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The challenge is growing these smaller black holes quickly enough to make the much larger black holes we see a few hundred million years later. It turns out to be difficult because there are limits on how fast they can accrete matter. These should make sense to you from what we discussed earlier in the chapter. If the rate of accretion becomes too high, then the energy streaming outward from the black hole’s accretion disk will become so strong as to blow away the infalling matter.

What if, instead, a collapsing gas cloud doesn’t form a black hole directly or break up and form a group of regular stars, but stays together and makes one fairly massive star embedded within a dense cluster of thousands of lower mass stars and large quantities of dense gas? The massive star will have a short lifetime and will soon collapse to become a black hole. It can then begin to attract the dense gas surrounding it. But calculations show that the gravitational attraction of the many nearby stars will cause the black hole to zigzag randomly within the cluster and will prevent the formation of an accretion disk. If there is no accretion disk, then matter can fall freely into the black hole from all directions. Calculations suggest that under these conditions, a black hole even as small as 10 times the mass of the Sun could grow to more than 10 billion times the mass of the Sun by the time the universe is a billion years old.

Scientists are exploring other ideas for how to form the seeds of supermassive black hole    s, and this remains a very active field of research. Whatever mechanism caused the rapid formation of these supermassive black holes, they do give us a way to observe the youthful universe when it was only about five percent as old as it is now.

Key concepts and summary

Quasars and galaxies affect each other: the galaxy supplies fuel to the black hole, and the quasar heats and disrupts the gas clouds in the galaxy. The balance between these two processes probably helps explain why the black hole seems always to be about 1/200 the mass of the spherical bulge of stars that surrounds the black hole.

Quasars were much more common billions of years ago than they are now, and astronomers speculate that they mark an early stage in the formation of galaxies. Quasars were more likely to be active when the universe was young and fuel for their accretion disk was more available.

Quasar activity can be re-triggered by a collision between two galaxies, which provides a new source of fuel to feed the black hole.

For further exploration

Articles

Bartusiak, M. “A Beast in the Core.” Astronomy (July 1998): 42. On supermassive black holes at the centers of galaxies.

Disney, M. “A New Look at Quasars.” Scientific American (June 1998): 52.

Djorgovski, S. “Fires at Cosmic Dawn.” Astronomy (September 1995): 36. On quasars and what we can learn from them.

Ford, H.,&Tsvetanov, Z. “Massive Black Holes at the Hearts of Galaxies.” Sky&Telescope (June 1996): 28. Nice overview.

