Double Your Science: Starburst Galaxies Found with Active Quasars
Written by Fraser Cain
Astronomers now know that essentially every galaxy has a supermassive black hole at its center. When the black hole is actively feeding on material, the surrounding region can blaze brightly - this is a quasar, aka an active galaxy. The Hubble Space Telescope has been used to image a set of exotic active galaxies, known as post-starburst quasars.
What's the relationship between galaxies and their supermassive black holes? Astronomers have been trying to work that out since these monster black holes were first discovered. One theory is that the growth of both go hand in hand through successive galactic mergers. Each merger adds new stars to the galaxy, as well as additional mass to feed the black hole.
With the galactic mergers, there are intense periods of new star formation. Gravitational interactions collapse clouds of gas and dust that go on to form stellar nurseries. The new star formation is hidden in the beginning, but the active quasar at the middle of the galaxy blows with a powerful wind that eventually blows out the obscuring dust.
Starburst galaxies aren't bright for long, because all the hottest, most-luminous stars only last a few million years before detonating as supernovae. Astronomers were hoping to see galaxies right in the middle, where starburst activity is fading, at the same time that the quasar is blasting out radiation.
One transition galaxy like this had been discovered in the late 1990s. It possessed both the characteristics of a quasar and an older starburst galaxy. At the time it was discovered, the starburst period had happened 400 million years ago - that's why it's a post-starburst galaxy.
An international team of researchers used the Hubble Space Telescope to find another 29 examples of these post-starburst quasars. They searched through a candidate list of 15,000 quasars, and found the signatures of 600 post-starburst objects. With ground-based telescopes, these would just be smudges, but the full galactic shapes can be seen in the Hubble images.
Our galaxy will be colliding with Andromeda in about 3 billion years. When this happens, the Milky Way will burst with star formation. One day, we'll be living in a post-starburst galaxy.
Original Source: Hubble News Release
Filed under: Astronomy, Black Holes, Hubble
June 2nd, 2008 at 5:44 pm
"One day, we'll be living in a post-starburst galaxy."
Not I. I plan to be dead in roughly 60 years. I think I'd get bored waiting around for the fireworks…
June 2nd, 2008 at 10:55 pm
I do plan to see that happen.
June 3rd, 2008 at 2:39 am
"I do plan to see that happen."
One way or another….I also!!!
June 4th, 2008 at 8:08 pm
Good luck waiting for that. Might as well wait for the Local Group to fall into the Virgo cluster.
June 30th, 2008 at 9:11 am
THE UNIVERSITY OF THE ABSOLUTE
112 North Mills Street
Apartment 210
Madison, Wisconsin 53715
ATTENTION: To whom it may concern
It is known that planet earth accretes of matter and if the
accretion so phenomenal then it is clear that planet earth does
slowly grow! Another thing is know…the solar PROMENENCES do
circulate. The PROMENENCES of the solar logos to move of their
great cycles moving away, repulsively, from the solar logotique
surface pushed away therefrom repulsively and motionally like
the cycloniques, but then, again, fall back into the solar surface,
this is observable! Of this way a great solar wind continues to
expand, some of it, into the great reaches of space…the all of this
is telescopically observable all then having of an interpretable
implication in the light of knowledge of the "phenomenalisms"
known?
Because of the GIANT SIZE of the solar logos (sun planet) being
disparitous of its great volume disparitous to the tiniest of the
growing planets; because of the great contrasts between of
these two different types of the cosmological volumes…it
becomes easy to know and understand that the volume of the
sun planet was once of a smaller planet having the volume that
of Mercury, of Venus, of Earth or Mars; but this is a discoverable
and an implicational fact? That planet Earth, upon a time, must
have been, at one time, a smaller volumed planet like Mercury
and Venus…that is to say; planet earth, like the planets Mercury
and Venus must have been "that" of a smaller planet as
well…this is the conceivable? One thing is clear…that the mighty
sun planet does matter accrete!
The electrique charges of the same kind do forcefully repel, this
is the phenomenally known…that the PROMENENCES of their
cycles do move of their motions propelled away from the surface
of the solar sphere, more then likely the occurrences of the
PROMENENCES that motion caused of them of an electrical
repulsion and that the PROMENENCES falling back to the surface
of the solar sphere the result of the dissipation of the electrique
charges had of the pushed away elements of the PROMENENCES
two body electrically repulsed and the dissipation of the electrical
charges had of the elements of the PROMENENCES then
gravitationally influenced to the return to the surface of the
electrified solar sphere.
It is clearly seen! The Earth planet, at this particular time, of its
history: is not, at all, lighted and powered like the sun and the
stars though it could become so?…the earth planet, at this
particular time, the earth is quite dark even though it could be
made to radiologically emit like the sun and the stars? It is clear,
to me: planet earth, like the sun and the stars…that they all do
matter accrete and that, similarly, like the sun and the stars, it
has become clear, to me, also that planet earth, like the sun and
the stars, may, similarly, become lighted and powered of an
electrical and of an industrial means?
Write, responsively, to me,
Respectfully,
William H. Millard
ON-LINE COSMOLOGICAL ELECTRICAL ENGINEERING
wmillard@earthlink.net