科學(xué)60秒:日薄西山,也不離不棄
來源:滬江聽寫酷
2011-06-22 10:00
Astronomers have already discovered hundreds of exoplanets. But ____1____ the new kid. Which is orbiting a kind of star that models say it shouldn’t.
Researchers found the exoplanet while looking at the star HIP 13044 — or Sergio, for Star of Extra-Galactic Origin. It’s in what once was a separate galaxy, which the Milky Way ____2____ billions of years ago.
The scientists saw Sergio wobbling due to the gravitational tug of a Jupiter-sized gas planet, which the scientists dubbed Sergio Junior. They detail their find in the journal Science.
You don’t ordinarily find planets ____3____ a star like Sergio. First, it's really old — past the Red Giant phase, when stars balloon in size and ____4____ planets in close orbits. And planets tend to form around metal-rich stars, like our Sun. But Sergio has only one percent the metal content of our Sun. That doesn't ____5____ one widely accepted model of planetary formation.
The Sergios may offer a glimpse of the future of our own planetary system — in about five billion years. We hope to be back then with an update.
【視聽版科學(xué)小組榮譽(yù)出品】
Researchers found the exoplanet while looking at the star HIP 13044 — or Sergio, for Star of Extra-Galactic Origin. It’s in what once was a separate galaxy, which the Milky Way ____2____ billions of years ago.
The scientists saw Sergio wobbling due to the gravitational tug of a Jupiter-sized gas planet, which the scientists dubbed Sergio Junior. They detail their find in the journal Science.
You don’t ordinarily find planets ____3____ a star like Sergio. First, it's really old — past the Red Giant phase, when stars balloon in size and ____4____ planets in close orbits. And planets tend to form around metal-rich stars, like our Sun. But Sergio has only one percent the metal content of our Sun. That doesn't ____5____ one widely accepted model of planetary formation.
The Sergios may offer a glimpse of the future of our own planetary system — in about five billion years. We hope to be back then with an update.
【視聽版科學(xué)小組榮譽(yù)出品】
make way for
gobbled up
hanging around
swallow up
jibe with
發(fā)現(xiàn)有行星繞著不同以往類型的恒星轉(zhuǎn)
天文學(xué)家已發(fā)現(xiàn)了數(shù)以百計(jì)的太陽系外行星。但是,現(xiàn)在該給新成員騰讓地方了,這顆行星圍繞著某顆恒星旋轉(zhuǎn),用事實(shí)證明了傳統(tǒng)理論可不完全正確。
研究人員是在研究HIP 13044恒星的時(shí)候發(fā)現(xiàn)了這顆太陽系外行星。恒星HIP 13044 又名Sergio(塞爾吉奧),取“在銀河系外起源的恒星”之意。它在曾經(jīng)是一個(gè)獨(dú)立的星系,在幾十億年前被銀河系吞并了。
科學(xué)家們觀察到Sergio(塞爾吉奧)由于受到一個(gè)木星大小的氣態(tài)行星造成的引力而變得不穩(wěn)定,科學(xué)家將這顆氣態(tài)行星戲稱為Sergio(塞爾吉奧)二世。他們?cè)凇犊茖W(xué)》雜志上詳細(xì)敘述了自己的發(fā)現(xiàn)。
通常,你不會(huì)在如Sergio(塞爾吉奧)這樣的恒星周圍發(fā)現(xiàn)行星。首先,它非常非常老了——它經(jīng)歷過紅巨星階段,這一階段的恒星會(huì)急劇膨脹,吞噬在臨近軌道運(yùn)行的行星。而行星往往會(huì)在富含金屬的恒星——好似我們的太陽這種恒星——周圍形成??蒘ergio(塞爾吉奧)的金屬含量只有太陽的百分之一。這種情況跟一個(gè)被廣泛接受的行星形成模型并不一致。
Sergios(塞爾吉奧)或許可以讓我們一窺自己的行星系統(tǒng)——大約50億年后的未來。到那時(shí)候,我們希望還能回來再更新
節(jié)目給大家。