a

In Search of Sagittarius A* - SUPERMASSIVE Black Hole [Space Engine]

welcome to our beautiful planet Earth I

believe this is South America but we're

not actually going to be looking at

Earth today we're going to go out there

into the into our galaxy into Milky Way

and try to find something really really

important for our galaxy and that's

something that I'm talking about is of

course Sagittarius a now this video is

called in search of Sagittarius a

because we're going to be looking for

this really really massive black hole

somewhere in the center of our galaxy

that essentially everything in our

galaxy orbits around including of course

our Sun our Sun actually is currently

orbiting around Sagittarius a now

Sagittarius a is not a particularly

exciting name for this black hole so

actually at the end of this video I'm

going to try to give it a much better

name and if you have a much cooler name

that we can assign to it sometime in the

future do post it in the comments though

anyway welcome to what the math and

enjoy the video

and to find Sagittarius a we're only

going to be using space engine today

because I figured it's about time that I

just spend time with this really really

awesome simulator that a lot of you have

been asking about space engine as you

mean actually know is absolutely free

and unfortunately it's only available

for Windows but if you do have Windows

or you can emulate Windows on your Mac

you should definitely get this because

look at the beauty that it creates this

is a by far the best space simulator out

there

hands-down I'm sorry universal box -

you're great but you know nothing beats

free and this is definitely amazing

anyway so how are we going to actually

look for this amazingly huge massive

black hole especially considering the

fact that you can really see black holes

they're you know they're black that

that's why they're called black holes

there you cannot really see them you can

only see the after-effects and so as I'm

actually moving closer to the center of

our galaxy faster and faster and you can

kind of see the stars swimming swimming

by us as I'm approaching the center of

our galaxy I'm just going to tell you a

little bit more about how this

particular black hole was detected and

it's actually not not very tricky as a

matter of fact the reason we actually

are almost 100% sure there is a black

hole right at the at the point where I'm

going is because of another star a very

very large star about 15 masses of our

Sun that is actually relatively bright

as well that orbits around this

imaginary or invisible point and you can

kind of actually see or we've actually

seen it orbit around that point and its

orbit only takes it about 15 years so

there's this star somewhere in the

middle and it's actually it's just

called s 2 and s 2 and you can actually

see the picture here that shows you the

orbits of all of these stars and so the

orbit of s 2 and only takes it about 15

years and it's really interesting

because it actually moves really really

fast at about five thousand kilometers

per second and at this speed it's it's

impossible for it to be anything else

but a very very massive black hole that

creates this kind of

now all right so that's good so we know

that there's a black hole somewhere here

but unfortunately because it's as you

can see it's really really bright here

it's actually almost impossible for us

to detect it so we can only see it using

the effects of other stars or basically

seeing the orbits of other stars and

then trying to estimate where exactly

it's located but anyway we'll never

really find it if we just fly around our

galaxy we just have to do this a little

bit differently we're going to actually

click on this button right here and this

allows us to search for various objects

and within a certain distance so let's

actually look for everything that is a

black hole within the radius of about 10

light-years from us so we're going to

actually just click on OK here and then

click on search and well looks like

there's nothing around us however if I

change this to 100 light years if we

actually increase the search radius we

will be able to find look at that at

least three different black holes now

how do we know if this is the actual

black hole we're looking for and the way

you can tell is usually by the number of

stars orbiting around it so this one

seems to be pretty massive so let's see

if this is what we're looking for

although I'm pretty sure it's not but

we're actually just going to go there

and check it out

so I think this is one of the black

holes nearby but it's probably not the

one we're looking for and by clicking on

this button right here I can actually

see that this is not a black hole I'm

looking for it as a matter of fact this

is a binary system where there is a

brown dwarf and a black hole having a

berry Center and this particular black

hole is only about 10 times the mass of

Suns it's actually very very small in

comparison to these Sagittarius a which

is 4.3 million times of our Sun which is

actually much much much more massive so

right let's try this again them and

having searched again using thousands of

light radius I found a few more black

holes but once again none of these are

actually massive enough enough for us to

actually consider them to be Sagittarius

II but you can see there's actually

quite a lot of black holes within

thousand light-years of this particular

location so they're not very uncommon is

it they're actually pretty common all

right so that's good let's actually try

to go a little bit more in

