"/>

      <label id="xi47v"><meter id="xi47v"></meter></label>

      Second nearest star system may be "habitable" in terms of X-ray radiation: study

      Source: Xinhua    2018-06-07 04:01:38

      WASHINGTON, June 6 (Xinhua) -- A new study involving monitoring of nearest stars beyond our Sun revealed that one of them might be friendlier to life than the Sun in terms of X-ray radiation.

      The United States space agency NASA said on Wednesday in a news release that any planets orbiting the two brightest stars in the Alpha Centaur system were likely not being pummeled by large amounts of X-ray radiation from their host stars.

      Alpha Centauri is a triple star system located just over four light years, or about 40 trillion kilometers, from the Earth.

      "Because it is relatively close, the Alpha Centauri system is seen by many as the best candidate to explore for signs of life," said Tom Ayres with the University of Colorado Boulder.

      "The question is, will we find planets in an environment conducive to life as we know it?" said Ayres.

      X-rays and related space weather effects are bad for unprotected life, directly through high radiation doses and indirectly through stripping away planetary atmospheres.

      The stars in the Alpha Centauri system include a pair called "A" and "B," which orbit relatively close to each other.

      Alpha Cen A is a near twin of our Sun in almost every way, including age, while Alpha Cen B is somewhat smaller and dimmer but still quite similar to the Sun.

      The third member, Alpha Cen C, also known as Proxima, is a much smaller red dwarf star that travels around the AB pair in a much larger orbit that takes it more than 10,000 times farther from the AB pair than the Earth-Sun distance.

      Proxima currently holds the title of the nearest star to Earth, and AB is a very close second, according to NASA.

      The Chandra data revealed that the prospects for life in terms of current X-ray bombardment were actually better around Alpha Cen A than for the Sun, and Alpha Cen B fares only slightly worse.

      Proxima, on the other hand, is a type of active red dwarf star known to frequently send out dangerous flares of X-ray radiation, and is likely hostile to life, according to NASA.

      The findings came after more than a decade observation by NASA's Chandra X-ray Observatory.

      "This is very good news for Alpha Cen AB in terms of the ability of possible life on any of their planets to survive radiation bouts from the stars," said Ayres. "Chandra shows us that life should have a fighting chance on planets around either of these stars."

      However, the bad news is that, although there is one remarkable Earth-size planet around Proxima, astronomers have till now failed to find exoplanets around Alpha Cen A and B.

      Planet-hunting around these stars has proved more difficult recently due to the orbit of the pair, which has drawn the two bright stars close together on the sky over the past decade.

      Planets in the habitable zone around Proxima receive an average dose of X-rays about 500 times larger than the Earth, and 50,000 times larger during a big flare, according to NASA.

      Editor: yan
      Related News
      Xinhuanet

      Second nearest star system may be "habitable" in terms of X-ray radiation: study

      Source: Xinhua 2018-06-07 04:01:38

      WASHINGTON, June 6 (Xinhua) -- A new study involving monitoring of nearest stars beyond our Sun revealed that one of them might be friendlier to life than the Sun in terms of X-ray radiation.

      The United States space agency NASA said on Wednesday in a news release that any planets orbiting the two brightest stars in the Alpha Centaur system were likely not being pummeled by large amounts of X-ray radiation from their host stars.

      Alpha Centauri is a triple star system located just over four light years, or about 40 trillion kilometers, from the Earth.

      "Because it is relatively close, the Alpha Centauri system is seen by many as the best candidate to explore for signs of life," said Tom Ayres with the University of Colorado Boulder.

      "The question is, will we find planets in an environment conducive to life as we know it?" said Ayres.

      X-rays and related space weather effects are bad for unprotected life, directly through high radiation doses and indirectly through stripping away planetary atmospheres.

      The stars in the Alpha Centauri system include a pair called "A" and "B," which orbit relatively close to each other.

      Alpha Cen A is a near twin of our Sun in almost every way, including age, while Alpha Cen B is somewhat smaller and dimmer but still quite similar to the Sun.

      The third member, Alpha Cen C, also known as Proxima, is a much smaller red dwarf star that travels around the AB pair in a much larger orbit that takes it more than 10,000 times farther from the AB pair than the Earth-Sun distance.

      Proxima currently holds the title of the nearest star to Earth, and AB is a very close second, according to NASA.

      The Chandra data revealed that the prospects for life in terms of current X-ray bombardment were actually better around Alpha Cen A than for the Sun, and Alpha Cen B fares only slightly worse.

      Proxima, on the other hand, is a type of active red dwarf star known to frequently send out dangerous flares of X-ray radiation, and is likely hostile to life, according to NASA.

      The findings came after more than a decade observation by NASA's Chandra X-ray Observatory.

      "This is very good news for Alpha Cen AB in terms of the ability of possible life on any of their planets to survive radiation bouts from the stars," said Ayres. "Chandra shows us that life should have a fighting chance on planets around either of these stars."

      However, the bad news is that, although there is one remarkable Earth-size planet around Proxima, astronomers have till now failed to find exoplanets around Alpha Cen A and B.

      Planet-hunting around these stars has proved more difficult recently due to the orbit of the pair, which has drawn the two bright stars close together on the sky over the past decade.

      Planets in the habitable zone around Proxima receive an average dose of X-rays about 500 times larger than the Earth, and 50,000 times larger during a big flare, according to NASA.

      [Editor: huaxia]
      010020070750000000000000011105521372356741
      主站蜘蛛池模板: 国产真人无码作爱免费视频| 欧洲乱码伦视频免费国产| 可以免费观看的毛片| 亚洲欧洲美洲无码精品VA| 久久久WWW成人免费精品| 亚洲AV无码码潮喷在线观看 | 日韩在线看片免费人成视频播放| 亚洲精品国产情侣av在线| 中国xxxxx高清免费看视频| 亚洲成人动漫在线观看| 国产一卡二卡四卡免费| 国产精品亚洲午夜一区二区三区| 成人免费视频一区| 国产亚洲精品欧洲在线观看| 亚洲日韩中文在线精品第一| 国产视频精品免费视频| 亚洲VA中文字幕无码毛片| 18禁止看的免费污网站| 国产亚洲精品成人AA片| 国产无遮挡吃胸膜奶免费看视频| 免费看黄网站在线看| 好看的电影网站亚洲一区| 午夜视频在线免费观看| 亚洲中文字幕一二三四区| 国产一区二区免费在线| 中文字幕乱码免费看电影| 亚洲日本乱码一区二区在线二产线 | 亚洲精品视频在线| 黄页网站免费观看| 搜日本一区二区三区免费高清视频| 久久影视国产亚洲| 91精品成人免费国产片| 羞羞漫画登录页面免费| 婷婷亚洲综合五月天小说| 成人毛片手机版免费看| 中国一级特黄的片子免费| 亚洲综合偷自成人网第页色| 亚洲av区一区二区三| 亚洲精品在线免费观看| 日本中文字幕免费看| 亚洲老熟女@TubeumTV|