航空航天港

 找回密码
 注册会员

QQ登录

只需一步,快速开始

查看: 12565|回复: 109
收起左侧

Kepler/开普勒望远镜寻找另一个地球:2014年候选者更新

[复制链接]
hkhtg090201 发表于 2011-1-29 14:14 | 显示全部楼层 |阅读模式

对本站感兴趣的话,马上注册成为会员吧,我们将为你提供更专业的资讯和服务,欢迎您的加入!

您需要 登录 才可以下载或查看,没有帐号?注册会员

x
本帖最后由 hkhtg090201 于 2015-12-13 13:35 编辑


本贴对应于航天版的:

北京时间3月7日,Kepler望远镜将从卡纳维拉尔角空军基地发射
http://www.9ifly.cn/thread-850-1-1.html


而下面的帖子作为“所有”的 系外行星发现跟踪帖子.
http://www.9ifly.cn/thread-2017-1-1.html
 楼主| hkhtg090201 发表于 2011-1-29 14:15 | 显示全部楼层
有望找到更多行星.
Kepler Has Found More Planets
By Keith Cowing on January 27, 2011 1:23 PM

NASA To Announce New Planetary Discoveries by Kepler

"NASA will host a news briefing at 1 p.m. EST, Wednesday, Feb. 2, to announce the Kepler mission's latest findings about planets outside our solar system. The briefing will be held in the NASA Headquarters auditorium at 300 E St S.W. in Washington and carried live on NASA Television and the agency's website."
 楼主| hkhtg090201 发表于 2011-2-2 15:57 | 显示全部楼层
本帖最后由 hkhtg090201 于 2011-2-2 16:46 编辑

采访:
Hunting for Earth-like Alien Planets: Q & A with Astronomer Geoff Marcy

Published February 01, 2011
| Space.com

Geoff Marcy has had a hand in discovering more alien planets than anyone else.

Since astronomers discovered the first planet beyond our own solar system back in 1992, they've been on somewhat of a roll — the tally now tops 500.

And the finds are about to ramp up dramatically. Today (Feb. 1), NASA's planet-hunting Kepler mission will make much of its data public. A press conference will follow tomorrow, during which researchers are expected to announce intriguing new information about many more possible alien planets.

Humanity thus appears poised to enter a productive new era in the study of alien worlds. One man leading the charge is Geoff Marcy, an astronomer at the University of California, Berkeley, and a Kepler co-investigator.

Marcy has had a hand in finding more alien planets than anyone else. He helped spot 70 of the first 100. He also found the first multi-planet system around a sun-like star, and he discovered the first planet that transits — or passes in front of — its star from our perspective on Earth.

SPACE.com caught up with Marcy last month in Seattle, at the winter meeting of the American Astronomical Society, to chat about the accelerating pace of planet discovery, what we still don't know about alien worlds and whether there might be intelligent life elsewhere in the universe.


问:是什么导致近来系外行星被大量发现,是仪器更好,还是技术更好?
SPACE.com: What has led to the recent explosion in alien planet discoveries? Is it primarily better instrumentation, or better techniques?
答:是人。
Marcy: Well, let me give you a different vantage point. There is a bunch of astronomers who've been working really hard, and they're really innovative, pushing on the frontier technically, pushing on the frontier in terms of the science. And basically burning the midnight oil, essentially literally. I'm giving you the human component of all of this, because sometimes you don't get to see it.

What sometimes gets lost in the shuffle when a nice result shows up on all of the Web pages and the newspapers around the world — what you don't realize is to get that result meant that five or 10 people were burning that midnight oil, trimming the errors down to the point that the Earth-size planets are detectable.

It's easy to dismiss the discoveries as, "Oh, it's new computers, or it's new optics." These things happen because amazing people dream and then put their dreams into perspiration-dripping action.

SPACE.com: So if we were to have this conversation in 20 years, where do you think the total exoplanet count would stand?

Marcy: Honestly, Kepler's so good that it's hard to beat it. It gets the numbers. Kepler's going to find thousands. There's going to be another follow-up to Kepler, either from Europe or the U.S. or both. They'll find thousands.

I bet by 2020, there'll be 10,000 planets, and by 2030 there might be another 20,000 or 30,000 more planets. [Gallery: The Strangest Alien Planets]

SPACE.com: Will this discovery arc we're on now continue to go up exponentially, or will it plateau?

