"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka' (I found it!) but 'That's funny...'" -- Isaac Asimov
~ ~ ~
"Dark Flow" of Billions of Stars Racing Away from Earth Towards Edge of Observable Universe (New JPL Discovery)
By Luke McKinney, via The Daily Galaxy
"Dark Flow" sounds like a new SciFi Channel series. It's not! Back in the Middle Ages, maps showed terrifying images of sea dragons at the boundaries of the known world. Today, scientists have observed strange new motion at the very limits of the known universe - kind of where you'd expect to find new things, but they still didn't expect this. A huge swath of galactic clusters seem to be heading to a cosmic hotspot and nobody knows why.
A new study has tracked the mysterious cosmic 'dark flow' to twice the distance originally reported in the Universe.The study was led by Alexander Kashlinsky at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
"This is not something we set out to find, but we cannot make it go away," Kashlinsky said. "Now we see that it persists to much greater distances - as far as 2.5 billion light-years away," he added.
The clusters appear to be moving along a line extending from our solar system toward Centaurus/Hydra, but the direction of this motion is less certain. Evidence indicates that the clusters are headed outward along this path, away from Earth, but the team cannot yet rule out the opposite flow.
"We detect motion along this axis, but right now our data cannot state as strongly as we'd like whether the clusters are coming or going," Kashlinsky said.
The unexplained motion has hundreds of millions of stars dashing towards a certain part of the sky at over eight hundred kilometers per second. Not much speed in cosmic terms, but the preferred direction certainly is: most cosmological models have things moving in all directions equally at the extreme edges of the universe. Something that could make things aim for a specific spot on such a massive scale hasn't been imagined before. The scientists are keeping to the proven astrophysical strategy of calling anything they don't understand "dark", terming the odd motion a "dark flow".
A black hole can't explain the observations - objects would accelerate into the hole, while the NASA scientists see constant motion over a vast expanse of a billion light-years. You have no idea how big that is. This is giant on a scale where it's not just that we can't see what's doing it; it's that the entire makeup of the universe as we understand it can't be right if this is happening.
Which is fantastic! Such discoveries force a whole new set of ideas onto the table which, even if they turn out to be wrong, are the greatest ways to advance science and our understanding of everything. One explanation that's already been offered is that our universe underwent a period of hyper-inflation early in its existence, and everything we think of as the vast and infinite universe is actually a small corner under the sofa of the real expanse of reality. Which would be an amazing, if humbling, discovery.