Two other large telescopes besides E-ELT, of 27 metres and 30 metres diameter, are under construction and planned. But some suggest the first of these, the Giant Magellan Telescope, also in Chile, is not well suited to the use of a coronagraph, and the second, the Thirty Metre Telescope, is planned at the moment for Hawaii, which is in the northern hemisphere. Proxima Centauri is in the southern skies, and therefore not so easy to study from north of the equator. 

besides：の他に
equator：赤道

There may, just possibly, be a short cut. Though Proxima Centauri b was discovered by the radial-velocity technique, there is about a 1.5% chance that it might also be detectable by the transit technique. This would require Earth to sit in the same plane as the planet and its star, so that, seen from Earth, it crosses the face of its parent and thus slightly dims it. Various southern-hemisphere telescopes are already looking for the 0.5% dimmings of Proxima Centauri’s brightness which would be observed if Proxima Centauri b were transiting. If it is, then it will be possible to study its spectrum by subtracting the star’s spectrum when the planet is hidden behind it from the spectrum measured during a transit. That would reveal the chemical composition of its atmosphere, if it has one—which might, in turn, give a clue as to whether it harbours life. 

short cut：近道・手っ取り早い方法
radial-velocity：視線速度 
transit technique：Transit Timing Variations (TTV)法は,トランジット惑星のトランジット周期の変動を観測することでその摂動源となる別の惑星の存在をとらえる惑星検出法である.TTV 法は最近手法が確立 された比較的新しい惑星検出法であり,今後この手法を用いた新たな系外惑星研究の展開が期待さ れている.
dims：薄暗くする
transit：(天体の)通過〘天体が太陽子午線望遠鏡などを横切ること〙.
composition：構造
harbours：潜む

Rainbow bridges
Life on Earth leaves a sign of its existence in the atmosphere, in the form of oxygen. This is produced by plants and it is such a reactive chemical that if their photosynthesis stopped it would disappear rapidly from the air. Free oxygen in Proxima Centauri b’s atmosphere would therefore get a lot of people excited—but possibly without justification, for there are ways (such as the dissociation of water by ultraviolet light) to put oxygen into atmospheres abiotically. A stronger indicator of life would be finding both oxygen and molecules associated with biology that cannot long persist in its presence, and must thus be produced continuously. 

photosynthesis：光合成
dissociation：分離
ultraviolet：紫外線の
abiotically：生命のない
molecules：分子
biology：生態・生物学

On Earth nitrous oxide and methane fit this bill, though these molecules are present in amounts much too low to be seen light-years away. But David , a colleague of Dr Barnes at the University of Washington, points out that there are models of planetary atmospheres which allow methane to build up quite a lot on a planet like Proxima Centauri b. If spectra showed methane and oxygen together, the likelihood of life on Proxima Centauri b would rise dramatically. 

nitrous：亜酸化窒素
bill：条件をちょうど満たす
light-years：光年

Another way to look for life on Proxima Centauri b would be to search for radio signals. Life in general does not generate radiation at radio frequencies. But intelligent life does—at least it does on Earth. And that Earth-bound life also puts a tiny bit of effort into looking for such emissions from elsewhere, an endeavour known as the search for extraterrestrial intelligence, or SETI. There have been SETI studies of Proxima Centauri in past decades, but they have not been particularly sensitive. If the inhabitants of Proxima Centauri b were beaming powerful transmissions at Earth all day and night they would have been heard; if they were merely using radio for their own ends, in the way that broadcasters and radar systems do on Earth, they would not. 

radio：電波
radiation：発散
extraterrestrial：地球外の
for their own ends：彼らの目的のために利用する

Now, though, a big new SETI project bankrolled by Yuri Milner, a Russian billionaire with a taste for things interstellar, is collaborating with the Parkes radio telescope in Australia and the Meerkat radio array in South Africa. According to Dan Werthimer of the University of California, Berkeley, who works on Mr Milner’s programme, Proxima Centauri will now be getting a lot more attention. 

bankrolled：資金援助をする
interstellar：恒星間の

火曜日。今日はこれまで。Proxima Centauriの恒星に生物がいるのかのいろいろな調査の方法を解説している。望遠鏡だけではなく、トランジット法とか電波とか、化学物質の分析とかの方法で生命の存在を調べようとしている。彼らが熱狂していることは想像に難くない。

昨日の朝は朝会があったが、そのあとは愚妻と一緒に慈恵医大に行った。ひどく血圧が低かったようだ。午後は事務所の引っ越しの事務作業をしていて、夜にようやく少しだけ仕事ができた。今日は昼はいつもの会食だがそれ以外は明日の研修の準備ができる。今後の予定も見直さないといけない。資料がどうも似たようなものが多いので、考え直さないといけない。ではまた明日。