Artist's illustration of a bright gamma-ray burst. (Photo: NASA/Swift/Mary Pat Hrybyk-Keith and John Jones)
Astronomers discover humongous structure one-ninth the size of the observable universe
The mysterious structure's existence could contradict current models of the universe.
By: Bryan Nelson
August 6, 2015,
The sheer size of our universe is just about unfathomable, so you can imagine the surprise that researchers must have experienced when they recently discovered a structure within our universe that measured 5 billion light years across. That's more than one-ninth the size of the entire observable universe, and by far the largest structure ever discovered.In fact, this mysterious structure is so colossal that it could shatter our current understanding of the cosmos."If we are right, this structure contradicts the current models of the universe," said Lajos Balazs, lead author on the paper, in a press release by the Royal Astronomical Society. "It was a huge surprise to find something this big – and we still don't quite understand how it came to exist at all."Just what is this massive structure? It's not a single, physical object, but rather a cluster of nine massive galaxies bound together gravitationally, much like how our Milky Way is part of a cluster of galaxies. It was discovered after researchers identified a ring of nine gamma ray bursts (GRBs) that appeared to be at very similar distances from us, each around 7 billion light years away.GRBs are the brightest electromagnetic events known to occur in the universe, caused by a supernova. Their detection typically indicates the presence of a galaxy, so all of the GRBs in this ring are believed to each come from a different galaxy. But their close proximity to one another suggests that these galaxies must be linked together. There is only a 1 in 20,000 probability of the GRBs being in this distribution by chance.A mega-cluster of this size shouldn't be possible, at least not if you think in terms of our current theories. Those theories predict that the universe ought to be relatively uniform on the largest scales, meaning that the sizes of structures shouldn't vary by much. In fact, the theoretical limit to structure size has been calculated at around 1.2 billion light years across.If the Hungarian-American team's calculations are correct, then this giant new structure-- which measures in at over 5 billion light years across — would blow that classic model out of the water. In fact, either the researchers' calculations are wrong on this, or scientists will need to radically revise their theories on the evolution of the cosmos.Needless to say, this GRB cluster discovery has the potential to cause a sweeping paradigm shift in astronomy. At the very least, it reminds us just how small our view of the universe really is.Read more:
http://www.mnn.com/earth-matters/space/stories/astronomers-discover-humongous-structure-one-ninth-size-observable-universe#ixzz3i3Bw6oQg
The "observable" universe is a very small portion of the entire universe.
ReplyDeleteAccording to Alan Guth ( Alan H. Guth
The inflationary universe: the quest for a new theory of cosmic origins. Basic Books. pp. 186–. )
the total universe is 3 X 10^23 times larger than the tiny part of the universe that is observable by us.
"Observable" means we can detect light from emanating from sources within a sphere (with us--the observor-- at its center)with a diameter of 93 billion light years.
According to Wikipedia the diameter of the observable universe is 28 gigaparsecs
(93 billion light years,8.8 X10^26 meters,or 5.5 X 10^23 miles) putting the edge/boundary of the "observable" universe at 46.5 billion light years from us.
So 5 billion light years is about 1/18 (not 1/9) of the diameter of the observable universe.
Still humungous though!
My calculation yielded a different number.
ReplyDeletePlease explain the mistake.
(1 light year = 9.46 X 10^12 km=
9,461,000,000,000 km or 5,878,000,000,000 miles)
Knowing the age of the universe to be
13.7 billion years (13,700,000,000, years is 1.37 × 10^10 years)
In 1 year light travels 9.46 X10^12 km
In 13.7 billion years light travels
9.46 X 10^12 km X 1.37 × 10^10 years=
1.29602 × 10^23 kilometers
This is as far as light could travel in 13.7 billion years.
So this is the radius of the universe!
So the diameter of the universe is
2X( 1.29602 × 10^23 kilometers)=
2.58 × 10^23 kilometers
So diameter of universe in light years is:
2.58 × 10^23km ÷ 9.46 X10^12 km
=.27 X 10^11
=2.7X 10^10
=27,000,000,000
27 billion light years
More about this giant cluster:
ReplyDeletehttp://news.discovery.com/space/astronomy/giant-mystery-ring-of-galaxies-should-not-exist-150804.htm#mkcpgn=rssnws1
ReplyDelete"Laniakea: Our home supercluster"
http://www.youtube.com/watch?v=rENyyRwxpHo&feature=youtube_gdata_player
For all its vastness, the Milky Way is just one of billions of galaxies in the universe. Recently, scientists mapped the 100,000 or so galaxies near the Milky Way and found that it's part of a broader supercluster called Laniakea.
This supercluster is made up of several forks, with the Milky Way lying on one distant fringe of it.
What's more, it borders another supercluster (called Perseus-Pisces) that's moving in the opposite direction, and both seem to fall in a broader web, made up of dense supercluster networks alternating with relatively empty voids.