From the different types of singularities
found to the strange, explosive ways in which
they're formed, today we look at The Shocking
Truth About Black Holes.
Number 10.
Seeing A Black Hole
Black holes have caught the attention of scientists
studying the stars for centuries, but until
recently, they've never been able to catch
researchers' sight.
These enigmatic regions of spacetime live
up to their label as no light can escape the
blackness of their pull.
Because of this, it's not possible for the
human eye to directly detect its presence,
even with the assistance of X-rays, light,
or other electromagnetic radiation.
Instead, they are found by examining effects
commonly associated with a black hole's exceptional
gravitational pull.
So, witnessing events like a star stretching
towards a blank darkness, chances are it's
being torn apart by the grip of a black hole.
Number 9.
Our Own Backyard
The universe is massive, so it may seem like
black holes are the kind of rare anomaly to
be found millions of light-years away in other
galaxies.
One black hole, however, has been found at
the center of our very own Milky Way galaxy,
named Sagittarius A* for its proximity near
the constellation of the same name.
The discovery came from observing a series
of stars orbiting a focal point.
This black hole is a calculated 26 thousand
light-years away, and astronomers have figured
out the diameter of Sagittarius A* to be nearly
sixty million kilometers.
It's believed that black holes of this size
are at the center of most elliptical and spiral
galaxies.
As the great space vacuum steadily sucks in
the mass around it, you might be wondering...will
we earthlings get caught in the pull?
Well, worry not.
We may share the same galaxy as this supermassive
abyss, but we're still an extreme distance
from Sagittarius A*.
If anything, the presence of this black hole
in the Milky Way is beneficial in that it
grants Earth's scientists a closer look and
better understanding of their origin, nature,
and purpose.
Number 8.
Celestial Rebirth
It might surprise you to learn that different
types of black holes are believed to exist.
Supermassive ones like Sagittarius A* are
the size of millions of suns, but the next
step down in size comes in the form of Stellar
black holes.
These are formed when monstrous stars, around
20 times the size of our Sun or greater, burn
out of fuel.
Smaller stars don't elicit this type of reaction,
instead transforming into a white dwarf or
neutron star, which are incredibly dense but
compact stars that give off faint light in
comparison to the larger ones.
Gravity overtakes the naturally maintained
pressure of a large, terminal star, the kind
meant to hold its form intact, leading to
a collapse.
The resulting effect is a brutal fluster of
chaos as gravity flings the layers of the
star into space as the core crumples into
itself.
This is what is referred to as a supernova.
The imploding core forms into a singularity,
or a space of almost no volume and an endless
density.
Which just so happens to spell the ingredients
for a black hole.
Number 7.
Proximity Hazards
Studying black holes from Earth is a fascinating
endeavor, though as scientists progress, the
allure of a closer look increases.
But like storm chasers pursuing a tornado
or hurricane, this would be a greatly dangerous
pursuit in the name of scientific advancement.
Nearing the outer edge of a black hole brings
you closer to its gravitational attraction.
This is the black hole's event horizon, or
point of no return where no external force
can pluck you from its gravitational grasp.
This barrier isn't all bad, though, as the
existence of an event horizon dashes some
of the more common misconceptions with black
holes.
As scientists have learned that there's a
point to be crossed to enter the fateful tractor
beam of these great, dark phenomenons, they've
also concluded that these aren't just endless
vacuums slowly sucking up galaxies.
Particles must be in the black hole's vicinity
to be drawn in.
Therefore, the universe as we know it isn't
going anywhere soon...at least, not due to
a black hole.
Number 6.
The Ergosphere
Prior to reaching the event horizon, if approaching
a rotating black hole, you will find another
layer of gravitational pull called the ergosphere.
As the black hole spins, it pulls with it
the surrounding spacetime, like a twisted
cloth.
This surrounding region is oblong or pumpkin-shaped
depending on the form of the black hole, and
it acts as a type of whirlpool.
Whereas the event horizon is the point of
no return, the ergosphere can be escaped...if
an object is moving fast enough, that is.
The closer you get to the event horizon, the
more velocity required to break free from
this outer layer.
To make matters even more interesting, One
hypothesis from mathematician Roger Penrose
proposes that the energy from a black hole
can actually be removed by traveling through
the ergosphere!
Those particles that can force through a spinning
abyssal vortex are believed to actually gain
a 20.7% increase in energy.
The removal of this energy, in theory, would
lead to a slow in the spin of the black hole
and by association it would shrink the span
of the ergosphere, eventually becoming non-existent
should the singularity reach a stand still.
By the same token, though, the more intense
a black hole spins, the larger the ergosphere
becomes!