Marcy: It'll plateau, because you can't do much better than Kepler. But let's be fair here. It's not the number of planets we care about; it's the quality. We want the Earth-size. We want planets in the habitable zone, and ultimately planets that are sending little radio signals to us for some reason or another.

SPACE.com: You've said that, with exoplanets, theory has really struck out. What are some of the things that we thought we knew, but it turns out were totally wrong about?

Marcy: Well, the first thing — I go back to 1996. No one wants to talk about this, because it's so embarrassing. The reason that as a community we struggled to find the first hot Jupiters isn't because we didn't have the technology. It's because the theorists led us astray. I'm speaking slightly jokingly, but not really.

There were theorists who said, "Look at our solar system. Of course the small, rocky planets are close in. The host star burned off the gases, so you're left with rocky planets. And look at the giant planets like Jupiter and Saturn — they had to form farther out, because it's colder, and the gases can gravitationally stick to the planets. Therefore, all planetary systems will have the following architecture: There will be an inner planet. The second planet out will be named Venus. The third planet out will have great lattes." I mean, it was just silly.

SPACE.com: And that's based on a sample size of one.

Marcy: It would be like trying to characterize human psychology by going to one distant Indonesian island and interviewing one person, and thinking that that gave you the full range of human psychology. And in 1996, there were papers where they said, Jupiter-sized planets, Saturn-sized planets, will all orbit far from their host star. Well, that of course tells you what to look for. If you write a proposal to try to find anything else, you're flying in the face of wisdom.

And we know now, of course, how near-sighted that was, how parochial that was.

SPACE.com: So do you think we are starting to get a handle on exoplanets now?

Marcy: I think so. We're always a little too confident, so I would hate to say, "Go home, we're all done." We do have these planets we're finding with Doppler work, and now with Kepler, that are five times the size of Earth, three times the size of Earth, 1.4 times the size of the Earth. And I don't think we really know how they formed.

Even the one we announced [the rocky, nearly Earth-size Kepler-10b], there are two main ways it might've formed. It might've formed like the Earth, or it might have formed like Uranus but it got so close to the host star that the gases and the water got evaporated away and left a bare, rocky core remnant.



SPACE.com: What are some of the biggest mysteries that are left?

Marcy: There's one huge one that nobody really wants to talk about. It's the age-old question: Are Earth-like planets common? We know they're out there for sure. I mean, there's too many stars. But there's two parts to the question. What do you mean by "Earth-like?" And then, how common are they?

Basically, we know what we want for Earth-like, so we shouldn't beat around the bush: We would love to know whether there are planets suitable for life as we know it.

And those Earth-like properties are a little bit mysterious, but we have some ideas. You want water in liquid form, you want stable temperatures over the course of millions, preferably billions, of years so that Darwinian evolution can get a good toehold.

You probably want a moon to stabilize the spin axis. You probably want a Jupiter to sweep up the debris. You probably want a stable ocean for a long enough time that it can serve as the solvent for biochemistry.

So that's probably what we mean by "Earth-like." But how common they are, we just don't know.

SPACE.com: Your research suggests that smaller planets may be pretty common — that nearly one in four nearby sun-like stars could host a roughly Earth-size planet.

Marcy: Yeah. But here's the sleeper idea that no one wants to talk about: Because Earth-size planets are so much smaller than the Jupiters, Saturns, Uranuses and Neptunes, and we now know that planets often get thrust into eccentric and misaligned orbits, the Earths are like the Volkswagens on a highway full of 18-wheelers.

The vulnerable planets are the small ones. And so to the extent that planetary systems undergo a billiards era — the Earth would be like putting a small marble on a pool table of 15 billiard balls. As you break, the little planets are going to be the ones slingshot right out of the solar system pool table.

SPACE.com: It's one thing to say they can form. But to say that they'll actually stick around long enough — that's a totally different question.

Marcy: Yeah. And I think they'll form. It's hard to imagine they wouldn't. If you make Jupiters, why wouldn't you make Earth-size planets? But the Earths — and maybe the Volkswagen is giving it too much credit. It's an 18-wheeler and a tricycle. Earth is a tricycle on Highway 5 running up and down the Pacific Coast.

