Shulou(Shulou.com)11/24 Report--

CTOnews.com May 16-The James Webb Space Telescope has spotted a rare comet, 238P / Read, in the asteroid belt between Jupiter and Mars, surrounded by water vapor.

The observation represents another scientific breakthrough for the James Webb Space Telescope (JWST) and represents the first detection of water vapor in the main asteroid belt, suggesting that water from the early solar system may have been preserved in the main asteroid belt as ice. The findings were published in Nature (CTOnews.com DOI:10.1038 / s41586-023-06152-y).

Source: NASA, ESA

"We have seen objects in the main belt with all the characteristics of comets in the past, but only with these precise spectral data from the James Webb Space Telescope can we say 'yes' and this is definitely an effect due to ice," said Michael Kelly, a University of Maryland astronomer and lead investigator on the study, in a statement. "With observations of Comet Read with the James Webb Space Telescope, we can now prove that water ice from the early solar system can be preserved in the asteroid belt. "

The discovery of water vapor around Comet 238P / Read may greatly advance the theory that water is an important component of life and was delivered to Earth from space by comets, but there is also a mystery to studying the comet: carbon dioxide, which astronomers thought could be found, has not been found on the comet at all.

The team was even more surprised by the lack of carbon dioxide around comet 238P/ Read than water vapor, because this compound, which previously accounted for 10 percent of the comet's volatile matter, is easily vaporized by the sun.

The team says there are two possible reasons for comet 238P / Read's lack of carbon dioxide. For one thing, the comet may have contained carbon dioxide during its formation, but since the sun eventually lost carbon dioxide.

"Long-term exposure to the asteroid belt can do that-carbon dioxide evaporates more easily than water ice and can seep out over billions of years," Kelly said. "

Another theory about the lack of carbon dioxide is that the main-belt comet may have formed in a region of the solar system that lacks this compound.

It is well known that comets 'coma and tail are composed of solid ice, which is converted directly into gas during sublimation as the comet approaches the sun. This sublimation is why astronomers infer that all comets come from the Kuiper Belt or the Oort Cloud beyond Neptune (the Oort Cloud is thought to exist in the outermost regions of the solar system, both of which protect ice in these objects from solar radiation and thus preserve it, while sites near Mars near the Sun may not).

Of course,"main-belt comets" are a fairly new classification, and comet 238P / Read is one of three objects that helped establish this family of comets closer to Earth. Astronomers had not been sure whether these ice bodies could also preserve frozen water, but this is the first conclusive evidence that they could.

"As far as we know, our water-filled world is unique in the universe and full of life, which is a mystery-we are not sure how all this water got here," study co-author Stefanie Milam, a Webb planetary science associate project scientist, said in a statement. "

The team's goal now is to find out if their compositions are similar by looking at other similar rare comets other than comet 238P / Read. This may require further observations using the James Webb Space Telescope and other telescopes, as well as in situ missions that may collect samples from main-belt comets.

"These objects in the asteroid belt are small and faint, and with the James Webb Space Telescope, we can finally understand them and draw some conclusions," said co-author Heidi Hammel, an astronomer at the Alliance of Research Universities. In any case, the thought of finding that answer is exciting enough. "

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.