Posted on 05/16/2019 7:52:15 AM PDT by BenLurkin
There's a "dark impactor" blasting holes in our galaxy.
Stellar streams are lines of stars moving together across galaxies, often originating in smaller blobs of stars that collided with the galaxy in question.
Under normal conditions, the stream should be more or less a single line, stretched out by our galaxy's gravity, she said in her presentation. Astronomers would expect a single gap in the stream, at the point where the original globular cluster was before its stars drifted away in two directions. But Bonaca showed that GD-1 has a second gap. And that gap has a ragged edge — a region Bonaca called GD-1's "spur"... GD-1, it seems, was hit with that unseen bullet
This dense ball of unseen something plunging through our Milky Way offers physicists a new scrap of evidence that dark matter might be real. And it would suggest that dark matter is really "clumpy," as most theories about its behavior predict.
If dark matter is "clumpy," then it's concentrated in irregular chunks distributed roughly across galaxies — much like the luminous matter we see concentrated in stars and nebulae. Some alternative theories, including theories that suggest dark matter doesn't exist at all, ... and would have the effects of dark matter distributed smoothly across galaxies.
So far, Bonaca's discovery is one of a kind, so new that it hasn't yet been published in a peer-reviewed journal...
...she relied on data from the Gaia mission, an European Space Agency program to map billions of stars in our galaxy and their movements across the sky. It formed the best existing catalog of the stars that seem to be part of GD-1.
(Excerpt) Read more at livescience.com ...
Punched a Hole in the Milky Way. But What Exactly Is It?
The FIST of GOD!! : )
$7 You described “Q” from Star Trek.
He annoys everyone at once.
Good one!
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