Kind: captions
Language: en
this is the first ever image of a black
hole
released by the event horizon telescope
collaboration on april 10th 2019. it
shows plasma orbiting the supermassive
black hole at the center of the galaxy
m87
the bright region shows where plasma is
coming towards us and since it's
traveling near the speed of light it
appears brighter when coming towards us
and dimmer when going away
this is called relativistic beaming from
the images scientists can tell that the
plasma is orbiting clockwise it takes
around two days for the plasma to
complete one orbit
here we are looking at the black hole
using electromagnetic waves with a
wavelength of 1.3 millimeters radio
waves this was the part of the spectrum
used to make the image because it can
show us the features close in to the
event horizon and it can pass through
the accretion disk and interstellar dust
to reach our telescopes
the supermassive black hole in m87 is
very active meaning it's constantly
feeding on lots of matter from its
glowing hot accretion disk but it also
has narrow collimated jets above and
below it here shown in blue thought to
be created by incredibly strong magnetic
fields
the jets extend out at least 5 000 light
years and one of them appears to be
pointing almost straight at us
relativistic beaming is again the reason
we can see the jet coming towards us in
this hubble space telescope image but
not the one going away
since the jet is pointed almost straight
at us i'm thinking our perspective is
almost perpendicular to the accretion
disk
but let's have a look at what we would
see if we were looking at different
orientations
the warping of space-time around the
black hole means we can see light even
from parts of the accretion disk behind
the black hole
they are lensed above and below the
shadow region
not gonna lie this is so trippy i could
stare at it for a long
time so the big question most people are
going to be asking is
why is the image so fuzzy
the answer is because it's so tiny
don't get me wrong the black hole itself
is huge super massive in fact as
measured from this picture the black
hole has a mass 6.5 billion times that
of our sun
the actual size of its shadow is nearly
the size of our solar system
but located 53.5 million light years
away its size from our perspective is
only about 40 micro arc seconds that's
the angle it makes on the sky
to understand what that means take the
whole sky and divide it into 180 degrees
then divide a degree into 60 arc minutes
and an arc minute into 60 arc seconds
divide an arc second into a hundred
and into a hundred again
and into a hundred once more
and that
is the size of the black hole shadow
only about 40 micro arc seconds it puts
us at the very limit of what we are
technologically capable of seeing
in fact to get this sort of resolution
due to the basic law of physics the
diffraction limit we needed a telescope
the size of the earth
that being impractical the scientists
used eight telescopes spread across the
globe
they all simultaneously observed m87 and
as the earth rotated that helped fill in
the earth-sized telescope that they were
trying to simulate
but m87 was not the only black hole they
looked at they also observed the
supermassive black hole at the center of
our milky way galaxy sagittarius a star
they haven't yet released an image of
this black hole but this simulation
shows what it might look like it's much
closer at around 26 000 light years away
but also much smaller with a mass only 4
million times that of our sun
it's also less active only periodically
gobbling up matter and it would have
much more variation over time with
matter orbiting every 4 to 30 minutes
that's probably why we'll have to wait a
little longer to see the black hole at
the center of our galaxy
for now the striking image of the black
hole in m87 confirms beyond a shadow of
a doubt that black holes do exist
the general theory of relativity
published over a hundred years ago is
supported again in spectacular fashion
in the strongest gravities and at the
limits of our ability to test the theory
what i love about moments like this is
the ridiculous extreme things these
scientists did these 200 scientists in
pursuit of a goal that seemed impossible
and yet they achieved it
i want to extend my personal
congratulations to everyone on the team
for an amazing discovery i'll be linking
to all their work in the description
you