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Posted: Wed Aug 22, 2007 7:00 pm
by Charlie P.
One of the two saddest artifacts in my office was given to me by an engineer who had tested the repair of damaged tiles - in 1982, on Columbia. They proved that it could be done and back then the hope was that there would be a shuttle-built space station, to which the shuttle would ascend during every flight, for check-out before landing.

It's what's forgotten that will get us every time.

- CRP

PS: The other is the shock-cocooned birthday charm (see "American Vesuvius"). To see it is heartbreak; and I still look to the day when I will find the family, and return the artifact that someone was wearing during that fatal 1/200th of a second.

Posted: Fri Aug 24, 2007 7:59 am
by tollbaby
Now here's a sensationalist headline if I ever saw one...

"GAPING HOLE FOUND IN UNIVERSE"

Posted: Fri Aug 24, 2007 10:58 am
by voralfred
The good news about this hole is, it's not going to swallow us!
Contrary to a black hole, this is an "empty" hole. It appears to be empty of everything, even of dark matter. Thus, it does not attract neighbouring matter. Any matter just at its boundary will be attracted away from it, to regions where there is other matter, not into it. So it'll keep growing.
Still, how it already got that big (and how it got there in the first place) seems to be a mystery. Hopefully, we'll learn a lot about the structure of the Universe by this astounding discovery.

Posted: Fri Aug 24, 2007 11:12 am
by Mr. Titanic
Isn't that strange? Hmm. Lets consider those points. This gaping hole does not attract matter, but instead repels it. In fact, this region has no gravity. The Big Bang also gave birth to our universe by expanding away from an origin. It leads me to suspect perhaps this is where the universe began, and matter was created around but not in it? A bit far fetched I'll agree. But it's still interesting to consider.

Or maybe that is a new universe replacing our own. :shock: (Nah... not likely.)

Posted: Fri Aug 24, 2007 11:43 am
by voralfred
Mr. Titanic wrote: The Big Bang also gave birth to our universe by expanding away from an origin. It leads me to suspect perhaps this is where the universe began, and matter was created around but not in it?
Well, this hole is part of the Big Bang, not outside it. It it just a region where there was less matter than in the surrounding (and, by being less attractive than the surrounding regions, lost to them whatever matter was there to begin with). It is just going against the standard paradigm, which is that the bigger the scale, the less the inhomogeneity. Of course the Big Bang was not perfectly homogeneous, as "small" scale inhomogeneities became galaxies (big constrast), a bit larger became galaxy clusters (less contrast), even larger superclusters (even less contrast). What is surprising is such a big contrast (down to zero density) on such a huge scale. It should tell us something about what kind of inhomogeneities the Big Bang really had, in the beginning. It is surprising, but not to the point of questioning the notion of Big Bang itself. Just the paradigm of "the bigger the scale, the less the inhomogeneity". This is bad enough.... but all the more interesting!

Posted: Fri Aug 24, 2007 11:47 am
by Darb
Mr. Titanic wrote:Isn't that strange? Hmm. Lets consider those points. This gaping hole does not attract matter, but instead repels it. In fact, this region has no gravity. The Big Bang also gave birth to our universe by expanding away from an origin. It leads me to suspect perhaps this is where the universe began, and matter was created around but not in it? A bit far fetched I'll agree. But it's still interesting to consider.

Or maybe that is a new universe replacing our own. :shock: (Nah... not likely.)
If I had to cautiously speculate, I'd say it *might* be something like the space-time analog of the orifice of a Klein bottle, possibly manifesting through higher dimensions. Astrophysicists and Scifi writers alike have been speculating about such things, and this will no doubt get them buzzing like bees.

Very neat.

Posted: Fri Aug 24, 2007 12:41 pm
by Mr. Titanic
Oh. Thanks for clarifying that then. Fact can be stranger than fiction in this case, eh? If not nearly identical. Astounding just isn't enough of a word to describe it!

Posted: Fri Aug 24, 2007 1:08 pm
by Darb
I have no idea if I'm right ... this is just idle armchair speculation based on that one linked article. At the very least, i'm sure this possible first evidence of such (if that's what it turns out to be) would be a truly gobsmacking event for a lot of theorists out there.

Posted: Fri Aug 31, 2007 4:48 pm
by Charlie P.
The void is a tad bigger than others, and it's a little surprising - but not consistent with uniquely localized repulsive forces. "Dark energy" (which may close the universe in a 2nd oscillating Big Bang preceded by a cosmic crunch) is equally accelerating the cosmic expansion everywhere. Think of voids somewhat as bread expanding with yeast bubbles everywhere (even beyond our visible 13.7 billion light-year radius), except that this bread provides no opportunity for a grandstand view because (even beyond the visible radius), its center is everywhere and its edge is nowhere. You're always within it. (Circularly, possibly.) As Ed Bishop has said, "Who needs hallucinogens when you've got particle physics?" Reality is far more interesting. - CRP

Void

Posted: Mon Sep 10, 2007 8:50 pm
by JW Nugent
Using a simplified view - the voids can be like voids created when WTC collapsed or like void spaces created in any chaotic turbulance. Universal turbulance might resemble that of a boiling pot of water. The more we complicate ideas the more they become unreachable. Going back to the original work of various scientists and mathematicians gives a very different view of a subject than often found in the classroom.

