s*****r
发帖数: 11545 | 1 虽然现在看见了，其实有可能在60亿年前就不存在了，这不是很可悲么？
http://news.yahoo.com/farthest-known-galaxy-universe-discovered
Farthest Known Galaxy in the Universe Discovered
A new celestial wonder has stolen the title of most distant object ever seen
in the universe, astronomers report.
The new record holder is the galaxy MACS0647-JD, which is about 13.3 billion
light-years away. The universe itself is only 13.7 billion years old, so
this galaxy's light has been traveling toward us for almost the whole
history of space and time.
Astronomers spotted the object using NASA's Hubble and Spitzer space
telescopes, with the aid of a naturally occurring cosmic zoom lens as well.
This lens is a huge cluster of galaxies whose collective gravity warps space
-time, producing what's called a gravitational lens. As the distant galaxy's
light traveled through this lens on its way to Earth, it was magnified.
"This cluster does what no manmade telescope can do," Marc Postman of the
Space Telescope Science Institute in Baltimore, Md., said in a statement
unveiling the discovery today (Nov. 15). "Without the magnification, it
would require a Herculean effort to observe this galaxy." Postman leads the
Cluster Lensing And Supernova Survey with Hubble (CLASH), which performed
the study.
The distant galaxy is just a tiny blob, and is much smaller than our own
Milky Way, researchers said. The object is very young, and it also dates
from an epoch when the universe itself was still a baby, just 420 million
years old, or 3 percent of its present age. [The Universe: Big Bang to Now
in 10 Easy Steps]
The mini galaxy is less than 600 light-years wide; for comparison, the Milky
Way is 150,000 light-years across. Astronomers think MACS0647-JD may
eventually combine with other small galaxies to create a larger whole.
"This object may be one of many building blocks of a galaxy," said the Space
Telescope Science Institute's Dan Coe, who led the study of this particular
galaxy. "Over the next 13 billion years, it may have dozens, hundreds, or
even thousands of merging events with other galaxies and galaxy fragments."
Astronomers are continually spotting ever farther galaxies as their
observation techniques and tools improve. The last object to hold the title
of farthest thing ever seen was the galaxy SXDF-NB1006-2, which lies 12.91
billion light-years from Earth. That object was sighted by the Subaru and
Keck Telescopes in Hawaii.
The CLASH survey, which discovered the new galaxy, MACS0647-JD, is working
on a cosmic census of 25 large galaxy clusters using Hubble's Wide Field
Camera 3 and Advanced Camera for Surveys. Those instruments first spotted
MACS0647-JD, and then the Spitzer telescope, which observes in infrared
light, confirmed the object was as far away as it appeared. | x*****8
发帖数: 10683 | 2 时间的尺度本身就和我们系统的运动速度有关，所以时间也是相对的。
我们不能说130亿年就接近宇宙的真实年龄了。
seen
billion
【在 s*****r 的大作中提到】
: 虽然现在看见了，其实有可能在60亿年前就不存在了，这不是很可悲么？
: http://news.yahoo.com/farthest-known-galaxy-universe-discovered
: Farthest Known Galaxy in the Universe Discovered
: A new celestial wonder has stolen the title of most distant object ever seen
: in the universe, astronomers report.
: The new record holder is the galaxy MACS0647-JD, which is about 13.3 billion
: light-years away. The universe itself is only 13.7 billion years old, so
: this galaxy's light has been traveling toward us for almost the whole
: history of space and time.
: Astronomers spotted the object using NASA's Hubble and Spitzer space
| s*****r
发帖数: 11545 | 3 文中说了宇宙年龄就140亿年左右。
【在 x*****8 的大作中提到】
: 时间的尺度本身就和我们系统的运动速度有关，所以时间也是相对的。
: 我们不能说130亿年就接近宇宙的真实年龄了。
:
: seen
: billion
| x*****8
发帖数: 10683 | 4 现在宇宙学家说的宇宙年龄是根据多普勒效应和大爆炸理论推算了，根本就忘记了相对
论效应，本虾不相信。
【在 s*****r 的大作中提到】
: 文中说了宇宙年龄就140亿年左右。
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