And you don't even have to hit the tricycle. You just have to come close enough that gravity slingshots the poor tricycle right out of the system. So it's possible that Earth-like planets form, they get thrown out into the cold darkness of the galaxy and they have no chance of starting — never mind sustaining — life, because it's too cold out there.

And that's possible. We might be rare.

And by the way: Where are the SETI [search for extraterrestrial intelligence] signals? There is a non-detection that's like the elephant in the room. Forty years of Frank Drake and Carl Sagan looking for SETI signals, and we have precisely zero to show for it. So there's an indication — not definitive — that maybe the Earth is more precious than we had thought.

MW: Our solar system is so young, compared to the universe. And the universe is so big. So there's been lots of time and opportunity for advanced civilizations to get started, and to try to contact us. Some people think that the fact that we seemingly haven't been contacted means that we may well bealone in the universe.

Marcy: Well, you have to fold it in. The absence of an intelligent radio or television wave from any advanced civilization represents one indication, not a proof, that maybe habitable planets that sustain Darwinian evolution for a billion years —maybe they're rare. Maybe.

SPACE.com: What do you reckon? Do you have a gut feeling about this?

Marcy: I do. If I had to bet — and this is now beyond science — I would say that intelligent, technological critters are rare in the Milky Way galaxy. The evidence mounts. We Homo sapiens didn't arise until some quirk of environment on the East African savannah — so quirky that the hominid paleontologists still can't tell us why the australopithecines somehow evolved big brains and had dexterity that could play piano concertos, and things that make no real honest sense in terms of Darwinian evolution.

Why the high chaparral on the East African savannah would've led to a Tchaikovsky piano concerto, never mind the ability to build rocket ships — there's no evolutionary driver that the australopithecines suffered from that leads to rocket ships. And so that — and the fact that we had to wait four billion years without humans. Four billion years?

SPACE.com: Yes, it took four billion years to get there.

Marcy: Since the Cambrian explosion, we had hundreds of millions of years of multi-cellular, advanced life in which, guess what happened with brain size? Nothing.

You know the greatest species ever to roam the Earth? The dinosaurs — every kid knows this. And why? Well, because for 100 million years, the dinosaurs roamed the Earth. There were big ones, there were small ones. Every generation of baby dinosaurs had to outcompete all of the other dinosaurs. And you would think after 100 million years, each generation of baby dinosaur that was a little smarter would have out-survived the others and thereby slowly but surely increased dinosaur cranial size.

The reality from the paleontological record? Dinosaurs had the brains of chickens, and never got bigger. It shows that braininess is not a primary driver in evolution. We humans came across braininess because of something weird that happened on the East African savannah. And we can't imagine whether that's a common or rare thing.

SPACE.com: People assume evolution is directed, and it's always leading toward higher complexity and greater intelligence, but it's not.

Marcy: It's not. Dinosaurs show this in spades.

SPACE.com: You've said that we're about to enter a golden age of direct exoplanet imaging. Is that what the future holds — getting good, direct looks at alien planets to try to gauge their potential to support life?

Marcy: It is. There's two great things that we should be doing. One is that we should, as a species — and this means ESA [the European Space Agency], Japan, China, India, the United States, Canada — work together internationally to fund a space-borne telescope, probably interferometric, that can take pictures of Earth-size and Earth-like planets. We know how to do it.

Yes, it'll be expensive, but we do expensive things in science, and this is a great quest for humanity: Are there Earth-like and, indeed, habitable planets out there?

But the other thing to do — we should say it right away. We should have a full-fledged, Apollo-like SETI search. Why haven't we coherently gathered our resources and done SETI right?

SPACE.com: Finding alien intelligent life would be such a huge deal. It would change the way we think about ourselves and our place in the universe.

Marcy: Exactly. So why aren't we putting together our resources, nationally and internationally, and constructing a major radio telescope facility — and maybe, if there's money left over, an infrared facility — and sampling the universe for signals?

We know what to look for. That would be the rat-a-tat-tat of a radio signal. We don't know exactly what the code would be, but we'd be looking for pulses in the radio, in the infrared maybe, in the X-ray or UV. We'd have to think broadly. But this is a great quest for humanity.

It's the Armstrong, it's the Columbus of our time, essentially reaching out with radio waves and hunting foralien intelligent life. It would be a marvelous, inspirational effort. And right now we don't have enough going on, in my opinion.

