Researchers are proposing the idea of using our planet itself as a “paleo-detector” to solve the enduring mystery of dark matter–Earth has been orbiting through interplanetary space for some 4.5 billion years, during which time it must have been penetrated by a new form of dark matter known as massive, super-heavy gravitinos. Strong and electromagnetic interactions with known matter may make this new form of dark matter particles with large mass, easier to track down despite their extreme rarity.
“It must have been a supernova, not so near as to kill us but not too far to be diluted in space,” said physicist Dominik Koll, at Australian National University, about the new discovery that our planet probably picked up stray particles not naturally produced on Earth while traveling through the Local Interstellar Cloud (image above), also known as the Local Fluff, for somewhere between 40,000 and 150,000 years and will probably not emerge for another 20,000 years.
“It may be that our role on this planet is not to worship God – but to create him, wrote Arthur C Clarke, author of 2001 A Space Odyssey. Clarke also famously warned against a mission to explore the most intriguing of Jupiter’s 79 moons, which has now been given the green light to proceed to the final stages of development of NASA’s Europa Clipper Mission.
“We know there were periods when the surface of Mars was frozen; we know there were periods when water flowed freely,” said Briony Horgan with Purdue University at the at the Goldschmidt Geochemistry Conference in Barcelona. “But we don’t know exactly when these periods were, and how long they lasted. We have never sent unmanned missions to areas of Mars which can show us these earliest rocks, so we need to use Earth-bound science to understand the geochemistry of what may have happened there.
An experiment to test a popular theory that dark energy –the unknown force that is causing the universe to expand at an accelerating rate– is a ‘fifth’ force that acts on matter has found no evidence of its existence. “The discovery of dark energy has greatly changed how we think about the laws of nature,” said Edward Witten, one of the world’s leading theoretical physicist at the Institute for Advanced Study in Princeton, N.J. who has been compared to Newton and Einstein.
