A Look at Space: Part 1: The Weirdest and The Mysterious

Originally posted by jp1111
In 1987, the brightest supernova of history was recorded and confirmed by Hubble Space Telescope in the Large Magellanic Cloud, our neighbor. The mirror-imaged rings of this exploding star still remain a mystery.

They are propably some old gas bubble which was ejected to space in some point of star's life in supergiant phase. And is now lighted by result of supernova. (like lighthouse)

And brightness of that ring (about 20000 year old gas bubble from older "explosion" ejecting stars outer layer) surrounding "star" should increase about thousand times in coming 10-20 years when supernova's shockwave collides to it with full power... so five years from now pics might look "little" different.

[edit on 17-8-2004 by E_T]

Originally posted by E_T
They are propably some old gas bubble which was ejected to space in some point of star's life in supergiant phase. And is now lighted by result of supernova. (like lighthouse)

I read about that too. However, the scientists are not certain. A few theories have been proposed for the creation of those rings. One of them says that the supernova, now a neutron star or a black hole, has a companion star from which it is stripping gas/matter away, heating up and spewing the material back into space with two jets along with radiation and thus creating a ring structure.

This thread is outstanding. I've enjoyed reading it.

One of the more fascinating concepts I have read and seen shows on recently has to do with the cosmological constant and the empty vacuum of space. A team of scientists from Berkeley were conducting research into supernovae. The lead researcher Dr. Saul Pulmetter...well, here's some background:

BERKELEY, CA -- By observing distant, ancient exploding stars, physicists and astronomers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory and elsewhere have determined that the universe is expanding at an accelerating rate -- an observation that implies the existence of a mysterious, self-repelling property of space first proposed by Albert Einstein, which he called the cosmological constant. This extraordinary finding has been named Science magazine's "Breakthrough of the Year for 1998."
The Supernova Cosmology Project, based at Berkeley Lab and headed by Saul Perlmutter of the Physics Division, shares the citation with the High-z Supernova Search Team led by Brian Schmidt of Australia's Mount Stromlo and Siding Spring Observatories. Both teams are international collaborations, with researchers in England, France, Germany, and Sweden among the members of the Supernova Cosmology Project.

Energy Secretary Bill Richardson expressed pride in the accomplishment on behalf of the Department of Energy (DOE), which funds the country's national laboratory system.

"This brilliant example of quality research by DOE-supported scientists represents an important advance in our understanding of the universe," Richardson said. "It's impressive payback, in terms of advancing human knowledge and developing promising new technologies, for this country's investment in basic science research."

Berkeley Lab Director Charles Shank concurs. "We are proud of Berkeley Lab's contributions to this dramatic accomplishment," he says. "This achievement is yet another example of how painstaking, imaginative, basic research can advance humankind's knowledge of our universe, with the promise of impacts on our lives that we can only begin to imagine." (See expanded quotes from Richardson and Shank.)

Says Perlmutter, "A DOE facility like Berkeley Lab is a unique place that brings together many different areas of expertise -- particle physicists, astrophysicists, computer scientists, and engineers were all vital to our program. Just as important, the Lab environment allows research to continue over a long time. We worked ten years before we finally got the answers to our questions."

A Special Kind of Supernova is the Key

The surprising discovery that the expansion of the universe is accelerating, and thus is likely to go on expanding forever, is based on observations of type Ia supernovae, very bright astronomical "standard candles" that all have the same intrinsic brightness. Thus how bright they appear reveals their distance.
By comparing the distance of these exploding stars with the redshifts of their home galaxies, researchers can calculate how fast the universe was expanding at different times in its history. Good results depend upon observing many type Ia supernovae, both near and far. Employing supercomputer facilities at the National Energy Research Scientific Computing Center (NERSC) located at Berkeley Lab, the Supernova Cosmology Project has fully analyzed the first 42 out of the more than 80 supernovae it has discovered, and more analysis is in progress.

Type Ia supernovae are rare -- in a typical galaxy they may occur only two or three times in a thousand years -- and to be useful they must be detected while they are still brightening. Before the Supernova Cosmology Project employed search techniques developed during the first five years of its existence, finding supernovae was a haphazard proposition, which made it difficult to secure telescope time to observe them.

"It was a chicken and egg problem," says Perlmutter. "To get telescope time, you had to guarantee you were going to find a supernova. But without time on a major telescope, it was impossible to show that they were there, and that we could find them." Then, in the early 1990s, the group developed a new strategy that assured discovery of numerous supernovae "on demand."

