astronomers struggle with one of the biggest mysteries of our nearby universe
a discovery made over a decade ago that only now may be unraveling two bubbles of powerful
and deadly gamma rays light years across emanating from the core of our galaxy welcome to Factnomenal
in today's video we dive deep into the fascinating mystery of the strange phenomenon astronomers call
fermi bubbles they are nothing less than a completely new type of cosmic object we
have never seen before they are deadly and we're not sure how they came to be
the fermi gamma-ray space telescope named for architect of the nuclear age enrico fermi
launched in 2008 to explore the most energetic form of radiation out there
this gave astronomers a fantastic tool to study everything from jets of gas ejected
from around black holes to the birth and early years of the universe two years after launch
astronomers using fermi announced the startling discovery two giant gamma radiation bubbles extend
above and below the plane of the milky way in both directions the bubbles are expanding at 2.2
million miles per hour or 3.5 million kilometers per hour on each side of our galactic center
where they touch to form a shape reminiscent of two soccer balls balanced atop one another
and they span more than half of the visible sky as doug finkbiner the harvard smithsonian
center for astrophysics astronomer who discovered the phenomenon says
they are something wholly new and quite exciting what we see are two gamma-ray emitting bubbles
that extend 25 000 light years north and south of their galactic center finkbiner said before
noting their mystery we don't fully understand their nature or origin the bubbles eluded earlier
detection by astronomers studying gamma rays due to diffuse emission the reaction of other
gamma rays moving at nearly light speed when they interact with light and gases in the milky way
fermi researchers had to wade through this morass to make their startling discovery
gamma rays are to put it mildly radical members of the electromagnetic spectrum billions of times
more energetic than visible light they do not regularly reflect off objects the way light does
but instead penetrate them in a destructive manner gamma radiation through the human body
for example can immediately damage chromosomes and cause ionizations that wreak havoc on tissue
stopping the potentially deadly rays requires several inches of dense shielding such as
lead or even several feet of concrete there is good news however as few gamma rays reach us on
earth's surface while our sun has a tremendous amount of the rays internally they reach its
surface as much less dangerous forms of light without the toxic mixture of x-rays and gamma
rays the sun does not emit them and other stars don't either gamma radiation that happens to be
flying around interstellar space is from very violent and energetic events such as supernovae
astronomers say the likelihood of a nearby gamma-ray burst striking earth is low
supermassive stars in our region of space are rare and even binary systems that could potentially
spark a dangerous event are not close if we were subjected to such an outburst the result will be
anything from destroying a significant part of our protective atmosphere to a mass extinction event
so exactly what cataclysmic and mysterious event created these enormous fermi bubbles
the center of the milky way is a crazy maze of invisible and interconnected swoops of energy
dominated by the mickey mouse ears of the fermi bubbles from end to end the two
bubbles span almost 50 000 light years close to half of the diameter of the entire galaxy
the enormous amount of energy it took to unleash two super giant balls of gamma rays
is puzzling to astronomers but there are clues the configuration of the fermi bubbles above
and below the milky way center point to a suspect our supermassive black hole we call sagittarius a
at a mere 26 000 light years from earth sagittarius a is in a prime position for study
and nasa's chandra x-ray observatory among others is busy doing exactly that the black hole in the
center of our home has about 4 million times the mass of our sun and gas swirls around it that is
heated to as much as 18 million degrees fahrenheit or 10 million degrees celsius researchers using
chandra concluded that less than one percent of material initially with sagittarius a's
gravitational influence actually takes the plunge past the event horizon the point of no return
much of it is ejected raising the possibility of a violent event or series of events that
caused our deadly twin bubbles of gamma rays which brings us back to the original question one in the
universe sent these super fast bubbles of deadly radiation hurling out of the center of our galaxy
supermassive black holes sometimes splash gigantic jets of ionized matter from galactic centers at
near light speed this has been observed by astronomers who do not know why this happens
researchers using several computer simulations determined that both the bubbles and nearby x-ray
structures may have been borne by a massive shock wave propelling these jets in opposite directions
the process the research team concluded would have lasted as much as a million years starting with
an almost unimaginably powerful blast the shock waves would have to plow through hot gas on both
sides of the galactic core as they heated and compressed to break out the hourglass structure
formed and the shock waves roared into space in both directions resulting in the fermi bubbles
david spurgle an astrophysicist at princeton university says the phenomenon has been seen
in other galaxies whatever the energy source behind the huge bubbles may be it is connected
to many deep questions in astrophysics there are theories that an unfortunate star drifted too
close to sagittarius a and was torn apart the violent event released enormous levels
of gravitational energy in an instant which led to the bubbles that have spread ever since
some theories suggest that our supermassive black hole has nothing to do with the birth of the fermi
bubbles that it is simply coincidental in the neighborhood of their beginning
that perhaps dozens or hundreds of densely packed stars near the galactic core when supernova
and discharge the gargantuan plumes of radiation and energy that form the bubbles
in 2020 researchers using the e-rosita x-ray satellite made a perhaps still more exciting
discovery they've found two even larger bubbles extending above and below the milky way center
and they are being pushed outward by the fermi shock waves discovered a decade earlier
bubbles within bubbles and the new e rositas are over 70 000 light years from end to end what
this groundbreaking discovery has accomplished according to dr mathias ruskowski an astronomer
at the university of michigan he's overruling the previous theory of a giant starburst as the
origin of the bubbles we not only can rule out the starburst model but we can also fine-tune
the parameters that are needed to produce the same images within that supermassive black hole
model meaning researchers may now construct more accurate simulations of the energy release that
set the enormously powerful bubbles in motion accounting for hydrodynamics gravity and cosmic
rays the previous starburst origin story is kaput according to dr ellen zweibel also of
the university of michigan because of the time that such an event would last she explains that
the length of time into which a starburst would inject the energy that forms the bubbles is
about 10 million years both the fermi and erosita bubble she says would appear completely different
than they do the end result at least thus far is that researchers believe that the black hole
model which theorizes an enormous explosion from sagittarius a accurately predicts the sizes of
both sets of intergalactic bubbles this model also gives clues as to how supermassive black holes
believed to be at the center of virtually every large galaxy interact with their hosts astronomers
want to know why these black holes such as our sagittarius a grow in a controlled manner in their
host galaxies instead of wildly out of control further studies of these mysterious bubbles may
go far in revealing this relationship but while we may be closer to an answer concerning the origin
of the fermi and erosita bubbles what's happening inside them keeps getting more and more strange
researchers using the ice cube neutrino observatory a fascinating facility in
antarctica near the south pole perched on a glacier recently discovered 10 sources of
high-energy neutrinos inside the fermi bubbles translation some strange subatomic interactions
are going on in the bubbles and astrophysicists can only speculate as to what they are
so what do you think about these immense bubbles of potentially deadly radiation racing out from
our milky way how much stranger is our universe getting every time we make a new discovery
tell us in the comments and as always thank you for watching Factnomenal