Forget Earth-like 惑星s: 外国人 life may be lurking in the clouds of 冷淡な 'failed 星／主役にするs'

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Finding 惑星s with the 権利 肉親，親類d of atmosphere to support 外国人 life is something 天文学者s are 絶えず 努力する／競うing に向かって.

研究員s have now 設立する another 可能性のある habitat that could harbour ET in the clouds of 冷淡な 惑星-星／主役にする hybrids known as 'brown dwarfs'.

A brown dwarf is a type of 'failed 星／主役にする' that is sized somewhere between a 巨大（な） 惑星 and a small 星／主役にする.?

The 天文学者s 設立する that the 圧力 and 気温 設立する in brown dwarfs' upper atmosphere is very 類似の to Earth's, 示唆するing it could be the perfect 位置／汚点／見つけ出す for 外国人 microbes to grow.

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University of Edinburgh 天文学者s have 設立する that the 圧力 and 気温 設立する in brown dwarfs' (artist's impression pictured) is very 類似の to Earth's. They say this means it could be a good place to look for 外国人 life

The 研究員s 見積（る） that one billion brown dwarfs 存在する in our 乳の Way 星雲, with plenty 比較して の近くに by at around 32 light years away.

Previous 熟考する／考慮するs have argued that brown dwarfs 持つ／拘留する many of the 重要な 成分s for life, 含むing 炭素, hydrogen, 窒素 and oxygen.

The finding may mean that science must abandon its idea that extraterrestrial life needs land and water to 生き残る.

Brown dwarfs are smaller than 星／主役にするs, but more 大規模な than 巨大（な） 惑星s.?

They could help shed light on how different 惑星s form their atmospheres - but because they come in a 抱擁する variety of 形態／調整s and sizes, exactl y how they themselves form has, until recently, been difficult to understand.?

Brown dwarfs are mostly made up of large plumes of 渦巻くing gas, and a team of planetary scientists from the University of Edinburgh 調査／捜査するd one such 反対する called?WISE 0855-0714.

This brown dwarf was discovered?in 2013 and sits around 7 million light years?away from Earth.

The gaseous 団体／死体 is of particular 利益／興味 to sc ientists looking for extraterrestrial life because it is colder than most brown dwarfs, giving 比較して 穏やかな 気温s that are 類似の to Earth's.

WHAT IS A BROWN DWARF??

Photo taken by the Hubble space telescope in 2006 shows brown dwarfs as faint red 星／主役にするs

Brown dwarfs are 反対するs that are not 大規模な enough to 支える hydrogen fusion reactions in their 核心s, unlike main-sequence 星／主役にするs.

They have a 集まり of between the heaviest gas 巨大（な）s and the lightest 星／主役にするs, with an upper 限界 around 75 to 80 Jupiter 集まりs.

Brow n dwarfs heavier than about 13 Jupiter 集まりs are thought to fuse deuterium, or 激しい hydrogen, and those above 65 fuse lithium 同様に.

The defining differences between very low-集まり brown dwarfs and gas 巨大（な）s are still 審議d between scientists.

Some think it is based on 形式 while others think it is based on the physics of the 内部の.

Part of the 審議 also 関心s whether 'brown dwarfs' must, by 鮮明度／定義, have experienced fusion at some point in their history.

宣伝

The team used 計算／見積りs from 公式文書，認めるd scientist Carl Sagan, 初めは ーするつもりであるd to 調査／捜査する the 可能性 of life on Jupiter.

As Jupiter is a gaseous 巨大（な）, these 計算／見積りs took into account that the organisms would not need solid ground to 生き残る.

'You don't やむを得ず need to have a terrestrial 惑星 with a surface,' co-研究員 and planetary scientist Jack Yates told Science.

The 研究員s also considered the nature of 浮遊生物 living on Earth to 診察する whether 類似の forms of life could 存在する within the gaseous clouds of a brown dwarf.

'We argue that an atmosphere sitting above a 潜在的に uninhabitable planetary surface may be 冷静な／正味の enough to 支える life,' the 研究員s say in their paper.

Brown dwarfs are 反対するs that are not 大規模な enough to 支える hydrogen fusion reactions in their 核心s, unlike main-sequence 星／主役にするs. They have a 集まり of between the heaviest gas 巨大（な）s and the lightest 星／主役にするs, with an upper 限界 around 75 to 80 Jupiter 集まりs

'By doing this, we define an atmospheric habitable zone (AHZ).'

With one billion brown dwarfs to 調査／捜査する in our 星雲 alone, the 研究員s 示唆する that there is plenty more searching to be done in the 追求（する），探索（する） to find extraterrestrial life.

The idea remains hypothetical for now, though, and work must go into 証明するing the 存在 of any brown dwarf microbes in 未来.

The finding comes after Washington-based 研究員s 明らかにする／漏らすd brown dwarfs' 可能性のある value in the search for 外国人 life earlier this year.

Dr Jacqueline Faherty from the Carnegie 会・原則 for Science in Washington recently 調査するd さまざまな 所有物／資産／財産s of 152 嫌疑者，容疑者／疑うd young brown dwarfs.

She 設立する atmospheric 所有物／資産／財産s could be behind much of their differences.

This could shed light on the exact form of brown dwarfs.?

The work, published by the Astroph ysical 定期刊行物 補足（する） series, could also help us to understand the atmospheres of 惑星s outside the solar system.

If a 惑星 is in a 星／主役にする's 'habitable zone' - an area around a 星／主役にする in which an 軌道ing 惑星's surface could 持つ／拘留する liquid water - it could host 外国人 life. Artist's illustration of an Earth-sized 惑星 in the habitable zone of its host 星／主役にする, pictured

Understanding the atmospheres of brown dwarfs will help us to learn more about the atmospheres of 惑星s that were formed around the same 星／主役にするs as they were.

This will help 天文学者s work out whether 惑星s have an atmosphere 類似の to Earth's.< /p>

Brown dwarfs 持つ／拘留する 約束 for explaining not just planetary 進化, but also how 星／主役にするs form.

The 反対するs are tougher to 位置／汚点／見つけ出す than more-大規模な and brighter 星／主役にするs, but they vastly より数が多い 星／主役にするs like our sun.

'Brown dwarfs are far easier to 熟考する／考慮する than 惑星s, because they aren't 圧倒するd by the brightness of a host 星／主役にする,' Dr Faherty explained.?

By looking at the 所有物／資産／財産s of hundreds of brown dwarfs, Dr Faherty and her team showed the 範囲 of 所有物／資産／財産s was not brought about by difference in age or 化学製品 composition.?

'I consider these young brown dwarfs to be siblings of 巨大（な） exoplanets. As の近くに family members, we can use them to 調査／捜査する how the planetary 高齢化 過程 作品,' Dr Faherty said.