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New Satellite Experiment Helps Confirm Einstein's Equivalence Principle (presse.cnes.fr)
Part of Einstein's theory of general relativity posits that gravity equals inertial mass -- and for the first time in 10 years, there's new evidence that he's right. Slashdot reader orsayman reports:
Most stories around space today seem to revolve around SpaceX, but let's not forget that space is also a place for cool physics experiments. One such experiment currently running into low orbit is the MICROSCOPE satellite launched in 2016 to test the (weak) Equivalence Principle (also knows as the universality of free fall) a central hypothesis in General Relativity.
The first results confirm the principle with a precision ten times better than previous experiments. And it's just the beginning since they hope to increase the precision by another factor of 10. If the Equivalence Principle is still verified at this precision, this could constrain or invalidate some quantum gravity theories. For those of you who are more satellite-science oriented, the satellite also features an innovative "self destruct" mechanism (meant to limit orbit pollution) based on inflatable structures described in this paper.
"The science phase of the mission began in December 2016," reports France's space agency, "and has already collected data from 1,900 orbits, the equivalent of a free fall of 85 million kilometres or half the Earth-Sun distance."
The first results confirm the principle with a precision ten times better than previous experiments. And it's just the beginning since they hope to increase the precision by another factor of 10. If the Equivalence Principle is still verified at this precision, this could constrain or invalidate some quantum gravity theories. For those of you who are more satellite-science oriented, the satellite also features an innovative "self destruct" mechanism (meant to limit orbit pollution) based on inflatable structures described in this paper.
"The science phase of the mission began in December 2016," reports France's space agency, "and has already collected data from 1,900 orbits, the equivalent of a free fall of 85 million kilometres or half the Earth-Sun distance."
Said it before and I say it again. North Korea didn't need to go to the expense of building nukes. They just need to pack a few tonnes of sand around some high explosives, launch it on a rocket into retrograde orbit, and blow it up a few hundred miles high if threatened. Ain't asymmetric escalation a bitch when you're fighting the little guy with a big sting!