| ²é¿´: 717 | »Ø¸´: 4 | |||
ColonelGгæ (ÕýʽдÊÖ)
|
[½»Á÷]
Two new Earth-sized exoplanets discovered
|
|
Hunting for habitable worlds, NASA¡¯s Kepler space telescope has unveiled two new planets, some 950 light-years away, that are the smallest yet detected, and the closest in size to Earth. In a paper published this week in Nature, scientists from MIT and elsewhere report that the planets ¡ª one just about Earth¡¯s size, and the other a bit smaller ¡ª likely have rocky compositions, similar to Earth, and orbit a star much like the sun. But that¡¯s where the similarities end. Compared with Earth¡¯s leisurely 365-day orbit, the new planets practically whiz around their star in a matter of days or weeks. Their tight circuits, closer even than Mercury¡¯s orbit around our sun, make the planets extremely hot ¡ª likely too hot to sustain life. While either planet is far from Earth¡¯s twin, scientists say the discovery is a technological milestone. ¡°For the Kepler space telescope, it¡¯s extremely significant, because it proves we can reach down to Earth¡¯s size,¡± says co-author Sara Seager, the Ellen Swallow Richards Professor of Planetary Science and Professor of Physics at MIT. ¡°It¡¯s a massive accomplishment just to find anything at all like this.¡± The new planets, which orbit the star Kepler 20, are part of a five-planet system, and have been named Kepler 20e and Kepler 20f. ¡°This will hopefully open the floodgates to discovering more of these Earth-sized and sub-Earth-sized planets,¡± says co-author Leslie Rogers, a physics graduate student at MIT. ¡°Then we¡¯ll be able to determine some sort of context for how common are habitable Earth-sized planets.¡± |
» ²ÂÄãϲ»¶
¡¾¿¼Ñе÷¼Á¡¿»¯Ñ§×¨Òµ 281·Ö£¬Ò»Ö¾Ô¸ËÄ´¨´óѧ£¬³ÏÐÄÇóµ÷¼Á
ÒѾÓÐ5È˻ظ´
ÄÜÔ´²ÄÁÏ»¯Ñ§¿ÎÌâ×éÕÐÊÕ˶ʿÑо¿Éú8-10Ãû
ÒѾÓÐ12È˻ظ´
288Çóµ÷¼Á
ÒѾÓÐ10È˻ظ´
0703»¯Ñ§µ÷¼Á
ÒѾÓÐ4È˻ظ´
ÕÐÊÕµ÷¼Á˶ʿ
ÒѾÓÐ10È˻ظ´
271²ÄÁϹ¤³ÌÇóµ÷¼Á
ÒѾÓÐ6È˻ظ´
²ÄÁÏר˶274Ò»Ö¾Ô¸ÉÂÎ÷ʦ·¶´óѧÇóµ÷¼Á
ÒѾÓÐ8È˻ظ´
Ò»Ö¾Ô¸Î人Àí¹¤²ÄÁϹ¤³Ìר˶µ÷¼Á
ÒѾÓÐ4È˻ظ´
085601²ÄÁϹ¤³Ìר˶Çóµ÷¼Á
ÒѾÓÐ10È˻ظ´
321Çóµ÷¼Á
ÒѾÓÐ8È˻ظ´
¡ï
Сľ³æ(ɳ·¢+1£¬½ð±Ò+0.5):¹§Ï²ÇÀ¸öɳ·¢£¬ÔÙ¸ø¸öºì°ü
Сľ³æ(ɳ·¢+1£¬½ð±Ò+0.5):¹§Ï²ÇÀ¸öɳ·¢£¬ÔÙ¸ø¸öºì°ü
|
2Â¥2011-12-21 20:15:47
bai123
ÈÙÓþ°æÖ÷ (ÎÄ̳¾«Ó¢)
´ó°×öè
-

ר¼Ò¾Ñé: +55 - ESEPI: 1
- Ó¦Öú: 576 (²©Ê¿)
- ¹ó±ö: 2.134
- ½ð±Ò: 29136.5
- É¢½ð: 20171
- ºì»¨: 172
- ɳ·¢: 3286
- Ìû×Ó: 37666
- ÔÚÏß: 2450.2Сʱ
- ³æºÅ: 1157707
- ×¢²á: 2010-11-28
- רҵ: Óлú¸ß·Ö×Ó¹¦ÄܲÄÁÏ

3Â¥2011-12-21 20:21:03
С¶¡×Ó
ľ³æ (ÖªÃû×÷¼Ò)
- ESEPI: 36
- Ó¦Öú: 7 (Ó×¶ùÔ°)
- ¹ó±ö: 1.015
- ½ð±Ò: 756
- É¢½ð: 8187
- ºì»¨: 122
- ɳ·¢: 50
- Ìû×Ó: 9631
- ÔÚÏß: 860.7Сʱ
- ³æºÅ: 1053762
- ×¢²á: 2010-07-08
- ÐÔ±ð: MM
- רҵ: ¼ÆËã»úÓ¦Óü¼Êõ

4Â¥2011-12-22 13:57:53
ColonelG
гæ (ÕýʽдÊÖ)
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 532.9
- É¢½ð: 88
- ºì»¨: 4
- Ìû×Ó: 797
- ÔÚÏß: 178.1Сʱ
- ³æºÅ: 935913
- ×¢²á: 2010-01-01
- ÐÔ±ð: GG
- רҵ: »¯¹¤ÏµÍ³¹¤³Ì
5Â¥2011-12-22 14:07:25













»Ø¸´´ËÂ¥
no one more£¿ 