Why are most quasars so far away?
There is a greater volume of the universe that is far away than is nearby and quasars were more abundant in the past when galaxies were close together
. This image shows four quasars around a galaxy. The redshift of each of the four quasars is 0.0394 and greater than that of the galaxy.
What evidence indicates that quasars occur in distant galaxies?
Red shift and variability
provide evidence that quasars are at the centre of distant galaxies.
Which of the following is not a property of elliptical galaxies?
Terms in this set (15) Which of the following is not a property of elliptical galaxies?
They have prominent spiral arms
. When two galaxies collide, what happens to their stars?
What evidence do we have that quasars are small quizlet?
What evidence do we have that quasars are small?
They have rapid fluctuations in brightness
.
Why do we think that active galaxies have small core regions quizlet?
Why do we think that active galaxies have small core regions?
Their light varies rapidly, implying small radius
. … A massive object that bends the space around it, causing light to bend. Our Milky Way is part of _________ which has about ____ member galaxies.
Are quasars black holes?
Quasars are highly luminous objects in the early universe, thought to be
powered by supermassive black holes
. This illustration shows a wide accretion disk around a black hole, and depicts an extremely high-velocity wind, flowing at some 20% of light-speed, found in the vicinity of JO313-1806.
What causes a quasar?
If material falls into the accretion disc around a supermassive black hole it gets heated by friction and gravitational effects to the point
where it emits huge amounts of energy. This is a quasar. … The quasars which have been observed are in young galaxies millions or billions of light years away.
What are 3 characteristics of an elliptical galaxy?
There are four distinguishing characteristics of the ellipticals: (a)
they have much more random star motion than orderly rotational motion
(star orbits are aligned in a wide range of angles and have a wide range of eccentricities); (b) they have very little dust and gas left between the stars; (c) this means that they …
When two galaxies collide what happens to their stars?
Merging galaxies can also
trigger the creation of new stars
. Galaxies are also composed of gas and dust. The gravitational pull of both colliding stars can interact with this materials, creating friction and shock waves that can ignite the formation of new stars.
How old are the stars in an irregular galaxy?
The main body of SagDig is rich in gas, and contains many regions of active star formation. Indeed, the average age of the stars in the galaxy is a relatively young
4 to 8 billion years
.
What two things does the engine of a quasar contain?
The engine of a quasar consists of
a supermassive black hole and a ready supply of gas and dust
.
What causes the redshifts we see in spectra of quasars quizlet?
What causes the redshifts we see in spectra of quasars? The spectra of quasars are redshifted
by the expansion of the universe, rapidly increasing the distance between the quasars and the Milky Way
. … If the universe was infinitely old, light from stars at the end of every line of sight would eventually reach you.
Why does the Milky Way look like a band in the night sky?
This band of stars can be seen with the naked eye in places with dark night skies. That band comes from seeing the disk of stars that forms the Milky Way from inside the disk, and tells us that
our galaxy is basically flat
.
What holds the galaxy together quizlet?
What holds galaxy groups together? In our solar system
gravity
holds everything together. And stars then cluster together.
What causes nearly all spiral galaxies to have flat rotation curves?
A galaxy’s rotation velocity and size are needed to figure its mass. What causes nearly all spiral galaxies to have flat rotation curves? … Rotation curve-
a plot of orbital velocity for stars and gas clouds versus distance from a galaxy’s center
.
Why do we think that quasars are extremely distant?
Why are most quasars so far away?
There is a greater volume of the universe that is far away than is nearby and quasars were more abundant in the past when galaxies were close together
. This image shows four quasars around a galaxy. The redshift of each of the four quasars is 0.0394 and greater than that of the galaxy.