in the middle of the of our galaxy and

search again but this time we're going

to increase the radius to about ten

thousand light-years so I'm actually to

do this even more effectively what I'm

going to do is I'm going to fly out of

the galaxy just to see where

approximately where the center is and

it's actually somewhere in here so and

then we're going to just very gently

approach the center and right in this

location as you can see there's a lot of

stars this is a very highly concentrated

area and we're going to search for it

again using the same principle and we

found a lot more black hole here at the

center but if you look at the if you

certain by stars if you look at this one

this has 23 stars alright so that looks

really interesting so let's actually go

to this particular black hole we're

going to go to it and see if this is

actually what we're looking for and what

my god look at the size of that thing

this is already very very large look at

the great ational lens and in fact that

it even creates and so this is a pretty

massive black hole if I actually click

on it

you'll notice that it says that the mass

here is not even listed as a matter of

fact if I actually click on this object

it says galaxy Milky Way and if I were

to right click and info it it says this

is the Milky Way so essentially this is

the center of our galaxy and we were

able to easily find it just by going

into an approximate location of a center

and then looking at all of the black

holes within thousand light-years of

that location now there's another one

here and it's a pretty massive black

hole as well and there is actually

another black hole orbiting around this

central black hole and that other black

hole is actually quite massive as well

it's about 1,300 times the mass of our

Sun and it was discovered in 2004 by a

group of scientists and what's really

interesting about the other black hole

that orbits around this central large

black hole is that it actually shows us

or it gives us an idea of how these

massive black holes at the center of the

galaxies are formed so what scientists

think today is that the other black

holes that orbit around it eventually

gets sucked into it and increase its

mass and this sort of gives you an idea

of how all of

galaxies are created so in the beginning

this might have been a very small black

hole but as it absorbed more and more

massive black holes from vicinity it

basically became an ultra massive black

hole that it is today and what's really

interesting about the Sagittarius a is

that we know that it has an accretion

disk so there's a Christian disc that

has a distance or it basically orbits

around the black hole at a distance of

very close to the orbit of Neptune in

our solar system so it basically it's a

very very large very wide arc and this

accretion disk actually emits radio

waves that we can receive from Earth and

we actually know that there is something

going on here that's very likely an

accretion disk from a black hole because

of this radio wave emission that we we

can actually hear on earth and what's

even cooler is that once in a while

we'll even detect some crazy crazy x-ray

emissions a really powerful x-ray

emissions from this region and the only

explanation we have for those x-ray

missions especially the one we actually

were able to detect in January of 2015

is that something like an asteroid or a

small planetoid probably smacked right

in the middle or basically approached

this location and fell into the black

hole and then as a result of the

collision with the black hole it emitted

a very very large amount of energy and

there's quite a lot of these x-ray

missions that have been detected because

we're actually always looking in this

direction there's actually a telescope

that is always monitoring this black

hole just looking for more stuff to

discover and more unusual things to to

see and actually one of the cooler

things that they saw relatively recently

started in 2008 was what you see on the

screen right now they actually were able

to see a cloud of gas passing by very

close to this location and getting sort

of disrupted by it and there's an artist

rendition of what possibly happened

I think people or a scientist basically

think that it may have been a star that

approached the black hole really really

closely and it just got broken up into

little pieces because of what's called a

Roche limit and also because of the fact

that there's a very strong gravitation

here and so as this object approached

the

code get broken up into pieces and

basically created the cloud that we got

to detect now what I wanted to see is

actually this I wanted to accelerate

time and just watch these stars that are

close to it

orbit around it and you'll actually see

that they orbit really really fast so

we're going to accelerate time so that

it's it's possibly something like one

month per second there we go and you can

see how fast they orbit so there is our

stars and these are actually don't have

the same names as they do in real life

but these are the stars that we can

actually see orbiting around this

imaginary location in real life as well

so there we go this is a little bit

better this is maybe four months per

second and there we go and there's

actually a lensing effect that you can

detect in space engine but unfortunately

we cannot see the lens and in fact from

Earth because like I mentioned before

there's so many other things in between

this black hole and our planet Earth

that we just can't really see it very

well it's a little bit difficult to see

but our planet is not is not actually

