2017 comet's unusual acceleration explained by hydrogen outgassing from ice. In 2017, a mysterious comet dubbed ‘Oumuamua fired the imaginations of scientists and the public alike. It was the first known visitor from outside our solar system, it had no bright coma or dust tail, like most comets, an
astronomer argue that the comet’s mysterious deviations from a hyperbolic path around the sun can be explained by a simple physical mechanism likely common among many icy comets: outgassing of hydrogen as the comet warmed up in the sunlight.
When discovered, ‘Oumuamua had no coma or tail and was too small and too far from the sun to capture enough energy to eject much water, which led astronomers to speculate wildly about its composition and what was pushing it outward.
“For a comet several kilometers across, the outgassing would be from a really thin shell relative to the bulk of the object, so both compositionally and in terms of any acceleration, you wouldn’t necessarily expect that to be a detectable effect,” she said. “But because ‘Oumuamua was so small, we think that it actually produced sufficient force to power this acceleration.”
Jennifer Bergner in her Ph.D. lab at Harvard University. In the background is instrumentation for studying ice chemistry at the frigid temperatures characteristic of interstellar space. Credit: Luke Kelley As more and more telescopes focused on ‘Oumuamua, the astronomers were able to chart its orbit and determine that it had already looped around the sun and was headed out of the solar system.
日本 最新ニュース, 日本 見出し
Similar News:他のニュース ソースから収集した、これに似たニュース記事を読むこともできます。
Scientists explain alien comet 'Oumuamua's strange accelerationThe quirky comet 'Oumuamua, the first interstellar object found visiting our solar system, has been the subject of fascination since being spotted in 2017, including its curious acceleration as it hurtled away from the sun.
続きを読む »
Sorry, E.T. fans: Interstellar visitor 'Oumuamua isn’t an alien spacecraft, it’s just passing gasWe'll probably never know for sure, but this new explanation holds water, scientists say.
続きを読む »
'Oumuamua wasn't an alien spaceship, new study concludesA mysterious interstellar visitor, known as 'Oumuamua, was once believed to be an alien spacecraft, but a new study says that's not true.
続きを読む »
Mystery of our first interstellar visitor may be solvedA team of researchers says ‘Oumuamua was definitely a comet, albeit one with an unusual makeup.
続きを読む »
Scientists think they know why interstellar object 'Oumuamua moved so strangelyA strange comet-like object discovered over 5 years ago was the first known visitor from another solar system. Its movement though space was so odd that scientists struggled to explain it, until now.
続きを読む »