Because it would mean — all 7 billion people on planet Earth would get up in the morning wondering, "Did they find the signal last night?"

SPACE.com: It makes you wonder why nations haven't joined together to do something like this. Economically, it would be a drop in the bucket.

Marcy: It's a drop in the bucket. Frankly, $1 billion would be good. It sounds like $1 billion is a lot of money. But not really. NASA's budget is $19 billion. Nineteen billion dollars every single year. So how about a billion of that for a SETI search? How about one year — 5 percent — to do SETI in a historic, Apollo-like way? I mean, Wow!

It puts Armstrong and the invention of fire sort of on a par. So it's worth one-nineteenth of one year's NASA budget. I think it's a great idea, and we know how to do it.

Yeah, it's a luxury. We need to feed the people on the planet Earth, we need to provide health care, we need to provide better education, we need to make sure that human beings are living. But we're doing that. And a billion is really a teeny fraction of many countries' annual budget.
 楼主| hkhtg090201 发表于 2011-2-3 03:17 | 显示全部楼层
本帖最后由 hkhtg090201 于 2011-2-3 12:13 编辑

Feb. 02, 2011 RELEASE : 11-030  
NASA 找到类地系外行星候选者!6个行星系统.
大约1千200个可能的行星和数以百计新的多行星系统.




  



NASA Finds Earth-Size Planet Candidates In Habitable Zone, Six Planet System   

WASHINGTON -- NASA's Kepler mission has discovered its first Earth-size planet candidates and its first candidates in the habitable zone, a region where liquid water could exist on a planet's surface. Five of the potential planets are near Earth-size and orbit in the habitable zone of smaller, cooler stars than our sun.

Candidates require follow-up observations to verify they are actual planets. Kepler also found six confirmed planets orbiting a sun-like star, Kepler-11. This is the largest group of transiting planets orbiting a single star yet discovered outside our solar system.

"In one generation we have gone from extraterrestrial planets being a mainstay of science fiction, to the present, where Kepler has helped turn science fiction into today's reality," said NASA Administrator Charles Bolden. "These discoveries underscore the importance of NASA's science missions, which consistently increase understanding of our place in the cosmos."

    The discoveries are part of several hundred new planet candidates identified in new Kepler mission science data, released on Tuesday, Feb. 1.

   The findings increase the number of planet candidates identified by Kepler to-date to 1,235. Of these, 68 are approximately Earth-size; 288 are super-Earth-size; 662 are Neptune-size; 165 are the size of Jupiter and 19 are larger than Jupiter.
   Of the 54 new planet candidates found in the habitable zone, five are near Earth-sized. The remaining 49 habitable zone candidates range from super-Earth size -- up to twice the size of Earth -- to larger than Jupiter.
   The findings are based on the results of observations conducted May 12 to Sept. 17, 2009, of more than 156,000 stars in Kepler's field of view, which covers approximately 1/400 of the sky.
     调查结果增加了由开普勒发现的行星的候选个数到1,235个。其中,68个近似地球大小,288个是超级地球大小;662..海王星大小;162..木星大小...19..比木星大。

     54个新行星候选者在可居住区发现,(其中)五个已接近地球大小。其余49个在可居住区的候选者范围从超级地球大小到达两倍的地球大小 一直到 比木星大。
    这一发现是基于开普勒的视野对2009年5月12日至9月17号,多达156,000恒星的天空观测结果,这一区域包括大约1/400天空。


"The fact that we've found so many planet candidates in such a tiny fraction of the sky suggests there are countless planets orbiting sun-like stars in our galaxy," said William Borucki of NASA's Ames Research Center in Moffett Field, Calif., the mission's science principal investigator. "We went from zero to 68 Earth-sized planet candidates and zero to 54 candidates in the habitable zone, some of which could have moons with liquid water."

Among the stars with planetary candidates, 170 show evidence of multiple planetary candidates. Kepler-11, located approximately 2,000 light years from Earth, is the most tightly packed planetary system yet discovered. All six of its confirmed planets have orbits smaller than Venus, and five of the six have orbits smaller than Mercury's. The only other star with more than one confirmed transiting planet is Kepler-9, which has three. The Kepler-11 findings will be published in the Feb. 3 issue of the journal Nature.

