- 4020 - BLACKHOLES
- monsters or creators? Blackholes are those monster gravity sink
holes in outer space that swallow everything that comes near them and devours
them forever, or ?????
------------------------ 4020 - BLACKHOLES - monsters or creators?
- Or, Blackholes are
the creative forces that formed the unique galactic structure of our
Universe. We would not exist without
them.
-
- Which is it,
Blackholes the agents of destruction , or, the pillars of creation?
-
- Blackholes have so
much gravity that even light photons can not escape the pull and everything is
pulled inside to a singularity of infinite density.
-
- Blackholes were for
a long time in theory only. No evidence
could be found for their actual existence.
Evidence was found where objects had so much mass and so little volume
they could theoretically only be a Blackhole.
They were first thought to be rare occurrences. Today, not so. We think massive Blackholes are at the center
of galaxies and that small Blackholes are common
-
- The oldest
Blackhole found to date is 13 billion lightyears away. So, what we observe happened 13 billion years
ago. It took that long for the light to
reach us. If it still exists today, that
is how old it is. The Big Bang happened
13.7 billion years ago. Therefore within
1 billion years after the Big Bang Blackholes were forming.
-
- After the Big Bang
the first stars formed were 100 times more massive than our Sun. They burned all their fuel in less than 1
million years and exploded. When these
giant stars went supernova their cores were so big their gravity collapsed all
matter into a super dense Blackhole.
-
- Blackholes were
closer together back then in the early Universe so mergers happened quite
frequently. Blackholes grew to 1 billion
solar mass by 840 million years after the Big Bang.
-
- Astronomers can not
see Blackholes, obviously. What they can
see it the brilliantly hot gases swirling around in the accretion disk before
the gas gets sucked in by the enormous pull of gravity. Surrounding these hot accretion disks were
star forming galaxies.
-
- Visible matter
alone in the galaxies could not account for their structures. Invisible matter at least 10 times more
massive must exist surrounding the galaxy for the math to work out. The invisible matter is called Dark Matter.
-
- Galaxies collided
and merged into bigger galaxies. The
bigger galaxies became even more star friendly because the mergers created
shockwaves through space that compressed dense clumps of gas triggering star
birth.
-
- Our Milky Way
Blackhole is Safittarius A. It weighs
4.5 million solar mass. If you get
within 10 million kilometers ( 6.2 million miles) of this Blackhole time begins
to slow down, light reddens, and dims until you pass the Event Horizon and are
frozen in time, gone forever.
-
- At the Event
Horizon General Relativity and Quantum Mechanics predict different results
leaving a mystery of what physics to apply to understanding what is inside a
Blackhole. Physicists are inventing new
math to bring Relativity and Quantum Mechanics together, called Quantum Gravity
and String Theory, and other theories.
-
- Relativity can
completely characterize a Blackhole with 3 simple numbers, its mass, its
charge, and its spin.In falling gas and dust create energy and radiation
greater than anything known.Energy that is 20 times more powerful than nuclear
fusion. In this way Blackholes are the
brightest objects in the Universe.
-
- Enormous magnetic fields are created by
the swirling charge particles in the accretion disk. In some mysterious way jets are created and
shot out of the poles at 99.98% the speed of light. These jet beams are tightly collimated and
travel distances greater than the size of galaxies.
-
- A 15 solar mass
Blackhole would have an Event Horizon of only 90 kilometers ( 56 miles). A billion solar mass Blackhole would have an
Event Horizon that would fit inside our Solar System. Material circling a Blackhole is traveling so
fast it completes one orbit in a microsecond, 0.000001 seconds.
-
- Astronomers
determine the mass of Blackholes by measuring the orbits of stars near it. They measure the orbital velocities of the
accretion disks by the shift in the florescence of iron atoms on the surface of
these disks. Velocities range close to
30% the speed of light.
-
- When Blackholes
collide and merge they shake the fabric of spacetime crating gravity waves like
ripples on a pond. Astronomers are
detecting these waves using massive laser interferometers.
-
- Besides Sagittarius
A to study there is another Blackhole in M87 that is 55 million lightyears
away. It is 6.4 solar mass with jets
extending out 5,000 lightyears.
Sagittarius A is 24,000 lightyears away.
-
- One objective is
to image these Blackholes through gravitational lensing of light that is behind
the Blackhole and gets bent by the gravity as it passes by. But getting this image would be like taking a
picture of a poppy seed in L.A. looking at it from New York.
-
- To see something
this small we need larger telescopes operating at smaller wavelengths. Infrared wavelengths pass through the dust
clouds so they have an advantage over visible light. Infrared telescope would have an angular
scale of 55 micro arc seconds and need to be 7 kilometers in diameter. Not too
practical. Using millimeter radio waves
it would require a telescope 5,000 kilometers in diameter.
-
- But, radio
telescopes located around the globe could do just that. We just need to connect them together to a
single computer to create an interferometer with antennas 5,000 apart. It is called a VLBI, very long baseline
interferometer. When these are working
we should be able to image a Blackhole from the gravitational lensing of light
directly behind the Blackhole. Studying
these images should unlock many of the mysteries of Blackholes. In turn, we should learn more about the
creation of the Universe. What do you
think could astronomy do such a thing?
-
May 23, 2023 BLACKHOLES - monsters or creators? 1096 4020
-------- Comments appreciated and Pass it on to
whomever is interested. ---
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for
copies or Index of all reviews
--- to:
------
jamesdetrick@comcast.net
------ “Jim Detrick” -----------
--------------------- --- Wednesday, May 24, 2023
---------------------------------
-
No comments:
Post a Comment