美国航空航天局(NASA) 将在五月十五日召开大型记者电话会议，宣布迄今为止发现的有关暗物质存在的最有力的证据——在0024——17团内存在的一个诡异的暗物质圈。这个圈是该团内首次观测到的与星系和热气不相符合的结构。这个发现将在六月二十日的新一期《天体物理》杂志上发表。

这中文可能不太符合科学术语.先看意思吧. 据说暗物质和正常星系或天体物质相遇时,不会发生碰撞,而是穿透而过. 就像电影里鬼穿过人体一样. 谁知道更多的来扒一扒好吗?

小6 涅？？？看来只有她还能八一把！

都说是暗物质了。看不见、摸不着、仪器、仪表、天文望远镜以及各种各样的“波”都探测不着的。所谓”观测到“是嘛意思？观测得到的就不叫什么“暗物质”了。人家刘星都说了，”我用数学看得到”。

记得好像是某次两颗星星相撞发出的光透露出了周围暗物质的隐约结构。刘星说了暗物质是宇宙的基础基质，应该不像是一楼说的某团东西。

换句话说，NASA 15日要讨论的仍然是一种对暗物质存在的判断,它要提出的新证据,是用哈勃望远镜观测到的,0024——17星团内不符合常规的状况.它所说的暗物质"圈",大概是暗物质可能的存在的一个区间范围吧.

晕~~~~本来还想跟明心解释一下我们为什么对暗物质这个话题感兴趣，现在看来，天堂口果然爱好广泛，而且懂的颇多哦！我一直把暗物质和以前曾经认为的黑洞联系起来的。

15日就要到了,可以注意一下NASA爆料内容.

现在看来，天堂口果然爱好广泛，而且懂的颇多哦！----------------其实我也是因为刘烨演了这部电影才去了解暗物质的，懂的这一点咚咚已经全吐出来了。

就像电影里鬼穿过人体一样＝＝＝＝那么说，“鬼”完全符合暗物质的定义喽？！

看来“鬼”是客观存在的。。。。我是不是可以得出这样的结论？嘿嘿。

“鬼”完全符合暗物质的定义。。。。看来“鬼”是客观存在的。。。。======呵呵，我今天早上也在琢磨这两者的相同性呢，不光是鬼与人,暗物质与物质二者相遇不会发生碰撞，而且“鬼”和暗物质似乎都是人类在无法用现有科学理论解释自然现象时提出的另类解释方法。数学课里老师常常要求我们不要“guess"(猜测)答案, 却又经常要我们“estimate"(估计),于是就有学生发明了“guestimate" 这个合成词.看来,就像鬼是俗人的guestimate一样,暗物质是专业人士的guestimate.这样说对刘星们太不尊重了哈,我也学某冰面壁思过去了.88

啊？现在才看到这个帖子这东西我也扒不了啊 = = 惭愧

大致来说,目前暗物质的发现不是因为人们观察到了它,而是因为人们没有观察到按正常理论推算应该观察到的结果,比如,两颗星星相撞后,根据计算应该发生的情况同观察到的情况相去甚远,人们才猜测有暗物质的存在. --------------天堂口姐姐说的对，一般来说类似暗物质存在的证据都是靠与先有理论推测结果不一致及其具体的差别来取得的。依靠正常的探测手段是不可能直接探测到的。

Hubble finds ring of dark matterBALTIMORE, May 15 (UPI) -- The Hubble Space Telescope has found a "ghostly" ring of dark matter that formed long ago during a titanic collision between two galaxy clusters.The discovery is said to be among the strongest evidence yet that dark matter exists.Although astronomers do not know what composes dark matter, they hypothesize it is a type of elementary particle that pervades the universe."This is the first time we have detected dark matter as having a unique structure that is different from both the gas and the galaxies in the cluster," said astronomer M. James Jee of Johns Hopkins University. Jee is a member of the team that spotted the dark matter ring.The ring, measuring 2.6 million light-years across, was found in the cluster CL0024+17, 5 billion light-years from Earth.Said Jee: "I was annoyed when I saw the ring because I thought it was an artifact, which would have implied a flaw in our data reduction. I couldn't believe my result. It took more than a year to convince myself that the ring was real."A paper on the discovery is to be published in the June 1 issue of the Astrophysical Journal.Copyright 2007 by United Press International. All Rights Reserved.

"This is the first time we have detected dark matter as having a unique structure that is different from both the gas and the galaxies in the cluster,"=================================NASA的说法好像很自信.