"Kepler-11 is a remarkable system whose architecture and dynamics provide clues about its formation," said Jack Lissauer, a planetary scientist and Kepler science team member at Ames. "These six planets are mixtures of rock and gases, possibly including water. The rocky material accounts for most of the planets' mass, while the gas takes up most of their volume. By measuring the sizes and masses of the five inner planets, we determined they are among the lowest mass confirmed planets beyond our solar system."

All of the planets orbiting Kepler-11 are larger than Earth, with the largest ones being comparable in size to Uranus and Neptune. The innermost planet, Kepler-11b, is ten times closer to its star than Earth is to the sun. Moving outward, the other planets are Kepler-11c, Kepler-11d, Kepler-11e, Kepler-11f, and the outermost planet, Kepler-11g, which is half as far from its star as Earth is from the sun.

The planets Kepler-11d, Kepler-11e and Kepler-11f have a significant amount of light gas, which indicates that they formed within a few million years of the system's formation.

"The historic milestones Kepler makes with each new discovery will determine the course of every exoplanet mission to follow," said Douglas Hudgins, Kepler program scientist at NASA Headquarters in Washington.

Kepler, a space telescope, looks for planet signatures by measuring tiny decreases in the brightness of stars caused by planets crossing in front of them. This is known as a transit.

Since transits of planets in the habitable zone of sun-like stars occur about once a year and require three transits for verification, it is expected to take three years to locate and verify Earth-size planets orbiting sun-like stars.

The Kepler science team uses ground-based telescopes and the Spitzer Space Telescope to review observations on planetary candidates and other objects of interest the spacecraft finds.

The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring through early fall. The data from these other observations help determine which candidates can be validated as planets.

For more information about the Kepler mission, visit:


http://www.nasa.gov/kepler

本帖子中包含更多资源

您需要 登录 才可以下载或查看,没有帐号?注册会员

x
 楼主| hkhtg090201 发表于 2011-2-3 03:23 | 显示全部楼层
Feb. 02, 2011 RELEASE : 11-030  
NASA 找到6个类地系外行星候选者!
NASA Finds Earth-Size Planet Can ...
hkhtg090201 发表于 2011-2-3 03:17



    这比去年的 黑洞 发现,砷基生命等,意义应该不在之下吧。
 楼主| hkhtg090201 发表于 2011-2-3 03:26 | 显示全部楼层
这比去年的 黑洞 发现,砷基生命等,意义应该不在之下吧。
hkhtg090201 发表于 2011-2-3 03:23



    NASA Finds Earth-Size Planet Candidates In Habitable Zone, Six Planet System   


  地球大小,可居住区域,这次的NASA用词很谨慎啊。
 楼主| hkhtg090201 发表于 2011-2-3 18:44 | 显示全部楼层
美宇航局宣布发现5个类地行星 可能存在液体水
2011年02月03日 14:28  中国新闻网 官方微博

  中新网2月3日电 美国宇航局2日宣布,美国开普勒太空望远镜在银河系发现了5个类地行星,且5个行星与其轨道中心恒星的距离都在液体水可能存在的距离范围内。液体水是生命存在的必要条件之一。

  宇航局同时宣布,开普勒望远镜还发现了一个类似太阳系的行星系。其中有5个和地球大小相似的行星。

  这一新发现的行星系被命名为“开普勒-11”。美国宇航局的行星研究专家杰克。里绍尔表示,这一发现不同寻常,在以往的发现中,地球以外的行星系很少有一个以上的轨道行星,“开普勒-11”是人类迄今为止在太阳系以外发现的、拥有3个以上轨道行星的行星系。

  宇航局称,所有围绕矮星运转的行星体积大于地球,其中最大的一个体积与天王星和海王星相近。

  五个行星中,最外缘的一个与其轨道中心矮星的距离大约是地球至太阳的一半。而中心矮星要比太阳小,温度也较低。

  里绍尔表示,这一行星系是目前发现的太阳系外最小的行星系,这些行星的表面有岩石和气体,也可能存在水。

  这一行星系距离地球约2000光年。外媒称,宇航局需要进一步的分析证实他们的确都是行星。
Everett 发表于 2011-2-4 11:50 | 显示全部楼层
回复 6# hkhtg090201


