Jupiter’s moon spews lava for two weeks
Imagine looking up at the moon and seeing super-volcanos erupt for two weeks straight. That was the scene last year for Jupiter’s moon Io, a celestial body roughly the same size as our lunar companion.
However, unlike our moon, Io is highly volcanic and due to it’s low gravity the eruptions can shoot debris high into space. Scientists at JPL and UC Berkeley have been monitoring the events as a way to understand what early Earth was like.
There are five special points where a small mass can orbit in a constant pattern with two larger masses (such as a satellite with respect to the Earth and Moon). The Lagrange Points, named in honor of Italian-French mathematician Joseph-Louis Lagrange, are positions where the gravitational pull of two large masses precisely equals the centripetal force required for a small object to move with them. This mathematical problem, known as the “General Three-Body Problem” was considered by Lagrange in his prize winning paper (Essai sur le Problème des Trois Corps, 1772).
The five Sun–Earth Lagrangian points are called SEL1–SEL5, and similarly those of the Earth–Moon system EML1–EML5, etc. Orbits around Lagrangian points offer unique advantages that have made them a good choice for performing certain spacecraft missions.
For example the Sun–Earth L1 point is useful for observations of the Sun, as the Sun is always visible without obstructions by the Earth or the Moon. SOHO, the ESA/NASA solar spacecraft is positioned there.
read descriptions about invidual L-points here
As hemp makes a comeback in the U.S. after a decades-long ban on its cultivation, scientists are reporting that fibers from the plant can pack as much energy and power as graphene, long-touted as the model material for supercapacitors. They’re presenting their research, which a Canadian start-up company is working on scaling up, at the 248th National Meeting & Exposition of the American Chemical Society (ACS), the world’s largest scientific society.
David Mitlin, Ph.D., explains that supercapacitors are energy storage devices that have huge potential to transform the way future electronics are powered. Unlike today’s rechargeable batteries, which sip up energy over several hours, supercapacitors can charge and discharge within seconds. But they normally can’t store nearly as much energy as batteries, an important property known as energy density. One approach researchers are taking to boost supercapacitors’ energy density is to design better electrodes. Mitlin’s team has figured out how to make them from certain hemp fibers — and they can hold as much energy as the current top contender: graphene.
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