Galactic Bubbles: A ghostly story of intrigue and suspense.

Today we’re going to have a little fun with a recounting of a recent article I read in the New Scientist magazine.  It is a science magazine I enjoy as it is so transparent of the inconsistencies, failures, denials, and sometimes fraudulent data as well as good facts of science.  It keeps me engaged.

Each year my family, including my grown kids and their children, go on vacation together at Door County (Egg Harbor, WI). We have such a great time swimming, kayaking, star watching, hiking, and shopping.  The grandkids love to hear stories.  Their favorite stories are ghost stories and mysteries of that sort.  I love to make them up or retell tell the old ones.  I guess it is because I am a scientist.  Yes, an over-analytical, no-nonsense, hyper-logical, empirical experimental-chasing, geeky scientist. Don’t think we scientists have imaginations?  Well here is a ghost story that will be sure to scare you if not at least entertain you.

The universe is a difficult place to study.  There are material objects in it but if they are not close enough to see one must rely on the electromagnetic radiation (light and other radiation) they give off to determine the properties of those objects.  Our Milky Way galaxy has a dense core of stars where life on any planets that maybe there cannot be sustained due to dangerous radiation levels.  Other studies of the galaxy suggest that a massive black hole lies at the center of our galaxy and most other galaxies as well. Most peculiar is the current finding (it may change tomorrow) that the stars at the center of the galaxy are younger than our models of galactic evolution permit.  This is not easy to explain.  Neither dark matter nor dark energy help us to explain this strange discovery.

Our Galaxy the Milky Way.

Our Galaxy the Milky Way.

Now a galaxy is typically composed of 100 billion stars or so, sometimes more and sometimes less.  Our particular galaxy is a typical spiral galaxy, as best we can tell.  In 2008, images in the X-ray region of the electromagnetic spectrum were obtained from the direction of the galactic center.  It appears as two bursts of energy extend above and below the center of the galactic core. Nothing explains these enormous energetic bursts and here is where the story gets spooky.

In 2008 it was speculated that 100 good size stars fell into the black hole and being swallowed up, around 10,000 years ago, resulted in this post-catastrophic effect; the formation of X-ray bursts that now span some 25,000 light-years across and opposite the core of the galaxy.  These bursts were thought to be hour-glass shaped in 2008 and they just should not be there; so this too is really tough to explain.  Falling stars feeding a black hole help the story but there’s more to tell.   (Before this theory the X-ray energies were thought to be the result of typical galactic formation of black holes).

Most recently a new theory has emerged from details of a map made of the high energy regions using the Fermi Gamma-ray Space Telescope.  The hourglass bursts are actually bubble shaped.  The new details come with a new story.  This year Kelly Holley-Bockelmann from Vanderbilt University in Nashville, Tennessee, discussed the problem with Tamara Bogdanović from the Georgia Institute of Technology in Atlanta. They came up with a story of their own.  Let me warn you, it’s scary!

The Galactic Bubbles (also called a burp for short).

The Galactic Bubbles (also called a burp for short).

According to their hypothesis, a tiny galaxy having a central black hole may have plowed through the Milky Way billions of years ago.  As it spiraled down through to the center of our spiral galaxy it was stripped of its own stars until the black hole was left to hit the center of our galactic core.  And you know what this means when two black holes collide?  (Don’t you?).    Bubbles!  Big Bubbles!  Supergiant, galactic size, X-radiation bubbles!  This violent catastrophe must also have flung out the material for producing young stars in the middle of our ancient galaxy, disrupting gas clouds, squeezing them into stars as well.

Funny thing about this is that such collision and catastrophe should have kicked a lot of old stars right out of the ballpark… drifting aimlessly away from our galaxy.  We can’t find them.  Also, there should be “streak marks” of the little galaxy’s disruption of our galaxy.  We can’t find them either.  Is it possible that the collision occurred when the universe was only made of dark matter and black holes… thus leaving no sign that little galaxy was ever there!?

Now that’s a scary story!  Can’t wait to tell it to the grandkids.  One day, after the big bang, when everything was made from nothing,  dark matter made a black hole.  The hole was not empty but it was lonely and… well, you’ll just have to come to Door County to hear the rest.

Adapted from Giant Milky Way bubbles blown by black hole merger. March 7, 2013 by Nigel Henbest.



Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.