   
    NASA Finds Earth-Size Planet Candidates In Habitable Zone, Six Planet System   


距恒星一定距离都有一个Habitable Zone,只是说水在这个距离上是液态。另外kepler的任务就是找Earth-Size Planet
Everett 发表于 2011-2-4 11:51 | 显示全部楼层

【微波拟稿】kepler系外行星空间望远镜 距地2000光年 行星系统



腾讯科技讯(编译/Everett)据美国宇航局报道,开普勒空间望远镜在距地球2000光年处发现了一个极不同寻常的小太阳系,其由六颗行星和一颗黄色矮小的恒星组成,更令人惊奇的是,我们甚至不知道这样一个行星系统能够存在。
这个编号为kepler-11的行星系统由开普勒望远镜拍摄于去年八月份,解读后的数据显示该系统内各大行星的轨道十分靠近这颗恒星,且呈现出惊人紧凑、平整。换句话说,Kepler-11内部相当饱和,这已经超出了以往对大多数紧凑型行星系统的认识。
美国宇航局埃姆斯研究中心的科学家Jack Lissauer解释说:“这是个惊人的发现,这个行星系统是不同寻常的。一般观测时恒星只有一颗凌日行星(凌日是指行星圆面经过恒星表面,并在恒星表面投影下小黑点),而Kepler-11却出现了超过三颗(如图一)。
http://tech.qq.com/a/20110204/000043.htm

本帖子中包含更多资源

您需要 登录 才可以下载或查看,没有帐号?注册会员

x
Everett 发表于 2011-2-4 11:51 | 显示全部楼层
该系统中所有的行星都围绕着一颗黄色矮小的恒星,只比地球稍大。最大的一颗行星体积相当于天王星或者海王星。

最靠近恒星的,是一颗编号为Kepler-11b的行星,其到恒星的距离只有地球到太阳的十分之一(十分之一个天文单位)。往外依次排序是:Kepler-11c,Kepler-11d, Kepler-11e, Kepler-11f和Kepler-11g。

距该恒星最远的Kepler-11g,也只有半个天文单位(地球到太阳距离的一半)。也就是说,除了最外面的Kepler-11g外,其余五颗行星比太阳系中任何一颗行星都更靠近太阳。当然,即使是Kepler-11g也算相当靠近了。如果将他们全部放在我们的太阳系内【参见图二】,最外面的Kepler-11g的轨道介于金星和水星之间(一年只有118天)。而其他五颗的轨道则全部在水星和太阳之间(一年只有10-47天),且彼此相距很近。

本帖子中包含更多资源

您需要 登录 才可以下载或查看,没有帐号?注册会员

x
Everett 发表于 2011-2-4 11:51 | 显示全部楼层
通过对距离最近的五颗行星进行体积和质量的测量,我们可以确定其是目前发现最小的系外行星之一。这些行星由岩石和气体组成,可能含有水。行星质量中有相当一部分是岩石,而气体则占据了大部分行星体积。从结构和动力学上看,Kepler-11是一个典型的行星系统。Kepler-11d, Kepler-11e和Kepler-11f具有显著的气态结构,也就是说至少有三颗行星在该行星系统形成前几百万年就诞生了。

开普勒空间望远镜将继续对该系统进行观测,当观测到更多的行星凌日后,通过对恒星的光线以及引力的变化,将更精确地计算各个行星体积和质量。或许我们能发现第七颗行星,这对关于银河系内行星系统多样性的研究是很有帮助的。
 楼主| hkhtg090201 发表于 2011-2-4 12:12 | 显示全部楼层
回复  hkhtg090201


   
    NASA Finds Earth-Size Planet Candidates In Habitable Zone, Six Pla ...
Everett 发表于 2011-2-4 11:50



    谢谢!记得去年7月,一个比较知名的教授,根据Kepler的数据,得出发现140个类地行星的结论,遭到NASA批评,现在NASA好象尽量避免使用‘类地’这个词。
Everett 发表于 2011-2-4 13:23 | 显示全部楼层
回复 9# hkhtg090201


    至于把Earth-size理解成类地行星,是那些不懂这些术语具体意思的媒体,kepler的任务就是找Earth-size,而不是Earth-like。如果通俗点说,两者所表达的意思都差不多,说成类地行星更好理解,但是类地行星的要求较Earth-size更为严格,金星就是 Earth-size,而不是Earth-like。

