V*******n
发帖数: 1 | 1 https://www.space.com/oldest-gamma-ray-burst-space-junk-mistake
A signal that scientists first believed was the ground-breaking discovery of
a gamma-ray burst from the oldest known galaxy in the universe was in fact
a reflection of sunlight from a spent rocket stage in Earth's orbit, a new
paper has found.
The disappointing conclusion comes from a team of Polish scientists
following a discussion involving several teams about the origin of the
serendipitous sighting made by one of the twin Keck telescopes in Hawaii in
2017. Whereas previous contributions to the debate focused on the
probability of seeing a satellite compared to an extremely rare gamma-ray
burst, the Polish team managed to track down the exact object that caused
the flash — a spent Breeze-M upper stage from a Russian Proton rocket.
The team behind the original observation, led by scientists from the
University of Beijing in China, set out to study one of the oldest galaxies
in the universe. Known as GN-z11, the galaxy is more than 13 billion light-
years away from Earth. That means telescopes can only see it as it looked
some 420 million years after the Big Bang, when the universe was very young.
The team used a near-infrared spectrograph called MOSFIRE mounted on one of
the Keck telescopes. Instead of capturing images, the spectrograph measures
the brightness of a celestial object at specific wavelengths of light. The
team was taking three-minute measurements of GN-z11 when suddenly, the
galaxy lit up. Within the next three minutes, however, the signal was back
to normal.
After ruling out other possibilities, the scientists concluded that the
sudden brightening must have been a gamma-ray burst, the brightest and most
energetic flash of light in the universe believed to be produced by
explosions of massive stars at the end of their lives, which astronomers
call supernovas. Lasting only a few seconds, gamma-ray bursts briefly
outshine everything else in the surrounding cosmos. But tracing their
origins has so far been elusive.
The team published their findings in the journal Nature Astronomy last
December. The discovery seemed like a big deal. Scientists have never
observed a gamma-ray burst in such an old galaxy, and seeing one would
reveal new information about the early universe. | l****e
发帖数: 25 | | V*******n
发帖数: 1 | 3 一回事，翻译不同，估计是个懂中文的ABC翻的。
【在 l****e 的大作中提到】
: 还以为是北京大学
: 。。。。。
| f******t
发帖数: 19544 | 4 难道不是。
【在 l****e 的大作中提到】
: 还以为是北京大学
: 。。。。。
| Y****1
发帖数: 1 | | r****d
发帖数: 1557 | 6 Linhua Jiang at Peking University in Beijing, China, and his colleagues were
using the Keck Observatory in Hawaii to study the faintest and oldest known
galaxy in the universe, GN-z11, when they saw the galaxy appear to grow
hundreds of times brighter for just under 3 minutes. | V*******n
发帖数: 1 | 7 等蚂蚁龙的卫星覆盖全天，每天都能发现新垃圾登Nature了。 | V*******n
发帖数: 1 | 8 江教授这回药丸，天牛不了了？
were
known
【在 r****d 的大作中提到】
: Linhua Jiang at Peking University in Beijing, China, and his colleagues were
: using the Keck Observatory in Hawaii to study the faintest and oldest known
: galaxy in the universe, GN-z11, when they saw the galaxy appear to grow
: hundreds of times brighter for just under 3 minutes.
| p*a
发帖数: 3350 | 9 江教授和靠研究米国假月壤起家的欧阳院士 谁更尴尬？
【在 V*******n 的大作中提到】
: 江教授这回药丸，天牛不了了？
:
: were
: known
| V*******n
发帖数: 1 | 10 https://www.space.com/oldest-gamma-ray-burst-space-junk-mistake
A signal that scientists first believed was the ground-breaking discovery of
a gamma-ray burst from the oldest known galaxy in the universe was in fact
a reflection of sunlight from a spent rocket stage in Earth's orbit, a new
paper has found.
The disappointing conclusion comes from a team of Polish scientists
following a discussion involving several teams about the origin of the
serendipitous sighting made by one of the twin Keck telescopes in Hawaii in
2017. Whereas previous contributions to the debate focused on the
probability of seeing a satellite compared to an extremely rare gamma-ray
burst, the Polish team managed to track down the exact object that caused
the flash — a spent Breeze-M upper stage from a Russian Proton rocket.
The team behind the original observation, led by scientists from the
University of Beijing in China, set out to study one of the oldest galaxies
in the universe. Known as GN-z11, the galaxy is more than 13 billion light-
years away from Earth. That means telescopes can only see it as it looked
some 420 million years after the Big Bang, when the universe was very young.
The team used a near-infrared spectrograph called MOSFIRE mounted on one of
the Keck telescopes. Instead of capturing images, the spectrograph measures
the brightness of a celestial object at specific wavelengths of light. The
team was taking three-minute measurements of GN-z11 when suddenly, the
galaxy lit up. Within the next three minutes, however, the signal was back
to normal.
After ruling out other possibilities, the scientists concluded that the
sudden brightening must have been a gamma-ray burst, the brightest and most
energetic flash of light in the universe believed to be produced by
explosions of massive stars at the end of their lives, which astronomers
call supernovas. Lasting only a few seconds, gamma-ray bursts briefly
outshine everything else in the surrounding cosmos. But tracing their
origins has so far been elusive.
The team published their findings in the journal Nature Astronomy last
December. The discovery seemed like a big deal. Scientists have never
observed a gamma-ray burst in such an old galaxy, and seeing one would
reveal new information about the early universe. | l****e
发帖数: 25 | | V*******n
发帖数: 1 | 12 一回事，翻译不同，估计是个懂中文的ABC翻的。
【在 l****e 的大作中提到】
: 还以为是北京大学
: 。。。。。
| f******t
发帖数: 19544 | 13 难道不是。
【在 l****e 的大作中提到】
: 还以为是北京大学
: 。。。。。
| Y****1
发帖数: 1 | | r****d
发帖数: 1557 | 15 Linhua Jiang at Peking University in Beijing, China, and his colleagues were
using the Keck Observatory in Hawaii to study the faintest and oldest known
galaxy in the universe, GN-z11, when they saw the galaxy appear to grow
hundreds of times brighter for just under 3 minutes. | V*******n
发帖数: 1 | 16 等蚂蚁龙的卫星覆盖全天，每天都能发现新垃圾登Nature了。 | V*******n
发帖数: 1 | 17 江教授这回药丸，天牛不了了？
were
known
【在 r****d 的大作中提到】
: Linhua Jiang at Peking University in Beijing, China, and his colleagues were
: using the Keck Observatory in Hawaii to study the faintest and oldest known
: galaxy in the universe, GN-z11, when they saw the galaxy appear to grow
: hundreds of times brighter for just under 3 minutes.
| p*a
发帖数: 3350 | 18 江教授和靠研究米国假月壤起家的欧阳院士 谁更尴尬？
【在 V*******n 的大作中提到】
: 江教授这回药丸，天牛不了了？
:
: were
: known
|
|