The fascinating part of their research was what could be going on in the vacuum of space that was previously thought to be empty. I don't remember the exact object they described but it apparently goes in and out of existence and is strong enough to accelerate the expansion of the universe despite the tug of ever present gravity.

It was old news but fascinating to me none the less. Finding out what those particles are and what their properties are could be an major breakthrough.

Sorry if this is outdated or amatuerish of me to even bring it up as a subject but I really find it to be one of the wierdest aspects of space. If anyone has any further info on it I would love to read some more. I'm just diving into this subject.

Thanks Weller for the article and the input. It is very interesting.

I think what you are referring here is the concept of dark energy. It is something that is thought to constitute around 73% of the universe! It is not outdated. They are still trying to figure out what the actual nature of dark energy is. It is one of the most mysterious concepts in astrophysics.

May be dark energy is just another aspect of gravity which we have yet to understand. It is thought that dark energy has always been present since the early years of our universe, but as the expansion is accelearating, gravity is weakening and thus the dark energy is getting stronger. Unless its nature changes with time, our universe will end up in a cold death (the Big Rip theory).

from: www.sciencenews.org...
What is this mystery force?

Cosmologists have proposed that it derives from dark energy�a substance whose properties and origin scientists have only begun to explore. At stake is more than just a better understanding of the fate of the universe: The very presence of dark energy may enable scientists to explain the fundamental forces of the universe and tease out the hidden connections among them.

Says Albrecht: "This is the most exciting endeavor going on in physics right now."

from: www.nasa.gov...
Probing dark energy, the energy in empty space causing the expanding universe to accelerate, calls for accurately measuring how that expansion rate is increasing with time. Dark energy is thought to drive space apart.

Astronomers used NASA's Hubble Space Telescope to hunt for supernovae (an energetic explosive event that occurs at the end of a star's lifetime), using their brightness, astronomers could measure if the universe was expanding faster or slower in the distant past.

In its search, Hubble discovered 42 new supernovae, including six that are among the most distant ever found. The farthest supernovae show that the universe was decelerating long ago, but then "changed gears" and began to accelerate.

Timeline:
external image
Possible fates of the universe that depend on the nature of this mysterious force:
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source: www.nasa.gov...

from: abcnews.go.com...
In February, the team published results of Hubble Space Telescope observations that spanned a range of distances and periods in the universe's history. They found the period, some 6 billion years ago, when the shift occurred from a slowdown in the rate of expansion to an acceleration � a turning point that has become known as the "big jerk." The team used the light from a powerful "standard candle" � a type of exploding star, or supernova � to gauge distance. Then they used spectrographic data on these objects to determine the speed at which the galaxies containing the supernovae were receding.

A third major contribution came last year from a set of studies involving the cosmic microwave background measurements from a NASA satellite and observations from the Sloan Digital Sky Survey. Both pointed to dark energy as the dominant ingredient in the universe's recipe. And by combining data from the two, four teams working independently found evidence for the action of dark energy on the scale of galaxy clusters, which cover a huge expanse of space and embrace from 50 to 1,000 galaxies.

from: www.pureenergysystems.com...
Recent theoretical explorations may suggest another approach to the physics of the vacuum. Some physicists have speculated that the invisible gravitating dark matter could be the other side of the invisible dark energy coin, and that suggests the possibility of manipulating the vacuum for energy release. If a controllable parameter could be found to mediate the balance between the invisible dark forces, the result would unleash the vacuum energy of creation in all of its awful power and majesty.

If it were possible to control the dark sides of the force then spacetime, the arena where everything we know takes place, could be bent and twisted with infinitely greater ease than was ever suspected. This would open Pandora's box to everything from vacuum energy weapons of mass destruction (capable of destroying the universe!) to spacetime warp drives and time machines.

Other Readings:
www.space.com...
www.space.com...
www.space.com...

Thanks for all the links and reading material jp1111! Very interesting, it helped fill in the holes.

As weller said thank you very much for the material jp111. This is an extordinairy thread, I spent a good amount of time browsing between the 3 in your signiture.

You're welcome, Weller.
You too Veda, no problem. I'm glad that you found it worth browsing through.

[edit on 27-9-2004 by jp1111]

Gravitational Lensing, a prediction of Einstein's GR theory, as seen in the images given below, is an effect caused due to the bending of light by the gravitational "pull" of matter. Visible matter is just not enough to create that effect, so the leading source has to be the mysterious dark matter, which is thought to constitute around 23% of the universe, where visible matter is only 4%, dark energy taking over the rest. The technique of gravitational lensing is very useful in determining the mass-density of galaxies.