那个教授叫:Dimitar Sasselov ,哈佛史密松森天体物理中心。他的确是说Earth-like,但人家所认为的Earth-like是Earth-size。我的理解是,就像一个人在某些领域有很深造诣,然后去给一群小学生做科普,这个用词自然也会小儿科一点。
takhiss 发表于 2011-2-16 22:32 | 显示全部楼层
那些行星上一定很熱
 楼主| hkhtg090201 发表于 2011-2-21 08:47 | 显示全部楼层
科学: 银河系可能有500亿个外星世界
2011年2月20日
   开普勒天文望远镜项目负责人William Borucki在美国科学促进会的会议上声称,银河系内有无数文明,可能多达5亿颗地外行星位于适宜居住的区域。
   到目前为止,开普勒望远镜发现了1,235颗候选行星,其中53颗行星位于适宜生命居住区域。而我们的银河系有3000亿颗恒星,很多有行星围绕。开普勒至今只研究了1/400的银河,它是利用行星凌日现象探测行星,因此需要很长的时间才能发现轨道离恒星较远的行星。Borucki估计银河系可能有超过500亿颗行星,其中5亿位于适宜生命居住的地区。
 楼主| hkhtg090201 发表于 2011-3-10 07:59 | 显示全部楼层
科学: 最类似地球的行星实际上不适宜生命
2011年3月09日

   上个月,NASA开普勒太空望远镜的行星搜寻团队,宣布发现了一颗最像地球的候选行星KOI 326.01,它的大小类似地球,运行轨道位于所在星系的适宜生命居住区域。这一发现令人兴奋不已,甚至一位天体物理学家还精确计算出了这颗行星的价值——223,099.93美元。
现在开普勒团队改变了他们的最初说法。峰回路转的起因是发现频道的一位事实调查员要求提供这颗行星的额外信息。研究人员翻出KOI 326.01附近图像后立刻发现不对劲。这颗行星的母星KIC 9880467与另一颗编号为KIC 9880470的恒星距离非常近,后者比前者更大更亮。研究人员意识到他们最初的计算有误,因为开普勒卫星将两颗恒星当成了一个光源。在重新计算后,研究人员称,KOI 326.01比以前预计的更大更炙热,它的母星更可能是KIC 9880470,它既不是类地行星也不位于适宜生命居住区域。
 楼主| hkhtg090201 发表于 2011-3-31 18:43 | 显示全部楼层
本帖最后由 hkhtg090201 于 2011-3-31 18:44 编辑

美国科学家搜寻外星人可能居住系外行星(图)
http://tech.sina.com.cn/d/2011-03-31/07315353033.shtml



外星人的家园?图中的黑点代表目前已发现的1235颗系外行星,背景则是它们各自绕转的中央恒星,按照大小比例进行排列。而作为对比,图中第一行右下方孤独的那个则是我们的太阳,如果仔细看,可以看到代表地球和木星的黑色小点。


PS:
shn117的作品向来有新异。

本帖子中包含更多资源

您需要 登录 才可以下载或查看,没有帐号?注册会员

x
 楼主| hkhtg090201 发表于 2011-4-2 17:41 | 显示全部楼层
kepler的副产品?:帮助揭示巨恒星的内部秘密。
http://spacefellowship.com/news/ ... the-first-time.html
 楼主| hkhtg090201 发表于 2011-5-27 20:05 | 显示全部楼层
开普勒多行星系统另人惊奇的牵引
http://spacefellowship.com/news/ ... planet-systems.html
 楼主| hkhtg090201 发表于 2011-5-29 14:14 | 显示全部楼层
本帖最后由 hkhtg090201 于 2011-5-29 14:14 编辑

上贴相关的中文:
三分之一的开普勒行星位于恒星系统内
http://www.astron.ac.cn/bencandy-3-5006-1.htm

您需要登录后才可以回帖 登录 | 注册会员

本版积分规则

QQ|申请友链|旗下论坛|小黑屋|手机版|航空航天港 ( 豫ICP备12024513号 )

GMT+8, 2017-7-25 06:43 , Processed in 1.330414 second(s), 20 queries , Gzip On.

Powered by Discuz! X3.2

© 2001-2013 Comsenz Inc.

快速回复 返回顶部 返回列表