that far away from it so only about

26,000 light-years away and one orbit of

our star our Sun takes several hundred

million years or actually I believe it's

hundred fifty million years around

around there whereas these stars they

orbit really fast so the fastest one is

fifteen years

I think this lowest one is maybe about

35 years but they all are basically

orbiting around this very very massive

black hole and they're doing it really

fast now because it's not really even

close to the speed of light they're

obviously not going to experience

anything close to what you we saw in the

movie interstellar so interstellar was a

little bit far-fetched that's the this

has to be a supermassive black hole that

also spins really fast to create time

dilation effects that we get to see in

interstellar but here the time dilation

effects would be very very minor so even

on the fastest star you would only maybe

gain a few seconds per for every few

years in other words if you were to live

on a planet that orbits one of these

stars which like let's just say this

star right here

and so if you were to live on one of the

planets that orbits this star you would

possibly gain maybe a few seconds for

every few years and so if you lived here

and your twin lived on earth you would

actually be a few seconds younger every

few years than your twin and that's what

we call time dilation and so as we're

orbiting around this black hole which is

somewhere here there it is it's right

there in the middle I'm gonna try to

zoom into it so you can get to see it a

little bit better there we go so as

we're orbiting around it you can kind of

see that not only is there a really

interesting motion of other stars that

is going on around around it but you can

also see it from from this distance you

actually get to see a very strong effect

of the gravitational lensing that is

created by this supermassive object now

one thing I forgot to mention is the

size of this black hole the way we

measure black holes is usually with

something called Schwarzschild radius

which refers to the I'm going to come

close to it so I can show you the radius

of this right here so this is what we

call event horizon this is the area

where we don't really know what happens

after like nothing actually weaves event

horizon even light cannot escape it and

on this radius right here this is where

escape velocity is basically equal to

the speed of light it's close to 300,000

kilometers per second and so this radius

from the center to here is approximately

12 million kilometers so that's about

1/4 of the orbit of mercury or about 17

times the radius of our Sun so it's not

very large but at the same time it is

very very massive and it is obviously a

very scary and a very powerful object so

there's a lot of energy involved here

and there's definitely a lot of things

going on that we are not even certain

about yet because this is essentially

what our entire galaxy orbits around and

so oh no this is actually a pretty

awesome object I mean it's actually so

awesome that I'm really surprised we

don't have a better name for it yet and

unfortunately because this object

actually has no cool name yet I think

one of the better names for it would be

Chronos Chronos is of course the elder

god in Greek mythology who is known for

eating his own children and is actually

a very famous painting that depicts him

in his own child and it obviously also

means time it also represents time and I

think it's a pretty good description or

a pretty good analogy to what a black

hole is and we're gonna come really

really slowly to it so you get to see

how everything changes as we come closer

to it but if you actually have a much

better or much cool sounding name that

is relevant to Greek or Roman mythology

because it's actually it's the

astronomical convention it has to be

from one of the mythologies it can be

Norse mythology it can be Slavic

mythology it can be any kind of

mythology but it has to be a deity or a

god that is basically from one of those

mythologies and if you have a really

cool name that sort of applies to a

black hole and as we're basically

approaching event horizon this is how

everything around us will change but

yeah post it in the comments below

please and thank you and obviously I'm

not sure if one day someone will

actually name it that but you never know

because people are watching this channel

and maybe they'll like our idea anyway

so do post your suggestions in the

comment box and as we land on the event

horizon you'll actually get to see what

you would see if you were to approach a

black hole really really slowly and then

land inside of it and what happens after

is anyone's guess that's probably one of

the mysteries we still haven't been able

to resolve even today anyway I hope you

enjoyed this video and I hope you

learned something about the black hole

in the center of our galaxy and as we

learn on it you'll notice that we start

orbiting really really fast I'm actually

going to slow down time now because

what's happening now is that the black

hole is spinning really fast and because

it's spinning and because it's spinning

you get to see these really really crazy

effects on on the surface of this black

hole anyway so thank you so much for

watching please subscribe if you still

haven't and like this video if you've

enjoyed watching it and don't forget to

share it with someone who you think may

want to learn more about astronomy and

astrophysics and once again thank you

for watching game you guys later I'll

see you next video and as always bye-bye