Galaxy Cluster Abell 1689:
external image
Source: antwrp.gsfc.nasa.gov...
"Two billion light-years away, galaxy cluster Abell 1689 is one of the most massive objects in the Universe. In this view from the Hubble Space Telescope's Advanced Camera for Surveys, Abell 1689 is seen to warp space as predicted by Einstein's theory of gravity -- bending light from individual galaxies which lie behind the cluster to produce multiple, curved images."

Galaxy Cluster CL0024+1654:
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Source: antwrp.gsfc.nasa.gov...
"What are those strange blue objects? Many are images of a single, unusual, beaded, blue, ring-like galaxy which just happens to line-up behind a giant cluster of galaxies. Cluster galaxies here appear yellow and -- together with the cluster's dark matter -- act as a gravitational lens. A gravitational lens can create several images of background galaxies, analogous to the many points of light one would see while looking through a wine glass at a distant street light. The distinctive shape of this background galaxy -- which is probably just forming -- has allowed astronomers to deduce that it has separate images at 4, 8, 9 and 10 o'clock, from the center of the cluster. Possibly even the blue smudge just left of center is yet another image! This spectacular photo from the Hubble Space Telescope was taken in October 1994."

Galaxy Cluster CL2244-02
external image
Source: antwrp.gsfc.nasa.gov...
"It is difficult to hide a galaxy behind a cluster of galaxies. The closer cluster's gravity will act like a huge lens, pulling images of the distant galaxy around the sides and greatly distorting them. This is just the case observed in the above recently released image from the VLT. The cluster CL2244-02 is composed of many yellow galaxies and is lensing the image of a blue-white background galaxy into a huge arc. Careful inspection of the image will reveal at least one other lensed background galaxy appearing in red. The foreground cluster can only create such a smooth arc if most of its mass is smoothly distributed dark matter - and therefore not concentrated in the yellow galaxies visible. Analyzing these gravitational arcs gives astronomers a method to estimate the dark matter distribution in clusters of galaxies."

I will post more on this as soon as I'm done gathering more info.
Feel free to add stuff on this subject or any comments. Thanks.

- JP

The Lynx Arc: in the northern constellation Lynx
external image
Source: antwrp.gsfc.nasa.gov...
"The notably red 'Lynx arc' lies right of center in this color image of the galaxy cluster, a composite of Hubble Space Telescope and ground-based data. While the galaxy cluster lies about 5 billion light-years distant, spectroscopic studies show that the arc itself is actually a distorted image of an even more distant but enormous star-forming region. The image is formed as the closer galaxy cluster's gravity bends light like a magnifying lens, an effect explained by Einstein's theory of gravity. In fact, the monster star-forming region is nearly 12 billion light-years away and about a million times brighter than the more familiar stellar nursery, the Orion Nebula."

Galaxy Cluster Abell 2218:
external image
Source: antwrp.gsfc.nasa.gov...
"The cluster is so massive and so compact that its gravity bends and focuses the light from galaxies that lie behind it. As a result, multiple images of these background galaxies are distorted into long faint arcs - a simple lensing effect analogous to viewing distant street lamps through a glass of wine. The cluster of galaxies Abell 2218 is itself about three billion light-years away in the northern constellation Draco. The power of this massive cluster telescope has recently allowed astronomers to detect a galaxy at redshift 5.58."

The Einstein Cross: 2237+030

Source: www.astr.ua.edu...
"Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible in this image. The central cloverleaf is rather light emitted from a background quasar. The gravitational field of the visible foreground galaxy breaks light from this distant quasar into four distinct images. The quasar must be properly aligned behind the center of a massive galaxy for a mirage like this to be evident. The general effect is known as gravitational lensing, and this specific case is known as the Einstein Cross. Stranger still, the images of the Einstein Cross vary in relative brightness, enhanced occasionally by the additional gravitational microlensing effect of specific stars in the foreground galaxy."
Description: antwrp.gsfc.nasa.gov...

A few articles on this topic:

- Dark Matter Distribution: www.cfht.hawaii.edu...
- Dark Matter Map: www.esa.int...
- Basics of Gravitational Lensing: astro.imperial.ac.uk...
- Galaxy Groups Associated with Gravitational Lenses and H_0 from B1608+656: xxx.lanl.gov... (more can be found by doing a search on xxx.lanl.gov... )