Number 5.
Size Range
In total, scientists have identified three
different types of black holes.
Two of these have already been mentioned in
this video: Stellar and Supermassive.
For a long time, astronomers believed these
were the only two types in existence.
But in the last two decades, researcher have
found enough evidence to conclude a third
type exists.
Fitting in between the relatively small sized
stellar black holes and gargantuan supermassive
black holes are intermediate-mass black holes.
These forms have a mass equivalent to hundreds
of suns, while a stellar black hole is less
than fifty suns and supermassives can have
a mass equal to tens of thousands of suns!
It's thought that these intermediate sizes
came to be by either the merging of stellar
black holes, the collision of massive stars
in dense clusters, or that they are simply
the remnant primordial black holes formed
from the Big Bang!
Another type of singularity has been hypothesized
in the form of miniature black holes, the
size of which would be smaller than our own
Sun.
Also thought to be a product of the Big Bang,
these would form from the rapid expansion
matter compressing slower-moving matter.
But this type of black hole has yet to be
discovered, and as such remains an unproven,
purely hypothetical phenomenon.
Number 4.
Rules of Time
Black holes alter spacetime and should you
ever have the privilege of witnessing something,
or someone, enter one, the time-related oddities
of the anomaly will be come quickly apparent.
According to Einstein's theory of general
relativity, time is affected by your own speed
when reaching extreme velocities near the
speed of light.
This speed is determined often by the intensity
of a gravitational pull, and it doesn't get
more intense than with a black hole.
From the perspective of an object surging
towards the center of a singularity, time
would continue moving forward at a constant
pace, with space and time conjoining into
one forward path.
But from a distance, it would appear as if
time is slowing down for the object, slowing
to a near stop at the event horizon, before
blinking out of existence entirely due to
an absence of light.
The singularity at that point becomes not
just a future destination, but literally the
future for the object, and attempting to slow,
stop or reverse course would be the same as
if you tried to slow, stop, or reverse the
flow of time.
Number 3.
X-Ray Astronomy
The first black hole found and widely accepted
is known as Cygnus X-1 for its location within
the constellation for which it shares its
namesake.
It was uncovered in the 1960s thanks to a
sub-orbital spaceflight and the use of X-ray
instruments which could detect cosmic X-rays
across the universe.
The data extracted from this analysis found
that a nearby blue supergiant star twenty
times the size of our Sun was bleeding into
a mysterious darkness, producing X-ray emissions
as a result.
This led to the determination that a black
hole was the source and the examination of
Cygnus X-1 intensified.
It took years to convince most astronomers
to get on board with this conclusion, though.
In 1974, brilliant physicist Stephen Hawking
made a wager with peer Kip Thorne that the
cosmic entity was not a black hole.
It took 16 years of studying and accumulating
evidence, but in 1990, Hawking finally conceded
defeat as the case for Cygnus X-1's existence
strengthened.
Number 2.
What About Wormholes
One of the popular topics in science fiction
works is the concept of wormholes.
These are hypothesized to be bridges across
the expanse of the universe, transporting
those who enter to regions lightyears away.
The name for these pathways originates from
the physicist John Wheeler after exploring
a similar theory conceptualized by Albert
Einstein and his assistant Nathan Rosen.
Wheeler compared the expanse of space to the
skin of an apple, stating an ant crawling
on the fruit has two choices to continue its
journey: either crawl around the surface,
or take a shortcut through a worm-built passage.
The idea is that our universe is wrapped around
a higher dimension, referred to as "the bulk",
and by having black holes open on opposite
sides of space, their infinite density would
cause them to merge within this "bulk".
Mathematically, this theory has some plausibility,
but the trip through such a wormhole is something
no living being could survive, as far as we
can tell.
That hasn't stopped them from being used in
pop culture, though, as wormholes have been
an essential part of works such as: Stargate,
Contact, A Wrinkle In Time, Interstellar,
Star Trek, Doctor Who, Sliders, and even the
Marvel Cinematic Universe.
Number 1.
First Photo
For years, scientists yearned for the chance
to see a black hole and in April of 2019,
that wish was finally granted.
By focusing on a pair of super-sized black
holes, one of which being Sagittarius A*,
the astronomers eventually found evidence
of the otherwise mysterious celestial formation.
Thanks to an array of telescopes spaced out
across the globe banning together to act in
unison as one large telescope, along with
some intense calculations and supercomputer
processing, the group of scientists were able
to capture something magical.
The gas and dust attracted to the black hole
heats up to billions of degrees due to the
immense pull of the center, creating a glowing
ring of hot matter encircling the three-dimensional
space.