呵呵一才就是抽的看帖回帖是美德带着诱惑的少爷的来了

A big find in the hunt for elusive dark matterAstronomers cite new evidence that the unseen 'glue' holding galaxies together really exists.By Peter N. Spotts | Staff writer of The Christian Science Monitor Building cosmic maps of matter no one can see may seem like a strange way to make a living. But for astronomer Myungkook James Jee, the work may have netted evidence that seals the case for the existence of dark matter – unseen, "missing mass" first invoked in 1933 to explain why spinning galaxies and galaxy clusters don't tear themselves apart as they twirl.Dr. Jee and his colleagues announced Tuesday that they have discovered a wispy ring of dark matter around a huge cluster of galaxies 5 billion light-years from Earth. The researchers didn't spot the dark matter directly; it doesn't emit light. Instead, they analyzed the way its gravity bends light from galaxies behind it – an effect called gravitational lensing. If confirmed, the result would rule out other, more exotic notions that have emerged to explain how galaxies and galaxy clusters are held together.Typically, dark matter's gravity is thought to act as a scaffold for building galaxies and structures that astronomers can detect. That was their only initial explanation for how these structures held up – otherwise the mass in luminous matter wouldn't yield enough gravity to hold galaxies or galaxy clusters together as they rotate. So, astronomers surmised, bright and dark matter generally should go hand in glove.Some scientists, however, are uncomfortable relying on the unseeable to act as this cosmic glue. For nearly 25 years, they have sought other ways to explain the structures they see. For example, some suggest that you don't need to invoke dark matter if gravity behaves differently at huge spatial scales than it does at small scales. Such alternative explanations couldn't be ruled out – unless someone could find dark matter out there on its own, with a structure unlike that of the nearest clusters.Jee's discovery gets closer than ever to doing just that. It suggests that the ring of dark matter, 2.6 million light-years wide, is clearly separated from the hot gas and other luminous matter in the cluster. If the result holds up, this stand-alone dark matter would close the door to these other theories, some astronomers say.It would also sustain a long-cherished assumption underlying space science: Gravity works the same way everywhere in the universe as it does on Earth. The results "are suggestive," acknowledges Douglas Clowe, an Ohio University astronomer who is not part of Jee's team. They don't help identify the exotic subatomic particles dark matter is made of. But if confirmed, the results would "remove the last conspiracy theories against dark matter."Jee, an astronomer at The Johns Hopkins University in Baltimore, notes that at first he didn't believe his results. His team was mapping the distribution of dark matter in the galaxy cluster, dubbed CL0024+17, using the Hubble Space Telescope's Advanced Camera for Surveys. When the team saw the ring in the data, members suspected it came from flaws in a computer program they'd used. "We spent nearly a year searching for the cause of the problem," Jee says. The more the group tried to remove the ring, the more distinctly it showed up.Then the group came across an earlier study of the cluster indicating that 1 billion to 2 billion years ago the collection of galaxies collided with another galaxy cluster. The team realized it was viewing the remnants of the collision end-on. The dark-matter ring was, in effect, a ripple expanding out from the collision.Last year, Dr. Clowe and colleagues reported the first direct evidence for dark matter in another cluster that had endured a collision. But in terms of testing alternative ideas on missing mass, it provided only half a loaf, he explains. The collision had stripped the cluster of its hot gas, so the dark matter was decoupled from that batch of luminous matter – which accounts for most of a cluster's luminous mass. But the dark matter still appeared to be associated with the galaxies in the cluster. Jee's team apparently has found dark matter that has been fully pushed out of the nest.The findings are controversial, notes Cal Tech astronomer Richard Massey, who this year published a map of dark matter embracing some 500,000 galaxies. The latest measurements come from only one instrument; other studies combine optical images with data taken at other wavelengths. Moreover, "the signal is very weak. Some people are not yet convinced it's more than an artifact," he notes.Follow-up studies may have to await the launch of the James Webb Space Telescope, slated for 2013. The Hubble camera Jee's team used blew a fuse and ceased operation in January, and it's not clear whether a space shuttle mission can repair it.

科学家发现暗物质存在最有力证据2007-05-16 19:26　　 【查看评论】　【字号：大 中 小】　【收藏此页】　【关闭窗口】　　长江网讯　据新浪科技讯 据国外媒体5月16日报道，美国科学家当地时间15日表示，数十亿年前宇宙碰撞所产生的暗物质朦胧光环提供了迄今为止有关这种神秘物质存在于宇宙中的最有力证据。　　通过美国宇航局哈勃天文望远镜所拍摄的照片，天文学家发现了这条暗物质光环，光环是由距地球50亿光年远的两个星系团碰撞形成的。美国巴尔迪摩约翰斯·霍普金斯大学天文学家姆宇库·詹姆斯·吉(Myungkook James Jee)在接受记者采访时兴奋地说：“这是暗物质存在的最有力证据。”暗物质是相对于构成恒星、行星等星体的普通物质而言，天文学家认为，宇宙中85%的物质都是暗物质，但有关暗物质存在的证据却一向难以获得。　　暗物质是人的肉眼所无法直接看到的，它既不发光，也不反射光。但天文学家通过观察暗物质重力使更遥远星系发出的光产生弯曲，从而推测暗物质存在于星系团中。不过他们确实不清楚暗物质的构成，只是认为它可能是某种粒子。加州理工学院天文学家理查德·梅赛(Richard Massey)说，最新研究发现将会在天文学界面临严重质疑。梅赛本人并未参加此次研究。他说：“这项研究要是得到佐证，确实令人激动万分。但若想让人相信这条光环，天文学家还想要看到可以验证这种结论的一些独立观测结果。”　　哈勃望远镜以前的观测数据显示了两个星系团的另一次碰撞，暗物质在碰撞中的活动看上去与此次有所不同。美国科学家是在研究一个代号为Cl 0024+17的星系团中暗物质分布时，偶然间发现暗物质存在新证据的。由于对这条光环的起源充满好奇，他们对以前的一项研究进行了分析，这项研究显示一个星系团在10亿年至20亿年前与另一个星系团相撞。　　科学家设计出模仿这种碰撞的电脑模型，表明两个星系团相撞时，暗物质如瀑布般向新形成的星系团中心方面喷涌而去，接着，在重力的拉力下速度放缓，开始向外侧流动。吉说：“两个星系团的碰撞产生了大量暗物质，在背景星系团的外形上留下了独特的足迹。这种景象就好比将鹅卵石投向池塘，表面产生涟漪一样。随着水波经过它们上面，鹅卵石的外形似乎在不断变化。同样，光环的背景星系显示，由于这条密集光环的存在，它们的外形变化很连贯。”　　尽管科学家此前也曾在其它星系团发现过暗物质，但从未观测到暗物质与热气及构成这些星系团的星系分离是如此的独特。梅赛说：“鉴于暗物质是宇宙最常见的物质，我们眼下对其知之甚少，这一情况确实令我们感到十分困窘。”(杨孝文)