Have We Found the First Moon outside the Solar System?

 

Scientists say they may have found the first moon outside our solar system.

Many planets are known to exist beyond our solar system. But there has been no confirmation¹ of a moon on the outside.

The possible moon appears considerably² larger than Earth and is 8,000 light years away. Astronomers³ say the object is about the size of the planet Neptune⁴. It orbits a planet that is similar in size to the large planet Jupiter.

Alex Teachey and David Kipping of Columbia University recently presented their findings.

The researchers studied 284 planets discovered by NASA’s Kepler Space Telescope. Only one planet, Kepler-1625b, held promise of a possible moon. That planet orbits the star Kepler-1625.

Last October, the researchers aimed the Hubble Space Telescope at the star to study the possibility of a moon nearby.

They were looking for momentary⁵ light decreases from the star. The planet itself blocks the light temporarily when it passes in front of Kepler-1625. A second lesser⁶ decrease could mean a moon was passing as well.

The astronomers observed such a sign about 3 ? hours after the planet passed the star.

The researchers also said that the planet passed more than an hour earlier than expected. They noted⁷ that a moon could cause the planet to have an unpredictable path. Kipping said that is how the Earth and moon would appear from far away. This planet — or exoplanet — is about the same distance from its star as Earth is from the sun.

For Teachey and Kipping, the best and simplest explanation is that Kepler-1625b has a moon.

The observation period, however, ended before they could see the moon complete its path. To confirm the existence of the moon, the astronomers hope to observe the star again next spring.

Their findings appeared in the publication Science Advances .

Teachey said the discovery of the first exomoon is, in his words, “an extraordinary claim and it requires extraordinary evidence.” He added, “We’re not cracking open champagne⁸ bottles just yet on this one.”

If it were an exomoon, it would be about 3 million kilometers from its own planet. The astronomers are also not sure how this possible exomoon might have formed, given its size.

Thomas Zurbuchen is an official with NASA’s space science programs. He said in a statement, “If confirmed, this finding could completely shake up our understanding of how moons are formed and what they can be made of.”

I’m Caty Weaver⁹.

Words in This Story

champagne - n. a French wine with bubbles and that people often drink to celebrate special occasions

1 confirmation   

n.证实，确认，批准

参考例句：

• We are waiting for confirmation of the news.我们正在等待证实那个消息。
• We need confirmation in writing before we can send your order out.给你们发送订购的货物之前，我们需要书面确认。

2 considerably   

adv.极大地；相当大地；在很大程度上

参考例句：

• The economic situation has changed considerably.经济形势已发生了相当大的变化。
• The gap has narrowed considerably.分歧大大缩小了。

3 astronomers   

n.天文学者，天文学家( astronomer的名词复数 )

参考例句：

• Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
• Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪，为什么只有土星有光环。 来自《简明英汉词典》

4 Neptune   

n.海王星

参考例句：

• Neptune is the furthest planet from the sun.海王星是离太阳最远的行星。
• Neptune turned out to be a dynamic,stormy world.海王星原来是个有生气、多风暴的世界。

5 momentary   

adj.片刻的，瞬息的；短暂的

参考例句：

• We are in momentary expectation of the arrival of you.我们无时无刻不在盼望你的到来。
• I caught a momentary glimpse of them.我瞥了他们一眼。

6 lesser   

adj.次要的，较小的；adv.较小地，较少地

参考例句：

• Kept some of the lesser players out.不让那些次要的球员参加联赛。
• She has also been affected,but to a lesser degree.她也受到波及，但程度较轻。

7 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

8 champagne   

n.香槟酒；微黄色

参考例句：

• There were two glasses of champagne on the tray.托盘里有两杯香槟酒。
• They sat there swilling champagne.他们坐在那里大喝香槟酒。

9 weaver   

n.织布工；编织者

参考例句：

• She was a fast weaver and the cloth was very good.她织布织得很快，而且布的质量很好。
• The eager weaver did not notice my confusion.热心的纺织工人没有注意到我的狼狈相。