Earth-sized Planet Discovered in Alpha Centauri System
by VOA News
Astronomers in Europe have discovered the first-ever planet with a mass similar to Earth and orbiting a star like the Sun. And, ___1___ galactic terms, it’s right next door.
The unnamed planet is in the Alpha Centauri star system, the nearest system to Earth, according to the European Southern Observatory (ESO).
“This result ___2___ a major step towards the detection of a twin Earth in the immediatevicinity of the Sun. We live in exciting times!” said Xavier Dumusque of the Geneva Observatory and Centro de Astrofisica da Universidade do Porto in Portugal in a ___3___ release on the discovery.
___4___ the excitement, scientists say the new planet’s climate likely would not be nearly as hospitable as Earth.
“Its orbit is very close to its star and it must be much too hot for life as we know it,” said Stéphane Udry of the Geneva Observatory and a co-author of the paper about the discovery.
The ___5___ planet orbits a mere six million kilometers from its star, much closer than Mercury is to the Sun.
Alpha Centauri is the nearest stellar system to the earth’s solar system at only 4.3 light-years, making it one of the brightest objects in the southern skies. It is actually a three-star system ___6___ of two stars similar to the Sun orbiting close to each other, Alpha Centauri A and B, and a more distant and faint red star known as Proxima Centauri.
By detecting tiny wobbles in the motion of Alpha Centauri B, astronomers were able to determine the presence of the planet. The planet’s ___7___ on the star causes it to move no more than 51 centimeters per second, or about the speed of a baby crawling.
In 1995, the same team ___8___ the first exoplanet around a Sun-like star. There have been more than 800 confirmed discoveries of exoplanets using the same wobble method ___9___ then, according to the ESO, but scientists have yet to find a planet of Earth’s size orbiting at a habitable distance from its star.
Vocabulary
- orbit v. to travel in a curved path around a much larger object
- vicinity n. the area around a particular place
- hospitable adj. used for describing an environment in which things can grow
- stellar adj. relating to the stars
- wobble v. to move unsteadily from side to side
Cloze
1. (A) by (B) with (C) in (D) of
2. (A) represented (B) represents (C) has represented (D) representing
3. (A) reporter (B) press (C) record (D) film
4. (A) Despite (B) In spite (C) Although (D) Since
5. (A) discover newly (B)discover new (C) new discovered (D) newly discovered
6. (A) made up (B) made for (C) made off (D) made over
7. (A) effect (B) affect (C) efficiency (D) affection
8. (A) was discovered (B) discover (C) discovered (D) had discovered
9. (A) by (B) for (C) from (D) since
Source: http://www.voanews.com/content/european_astronomers_discover_new_planet/1528161.html
Answers: C B B A D A A C D
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