Posted on 10/15/2016 2:43:17 PM PDT by LibWhacker
A new study from a team of international astronomers, led by astrophysicists from the University of Nottingham with support from the Royal Astronomical Society (RAS), has produced some astounding results: The universe contains at least two trillion galaxies, 10 times more than the highest previous estimates. What's more, the new study suggests that 90 percent of all galaxies are hidden from us, and only the remaining 10 percent can be seen at all, even with our most powerful telescopes. The paper detailing the study was published today in the Astrophysical Journal.
"We are missing the vast majority of galaxies because they are very faint and far away," said Nottingham Astrophysics Professor Christopher Conselice in an RAS press release. "The number of galaxies in the universe is a fundamental question in astronomy, and it boggles the mind that over 90 percent of the galaxies in the cosmos have yet to be studied. Who knows what interesting properties we will find when we study these galaxies with the next generation of telescopes?"
For two decades, astronomers have used the Hubble Space Telescope (HST) Deep Field images to try to estimate the number of galaxies in the observable universe. The previous estimate was 100 to 200 billion, and now we believe that huge number was too small by a factor of 10 or 20, depending on where your original estimate falls.
It is no easy task to count the galaxies in the entire universe. For one thing, as previously mentioned, we cannot see the vast majority of galaxies with our telescopes because they are too far or too faint or both. For another, the farther away we peer with the HST, the smaller the area of the sky we are observing is—Hubble Deep Field images cover about one millionth of the total area of the sky. This animation shows just how small an area a Deep Field image covers.
The results in the new study are the culmination of 15 years of work. An initial grant from the RAS allowed undergraduate student Aaron Wilkinson, now a phD student at Nottingham University, to perform initial galaxy-counting analysis work that laid the foundation for the larger study.
Professor Conselice, in partnerships with researchers at the University of Edinburgh and Leiden University in the Netherlands, used Wilkinson's work and data from telescopes around the world, particularly Hubble, to create 3D maps of different parts of the universe. Mathematical analysis of the models using the calculated density of the galaxies and the volume for each mapped region of space allowed the researchers to deduce how many galaxies we are missing in our observations, and in turn, how many there are in total spread across the universe.
In addition to pinning down a total number, the study analyzed the number of galaxies that were present in the distant past compared to the number of galaxies that exist now. By peering 13 billion light-years into the past, shortly after the Big Bang, the researchers found that there were 10 times more galaxies in the ancient universe than there are now (most of which were small, about the size of the satellite galaxies that orbit the Milky Way).
"This is very surprising as we know that, over the 13.7 billion years of cosmic evolution since the Big Bang, galaxies have been growing through star formation and mergers with other galaxies. Finding more galaxies in the past implies that significant evolution must have occurred to reduce their number through extensive merging of systems."
That "significant evolution" is the continuous merging of smaller galaxies into the larger ones we see today, and the new model could help researchers piece together the formation story of the modern universe with greater accuracy than ever before.
The sheer difference in the number of galaxies has far-reaching implications as well. Probabilistic equations that estimate the number of hypothetical alien civilizations, such as the Drake Equation, will need to be modified to account for the dramatic increase in the number of estimated galaxies out there—which makes it even more astronomically unlikely that we are alone among intelligent species.
In the face of such an expansive universe, it is easy to feel both awe and a sense of insignificance here on Earth. It is reminiscent of Carl Sagan's thoughts on the Pale Blue Dot image, a photo taken of Earth by Voyager 1 from a distance of 6 billion kilometers, almost as far as Pluto.
"It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known."
I had always thought the Universe might contain 2.5 to 3 times more Galaxies than we thought. But 10 to 20, that changes everything ..
20 trillion galaxies can’t be wrong ...
You cannot be more mistaken. Only a theological argument might suggest that. The evidence you are looking at is so infinitesimal as to be insignificant against the big picture.
Seems like a waste of time, energy and mass to me..........
IF there is indeed a God then I suspect we are not alone in His creation..........
But it supposedly couples to gravitation, and should then coalesce into dark matter galaxies, stars and planets, which would definitely seem to have an effect, crashing into each other, and presumably ordinary matter objects too. Yet, we don’t see any evidence of that.
I’m not a big fan of plugging something in just to make it fit the standard theory.
Almost makes you think there are millions of life planets (and moons) out there.
It’s a great big universe
And we’re all really puny
We’re just tiny little specks
About the size of Mickey Rooney.
It’s big and black and inky
And we are small and dinky
It’s a big universe and it’s ours
The Lord God is amazing.
I’m not a fan of the DM theory, either. I think it’s just a variable they stick into relevant equations to make them come out right. It’s not a physical entity, and they’ll never ‘discover’ any of it. In the meantime, we’ll just go with what works.
I guess we will soon have to move to a bigger universe!
Well, he did append “/s.”
If you think those galaxies are a long way away now - just wait.
OK, you waited. And just like I told you - they’re further away now then when you read that first sentence.
Trust me. I’ve got science on my side.
That could mean you believe:
A. There is intelligent life elsewhere in the universe.
B. With as many Dems as we have on Earth we don't qualify as "intelligent".
I'm betting on B.
I remember that joke when it was about the Sun.
Inflation, I guess. Certainly not education.
Wait a second, a year ago they were bragging they knew what happened the first trillionth of a second of its creation. I thought they knew Everything?
Yup, the same thought occurred to me. I think we have to keep in mind that the observable universe is not the same thing as the current universe. What we'll supposedly be able to see with the next generation telescopes, which are coming online soon, will be 10-20 times more galaxies than they previously thought were out there (in the observable universe). There are fewer in the current universe (none of which we can see; everything we see is in the past) because of all the mergers. At least, that's what I'm getting out of this article.
Have you seen the options as to who will run the most important and powerful country on our planet? Debatable.
20 x infinity? Wow.
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