars is seismically active. The duration wasn’t long enough to determine much about Martian tectonic activity, but still offered evidence that the interior of the red planet contimues to cool.

A giant asteroid smashed into Earth 66 million years ago off the coast of what’s now Mexico. Set off by the impact, an immense earthquake equivalent to a magnitude 10 or even 11.5 sent seismic waves pulsing through Earth’s crust, according to researchers reporting online in the Proceedings of the National Academy of Sciences.At least 75 percent of species, including all nonbird dinosaurs, died out. Tiny traces of the Chixulub Meteor Impact Event appear to be preserved in a meter-thick layer of rock in southwestern North Dakota.

The site, found in the Hell Creek Formation and dubbed Tanis, represents a unique snapshot of what happened on land in the immediate aftermath of the impact, says paleontologist Robert DePalma of the University of Kansas in Lawrence. But it’s not the only plausible sequence of events that could have happened,” Whiteside says. And there may be no way to know for sure if the scenario is the right one, or exact timing of the seismic waves’ arrival, because there are so many unknowns about the lay of the land 66 million years ago.

The 2019 Philadelphia Science Festival comes to a conclusion today with a celebration along the Benjamin Franklin Parkway featuring more than 100 hands-on activities and demonstrations.

Turning to dark sky highlights: Mars is still visible in the west after sunset, Jupiter well up in the east by midnight; Venus, Saturn AND Jupiter can be seen in the pre-dawn sky between 5:00am and 5:45am.