Latest News:  
Beijing   Sunny/Cloudy    2 / -4   City Forecast

People's Daily Online>>Science

NASA finds Earth-size planets outside solar system

(Xinhua)

13:12, December 21, 2011

This handout image by NASA on Dec. 20, 2011 shows an artist's conception illustrating Kepler-20e. (Xinhua/NASA/Ames/JPL-Caltech)

NASA's Kepler mission has discovered the first Earth-size planets orbiting a sun-like star outside our solar system. The planets, called Kepler-20e and Kepler-20f, are too close to their star to be in the so-called habitable zone where liquid water could exist on a planet's surface, but they are the smallest exoplanets ever confirmed around a star like our sun. Kepler-20e is the first planet smaller than the Earth discovered to orbit a star other than the sun. A year on Kepler-20e only lasts 6 days, as it is much closer to its host star than the Earth is to the sun. The temperature at the surface of the planet, around 1400 degrees Fahrenheit, is much to hot to support life, as we know it. Kepler-20e is likely to be entirely rocky and without an atmosphere. The planet is tidally locked, always showing the same side to its host star, as the moon to the Earth, and could have large temperature differences between its permanent night and day sides. Astronomers think that the planet is likely to be geologically active, due to its own formation process and the strong gravitational interactions with its host star. In this artistic depiction, the planet is represented with active volcanoes on both the night and day sides.

【1】 【2】 【3】

 
 
 
 
We Recommend
 
 
 

Email|Print|Comments(Editor:雪萌)

Leave your comment0 comments

  1. Name

  

Selections for you


  1. Liyuan Garden in Wuxi

  2. APF emergency rescue team established

  3. Beautiful icefalls along Yellow River

  4. Japan picks F-35 as next-generation fighter

Most Popular

Opinions

  1. To whom does Pacific Century belong?
  2. US media hypes 'cyber Cold War'
  3. Farmers find city life unfair: report
  4. Soccer bribe trials chance to clean up sport's legacy
  5. Euro zone makes progress in systemic reforms
  6. Weibo regulations a step on the right path
  7. Real names on Weibo points to progress
  8. China's foreign policy not a matter of tough vs. soft
  9. Growth moderation not "bad thing" for China
  10. Risks behind India's military buildup

What's happening in China

Talented farmers start own calligraphy business

  1. Baidu Inc expands into mobile Internet market
  2. Judicial decision to protect intellectual property
  3. Oil pipeline leak may take months to fix
  4. Ex-railway official's US home cost over 7m yuan
  5. New microblog rules confound companies

PD Online Data

  1. Legends of Mid-Autumn Festival
  2. Modern Mooncakes
  3. Regional Varieties of Mooncakes
  4. Traditional Mooncakes
  5. History of Mooncakes