hey guys welcome to my channel science
Jr.
today we are going to learn about a
fascinating phenomenon in space called
black holes
so let's start it
black holes are really amazing things
found in space
so before learning about black holes we
should first
understand how stars work all stars work
on a basic principle called nuclear
fusion
in which star exerts high heat and
pressure on to its atoms present in it
and it fuses them like it fuses hydrogen
atom present in it
into helium helium into oxygen and so on
in this process a lot of energy is
produced which opposes the stars gravity
and keeps its stable but
as the atoms fuse into heavier atoms at
one point iron atoms form
and there is a big problem with the
iron atoms
it can't be fused into heavier elements
so ultimately star is not
able to produce energy and collapse
under its own gravity if the star is
small
it will collapse into a planetary nebula
if the star is large
they will burst into a beautiful
supernova
if the core left is small then it would
eventually compress into a neutron star
and if the core is large enough then it
will compress
and form a black hole it can even pull
light into itself it has a mighty
gravity
this is how a black world is formed so
now we
uh answer some questions regarding black
question one
what do black holes look like
because black holes even put light into
them so we can't see them without naked
eye or
telescope scientists use different
instruments to look for black holes
if you want to know the names of the
instruments in scientists use
so please check out the description of
this video
if black holes pulls light into themselves but how do
scientists know they are there
as the paper says black holes can be
detected by watching for motion of stars
near them
stars act differently near the black
holes as the black hole pulls light
pulls light or bends the light of the
stars also
question 3 how big are black holes
oh yeah there are three types of black
holes small black holes stellar
black holes and super massive
there can be the smallest black hole can
be up to the size of an atom but have a
mass of a mountain
scientists think they are many and next
is stellar black hole stellar black holes
can have a mass of about
20 suns scientists think there are many
black holes in our
stellar black holes in our own galaxy milky way  and the last is
super massive all the supermassive black
holes are present in the center of the
galaxies
they are huge their mass
it has a mass of about four millions
4 million suns really!!
question 4 will our sun turn into a
black hole
in short no don't worry about that our
sun will eventually
turn into a white drawf
we'll explain about
white drawfs in
detail in our next video question 5
what happens when a black hole dies
as stephen hawking says the black holes
would evaporate
by time passes in the
during the evaporation they would emit
energy such as positive particles as they lose mass
loss mass as the time goes off
they become small and unstable
i hope that you have learned about black
holes today
but wait wait wait before leaving let's
answer a question about black holes what
happens when two black holes collide
when two black holes collide or come
near each other they emit
large gravitational waves and if one
black hole is big and one black hole is
small the bigger black holes swallows the
small black holes and increases in mass
it produces a large amount of
gravitational waves which can be
detected
till earth also so this is what happens
when two black holes collide
a very dangerous event happens
thank you guys for watching this video
and i think you have learned
about black holes much so if you have
any questions regarding black holes
please comment them down and if you have
any ideas for our upcoming videos
please comment them down okay thank you
stay safe stay healthy and be at home
