Mysterious radio waves emitted from nearby galaxy
13:13 14 April 2010
by Stephen Battersby, Glasgow
Something in there is producing an unusually regular radio signal (Image: NASA/ESA/STScI/AURA)裡面有些東西正在生產一種不同尋常而有規律的無線電信號
There is something strange in the cosmic neighbourhood. An unknown object in the nearby galaxy M82 has started sending out radio waves, and the emission does not look like anything seen anywhere in the universe before.
有一些奇怪的東西在宇宙鄰居，一個不知道的物體在附近的M82星系，已開始發出無線電波，和發出的不看似之前在宇宙任何地方所見的任何東西。
"We don't know what it is," says co-discoverer Tom Muxlow of Jodrell Bank Centre for Astrophysics near Macclesfield, UK.
“我們不知道它是什麼，”英國麥克爾斯菲爾德附近的焦德雷爾班克天體物理學中心的共同發現者湯姆 Muxlow說。
The thing appeared in May last year, while Muxlow and his colleagues were monitoring an unrelated stellar explosion in M82 using the MERLIN network of radio telescopes in the UK. A bright spot of radio emission emerged over only a few days, quite rapidly in astronomical terms. Since then it has done very little except baffle astrophysicists.
那東西出現在去年5月，而Muxlow和他的同事們在監測一個在M82不相關的恆星爆炸，使用在英國的MERLIN射電望遠鏡網絡。一個無線電發射的光亮點出現幾天，很快地以天文述語來說。自此那它做了非常小，除困惑天體物理學家外。
It certainly does not fit the pattern of radio emissions from supernovae: they usually get brighter over a few weeks and then fade away over months, with the spectrum of the radiation changing all the while. The new source has hardly changed in brightness over the course of a year, and its spectrum is steady.
它當然不適合從超新星來的無線電放射模式：他們通常會在幾個星期後更光亮，然後在幾個月時間褪去，輻射的頻譜全時間不斷變化。新的來源的亮度在一年過程中幾乎沒有改變，和它的頻譜是穩定的。
變形速度
Warp speed
Yet it does seem to be moving – and fast: its apparent sideways velocity is four times the speed of light. Such apparent "superluminal" motion has been seen before in high-speed jets of material squirted out by some black holes. The stuff in these jets is moving towards us at a slight angle and travelling at a fair fraction of the speed of light, and the effects of relativity produce a kind of optical illusion that makes the motion appear superluminal.
然而它確看似是移動 -和快：它的表面橫向速度是4倍光速。這種表面的“超光速”移動，之前已見過，在高速射流物質被一些黑洞噴射時。這些噴出物中的東西，是移動邁向我們以一個微小的角度，和旅行以光速的一幾小部分，而相對論的效用產生一種視覺幻象，使移動出現超光速。
Could the object be a black hole? It is not quite in the middle of M82, where astronomers would expect to find the kind of supermassive central black hole that most other galaxies have. Which leaves the possibility that it could be a smaller-scale "microquasar".
A microquasar is formed after a very massive star explodes, leaving behind a black hole around 10 to 20 times the mass of the sun, which then starts feeding on gas from a surviving companion star. Microquasars do emit radio waves – but none seen in our galaxy is as bright as the new source in M82. Microquasars also produce plenty of X-rays, whereas no X-rays have been seen from the mystery object. "So that's not right either", Muxlow told New Scientist.
His best guess is still that the radio source is some kind of dense object accreting surrounding material, perhaps a large black hole or a black hole in an unusual environment. Perhaps the phenomenon also happens occasionally in our galaxy, but is more common in M82 because it is a "starburst" galaxy – a cosmic cauldron where massive stars are forming and exploding at a much higher rate than in the Milky Way, creating a lot of new black holes.
http://www.newscientist.com/article/dn18775-mysterious-radio-waves-emitted-from-nearby-galaxy.html?DCMP=OTC-rss&nsref=online-news
M82 Messier 82 Galaxy, Observatories, Chandra/Spitzer/Hubble
西元2007年08月04日
Here is what the signal looks like
這裡是信號所似的樣子
http://www.abovetopsecret.com/forum/thread561327/pg150年來 人類發給外星人的無線電信息
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