Questions & Answers

why are the hyperlinks not working?
Gregory Reply
If the atmosphere blocks the view of Venus' surface, what am I seeing that looks like craters?
Michael Reply
clouds?
Michele
If the surface of Venus is shrouded by white clouds, making it impossible to see the surface, what looks like craters when view the planet?
Michael Reply
I don't Know! perhaps the mountains?
Michele
my question is if the surface of Venus is shining y not our earth
Tahir
when we look at venus we can't see any crater like things... check it once again
RIEM
and venus shines because of the clouds that are made up sulpher dioxide and sulphuric acid droplets. and the clouds are so dense. the case of earth is different
RIEM
also because of Venus's 70% albedo phenamenon
Shivam
and plus it reflects 70 percent of its light back into space earth don't shine because it's not a cloudy planet and its farther than the sun
americantuber
can I become an astronaut without taking mathematics as a subject in 11th class
UNIVERSAL Reply
If the surface of Venus is shrouded by white clouds, making it impossible to see the surface, what looks like craters? Are these atmospheric storms?
Michael
can a death of a massive star be the new big bang
Neeta Reply
No it might be a supernova. The big bang was much more massive.
Nick
It created the universe as we know it
Nick
the big bang is just a new beginning
Neeta
the death of a gigantic star makes it possible for a new begging
Neeta
Only in the local area of space
Nick
so many smaller universes are created and destroyed
Neeta
i think it created a supernova!
Michele
you still think? I am sure I created one supernova of my own
Neeta
I'm sure you did
Nick
neeta the death of a massive star could lead to an explosion that leads to a super nova and when the supernova explodes it becomes a nebula like messier 1
americantuber
a supernova remnant
americantuber
what is means by earthbound
Satyam Reply
you are earthbound, arnt we all earthbound? except the ISS etc.
Collins
I don't agree we may be earthbound because of our gross body/physical body...but there is also a subtle body which does not limit us to earthly existence
Neeta
good questions, as humans our habitat is earth, we are bound to this and have to alter ourselves to stay alive off land and outside the atmosphere, do you not agree? I'd guess you could also say the moon is earthbound. anything earthbound is restricted to earth. hope this helps, love your question
Collins
how do you describe astral projection
Neeta
Astral projection is spiritual. I'm assuming Satyam was talking about the physical world.
TheDirtyGhost
ah yes spiritually we are bound only to what we chose, like nothing, I like to think that way
Collins
anyone here also participating in seti@home?
dreamer
what is seti?
Mahesh
what has extraterrestrial entity got to do with this why @seti project..we are discussing human existence on earth and beyond earth
Neeta
please join me at the cosmic Diner where all your intergalactic dreams come true.
Alba
I was just thinking what if somebody ignorantly mistaken a cosmic microwave Background with a conventional microwave we be in a lot of trouble.
Alba
don't kno
dreamer
You mean the Restaurant at the end of the Universe...right we can come back and visit again but not sure of the mode of payment
Neeta
yeah I'm already heading there
dreamer
how to read stars
Amresh Reply
you don't
Max
astrology i guess
Uttam
astrologer is the study of star systems and constellations...but astronomy is the study of formation of universes multiverses birth and evolu of stars
Neeta
cool
Uttam
what is astronomy
babul Reply
study of formation evolution and the death of star star systems and galaxies
Neeta
astronomy is the study of universe
UNIVERSAL
astronomy and physics are basically the same except physics is the study of the motion and behavior of the universe
americantuber
What is 12 constellation of zodiac and why it is important to study astrology
MUHIBULLAH
And also what is main purpose of these 12 constellation of zodiac in astronomy
MUHIBULLAH
astronomy and astrology with two different things
Deja
it Is the study of universe and of life speaking generally! i think!
Michele
universe is born 13,7 miliardi of years with big Bang if i remember well! but there are also other theories for the universe, speaking generally! i remember so!
Michele
universe is actually about 13.7 billion years old
Nick
is astrology like astronomy
debjani Reply
Astrology is a lower dimension.. astronomy is much more vast and multidimensional
Neeta
yes.. astrology is about constellations only, and astronomy is about all stars, galaxies, gravity, dark matter, dark energy.. etc everything including astrology
Mahesh
can you become an astronaut without taking mathematics as a subject in 11th class
UNIVERSAL
I was reading the chapter on Cosmic Microwave Background. And, I can not seem to find it now. If anyone could help me find that portion of the Astronomy Textbook I would really appreciate it. AZ
Alba Reply
Where or which chapter discusses Cosmic Microwave Background?
Alba
29.4
Andrew
29 the big bang ch 29.4
Andrew
yes
pratham
interesting
Orlando
what's cold dark matter?
pratham Reply
How are Roche Worlds formed?
AlteredEdge Reply
In need to read some books about Astronomy so how can in get it actually leg live in Ethiopia can uh help me with that?
Mom Reply
I am sri Sharan .m .what is my best favourable numbers
Madhesh Reply
how can we know it
sruthi
😂😂
Rango
bahut hard
Rango
Why no object can travel with speed greater than light?
geometry Reply
Because the mass of light particles is zero
Asim
Can mass be negative?
geometry
No
Asim
anybody stated that the light is the only thing is speed
sruthi
geometry are you a korean or kpop fan
sruthi
in this universe anything can be faster than light because we simply can't get to an conclusion
sruthi
I am a an Army but lets not bring spam here.
geometry
But why mass can't be negative. What I mean is how can we claim an object made of strange matter has positive mass. In other words, theoretically can negative mass exist?
geometry
in our observable universe nothing is faster than the speed of light
Rango
Thanks
geometry
But theoretically, is it possible? Sorry I'm being very curious..
geometry
I don't know about dark matter but may be you should think about dark matter because dark matter are really strange
Rango
Exactly so theoretically, an dark matter lazer can be greater in speed. Also maybe quartz..
geometry
may be but i am not sure about quartz and btw techyons travel faster than light but techyons are hypothesized
Rango
there are many objects which are perceived to be faster than light
Ganeshan
The object have their own declination rate in speed,the air friction can develop higher temperature resulting the object to be disappear in molecules,not considering the Physical conditions in space.The object should be unaffected with the air friction and also speed should proportionate with fuel.
Near
the early universe expanded faster than the speed of light. Consider, at the speed of light in vacuum, time stops.
Robert
Does this mean something moving beyond the limit experiences negative time?
Robert
Under such conditions, would matter exist as wave-fronts?
Robert
When examining a cosmology it is possible to find quite unbelievable conditions. I like to imagine life at the tip of an asymptote, but to surpass it seems perilously remote.
Robert

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Source:  OpenStax, Astronomy. OpenStax CNX. Apr 12, 2017 Download for free at http://cnx.org/content/col11992/1.13
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