Quizzes & Puzzles10 mins ago
The Largest Known Structure In The Universe
An international team of astronomers led by the University of Central Lancashire in the UK has discovered "the largest known structure in the universe." The team says that the recently observed large quasar group — comprised of dozens of highly energetic star-like objects — has a typical size of 500 Megaparsecs, but the size of the cluster is closer to 1200 Mpc at its widest point. To put that into perspective, the distance between our own Milky Way galaxy and Andromeda is about 0.75 Mpc.
The discovery has larger implications for the study of cosmology too. Albert Einstein’s Cosmological Principle states that the universe looks the same regardless of the observation point when viewed at a large enough scale. Einstein’s principle — combined with modern cosmological theories — suggests that astronomers shouldn’t be able to find structures larger than 370 Mpc. This particular large quasar group isn’t the only structure to question Einstein’s theory either: the team is also looking at "similar cases which add further weight to [the] challenge." The group of astronomers say that they will continue their research in the meantime.
Source: http://
No question, it's just pretty cool.
The discovery has larger implications for the study of cosmology too. Albert Einstein’s Cosmological Principle states that the universe looks the same regardless of the observation point when viewed at a large enough scale. Einstein’s principle — combined with modern cosmological theories — suggests that astronomers shouldn’t be able to find structures larger than 370 Mpc. This particular large quasar group isn’t the only structure to question Einstein’s theory either: the team is also looking at "similar cases which add further weight to [the] challenge." The group of astronomers say that they will continue their research in the meantime.
Source: http://
No question, it's just pretty cool.
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Ben Kersey is playing a little fast and loose with the cosmological principal when he says
//Albert Einstein’s Cosmological Principle states that the universe looks the same regardless of the observation point when viewed at a large enough scale.//
Wikipedia puts it well:
//The second implicit qualification is that "looks the same" does not mean physical structures necessarily, but the effects of physical laws in observable phenomena.//
http://
That is still good - similarities over large areas of the Universe are what first had Alan Guth proposing inflation and there may be implications for this.
I guess nearly 60 years after his death Einsteins name still has more appeal
Maybe we need to formulate Jake's law of scientific Journalism:
1 - Can we work Einstein in?
2 - If not can we work Stepehen Hawking in?
3 - If not use the term "Boffins"
//Albert Einstein’s Cosmological Principle states that the universe looks the same regardless of the observation point when viewed at a large enough scale.//
Wikipedia puts it well:
//The second implicit qualification is that "looks the same" does not mean physical structures necessarily, but the effects of physical laws in observable phenomena.//
http://
That is still good - similarities over large areas of the Universe are what first had Alan Guth proposing inflation and there may be implications for this.
I guess nearly 60 years after his death Einsteins name still has more appeal
Maybe we need to formulate Jake's law of scientific Journalism:
1 - Can we work Einstein in?
2 - If not can we work Stepehen Hawking in?
3 - If not use the term "Boffins"
-- answer removed --
Incidently the reason Astronomers use Parsecs and not light years is that it relates to how Astronomical distances are mesured.
The closest stars appear to move over the year as Earth goes around its orbit - this is called paralax and its the same effect you get as holding your finger out and opening and closing each eye in turn.
If a star seems to move by 1 second of arc (1/3600 of a degree) it's deemed 1 parsec (paralax second) away.
If you know the Earth Sun distance you can then work that out in miles and hence light years but any error in that gives you a corresponding error in your light years figure.
More distant objects can be worked out by their brightness or their periodicity or other factors abourt them but it is all based back on that parallax yardstick and as the distances get bigger so do the possible errors.
That is why Astronomers tend to use the parsec or megaparsec especially over very large distances
The closest stars appear to move over the year as Earth goes around its orbit - this is called paralax and its the same effect you get as holding your finger out and opening and closing each eye in turn.
If a star seems to move by 1 second of arc (1/3600 of a degree) it's deemed 1 parsec (paralax second) away.
If you know the Earth Sun distance you can then work that out in miles and hence light years but any error in that gives you a corresponding error in your light years figure.
More distant objects can be worked out by their brightness or their periodicity or other factors abourt them but it is all based back on that parallax yardstick and as the distances get bigger so do the possible errors.
That is why Astronomers tend to use the parsec or megaparsec especially over very large distances
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