| 查看: 1666 | 回复: 8 | |||
[交流]
Everyday News-Diamond Planet Orbits a Pulsar
|
Astronomers have discovered the densest extrasolar planet yet: A Jupiter-mass remnant of a carbon- and oxygen-rich star that measures no more than 55,000 kilometers across. The odd world, whose density is on average at least 23 grams per cubic centimeter (or about twice that of lead), is probably crystalline and possibly largely composed of ultradense diamond. The planet orbits its parent sun—a pulsar, or a rapidly-spinning neutron star that emits an intense beam of radio waves, dubbed PSR J1719-1438—once every 2 hours and 10 minutes, the researchers report online today in Science. The planet’s orbit measures about 600,000 kilometers across, only 50% more than the average distance from Earth to the moon. How such a dense planet formed is unclear, the researchers say, but it’s probably the crystalline vestige of a white dwarf star whose atmosphere was stripped away by the parent pulsar. Most of the pulsars that spin faster than once per 20 milliseconds are part of a binary star system, but about 30% have no companions whatsoever, the scientists note. Only one other rapidly-spinning pulsar is known to be orbited by Earth-mass planets—a sign that exotic planets such as this megadiamond are, like their Earthly counterparts, rare indeed. |
回复此楼» 猜你喜欢
售SCI一区T0P文章，我:8.O.55.1.O54,科目全,可伽急
已经有3人回复
-
售SCI一区文章，我:8O5.5.1.O5.4,科目全,可伽急
已经有3人回复
-
售SCI文章，我:8O.5.5.1O.54,科目全,可十急
已经有3人回复
-
售SCI一区T0P文章，我:8.O.55.1.O54,科目全,可伽急
已经有4人回复
-
售SCI一区T0P文章，我:8O.55.1.O.5.4,科目齐全,可+急
已经有5人回复
-
售一区SCI文章T0P，我:8O.551.O54,科目全,可十急
已经有4人回复
-
售SCI文章，我:8O.5.5.1O.54,科目全,可十急
已经有6人回复
-
售SCI一区T0P文章，我:8.O.55.1.O.5.4,科目全,可+急
已经有5人回复
-
售SCI一区文章，我:8.O.55.1.O.54,科目齐全,可伽急
已经有8人回复
-
售SCI一区T0P文章，我:8.O55.1.O.54,科目全,可十急
已经有6人回复
WG222
木虫 (正式写手)
- 应助: 18 (小学生)
- 贵宾: 0.02
- 金币: 2160.4
- 红花: 4
- 沙发: 4
- 帖子: 379
- 在线: 169.8小时
- 虫号: 454642
- 注册: 2007-11-10
- 性别: GG
- 专业: 污染控制化学
2楼2011-09-06 18:50:48
★
小木虫(金币+0.2):抢了个小板凳，给个红包
小木虫(金币+0.2):抢了个小板凳，给个红包
  |
3楼2011-09-06 18:53:33
4楼2011-09-06 19:10:20
sgh_119
至尊木虫 (职业作家)
- ESEPI: 1
- 应助: 0 (幼儿园)
- 贵宾: 0.045
- 金币: 15120.1
- 红花: 13
- 沙发: 59
- 帖子: 4989
- 在线: 648.4小时
- 虫号: 614182
- 注册: 2008-09-27
- 性别: GG
- 专业: 绿色有机化学
5楼2011-09-06 19:28:23
6楼2011-09-06 23:54:14
7楼2011-09-07 00:37:23
yinjuanchen
铁杆木虫 (著名写手)
- 应助: 1 (幼儿园)
- 金币: 5909.8
- 散金: 397
- 红花: 23
- 帖子: 2881
- 在线: 434.7小时
- 虫号: 961438
- 注册: 2010-03-04
- 性别: MM
- 专业: 无机材料化学
8楼2011-09-07 07:24:38
 |
9楼2011-09-07 18:23:20
40