For me the universe is infinite. what we call the big bang was a localized occurance a small pop in an infinitely larger body. Using this logic the universe is large beyond our limited view and small could be small beyond our ability to imagine how small the matter of the universe can be. Under subatomic we can find sub quantum what sub strata (more likely stratas) exist we cannot yet imagine.

When viewing the WTC collapse the bloom of dust resembles the bloom of clouds which in turn resembles a upward plume of smoke (whether from a cigar or a house onfire. This same turbulance appears in the movement of all matter given the right conditions. If we could replicate the flow patterns of air in a room we would unlock the mystery of water and increase our undestanding so much more. When we can model the charactoristics of a cloud to the smallest detail we will have unlocked all of science; at least until the next plateau.

While there are many suprises waiting us as we evolve no matter how complex our science becomes there will be a similarity to the movement of air or water. Chaos is never random; there is always a larger pattern or design that chaos adheres to. A molecule of water in a flowing stream may be traveling in any direction, but the movement of all molecules resulte in what we see as a flowing stream. Chaos within a pattern; variable but similar to any stream flowing in the same way or any moment of flow past a single point.

The trick is to find a way to tie all these similarities together. There will always be suprises but similarity or universitality will rule.

Posted: Tue Oct 02, 2007 10:30 am
by Darb
Here's a website with some pretty spectacular photos of/from the Space Shuttle ...

http://www.texasjim.com/NASApix/NASA%20pix.htm

Latest Endeavor Mission Photos

Posted: Sun Oct 28, 2007 11:34 pm
by Charlie P.
Dear Brad: These were well worth a look. Even going around nowhere fast in low-Earth orbit, the views are spectacular. - - Charlie P.

Posted: Thu Nov 08, 2007 12:38 pm
by Darb
Last night, quite by accident, while flipping channels at around 1:30 am, I caught the first ever live downlink from the space station in HIGH DEFINITION. It turns out it was just a partial preview for a fuller broadcase on Nov 15th.

http://www.spaceref.com/news/viewpr.html?pid=21273

The images looking down at the Earth from space were incredible ... like the images linked in the post above, only in full motion real time TV.

Posted: Thu Nov 08, 2007 12:58 pm
by Darb
Extra planet(s) discovered around 55 Cancri ...

http://www.nytimes.com/2007/11/06/scien ... etweb.html

Posted: Thu Nov 22, 2007 8:49 am
by tollbaby
Eight "white dwarf" stars discovered in the Milky Way...

http://news.yahoo.com/s/nm/20071121/sc_ ... szO0oE1vAI

Posted: Thu Nov 22, 2007 9:07 pm
by Mr. Titanic
Oh wow, that is really interesting. Usually, when a star enters its later phases in life, it begins to burn heavier elements than the two lightest and most typical - Hydrogen and Helium, hence why larger atoms such as the Oxygen and Carbon described are usually present at the core by that time. I don't quite understand how an atmosphere can contain carbon though. Oxygen, Helium and Hydrogen are all gases, but Carbon is a solid. Perhaps it is a form of ash, such as the condensation nuclei on earth that are thrown into the atmosphere following volcanic eruptions? Individual atoms I suppose, but it still makes little sense. One would think those atoms would fall back down to the stars surface, unless convection plays a role as well.

Theories. Theories. Theories.

It's funny you mentioned that Tollbaby. Just last night (well, this morning) my friend and I were discussing this video. I nearly forgot to breathe watching it pan out like that. The vastness of the universe compels and frightens me. It feels like you're about to choke thinking about such endless matter...

Posted: Thu Nov 22, 2007 9:28 pm
by Darb
Mr.T: Re ... Carbon.

I think most, if not all, elements can exist in a plasma like state, if sufficiently heated and compressed.

Posted: Thu Nov 22, 2007 10:48 pm
by Mr. Titanic
That's a good point, Brad. I suppose like liquid Nitrogen. Hmm. I'll have to ask my Chemistry professor about that.

Posted: Thu Nov 22, 2007 11:42 pm
by voralfred
The point is not that the carbon is in a plasma state: these stars are described as "white", thus white-hot, hotter than our sun which is yellowish. Of course carbon is in a plasma state of individual atoms at this temperature.
What surprises astronomers, if I understood the article correctly, is the following: when all the core hydrogen has been burned to helium, there are two normally possible outcomes for a star:
- heavy stars undergo helium-burning to carbon and oxygen, then go on to burn these elements to heavier ones, then collapse and explode back to supernova, leaving only a very small core (neutron star or black hole)
- lighter stars burn the core to carbon and oxygen and stop. Part of the outlying atmosphere is expelled but part of it is not, and what is seen is a sufficiently thick layer of either hydrogen or helium totally hiding (one does not need much! a small percentage of the total mass will be enough to be totally opaque!) the core of carbon and oxygen, very hot (plasma state) since the core temperature is still higher than the surface: the enormous amount of heat that had been created while the core was still undergoing nuclear reactions has not yet had time to be conducted/convected to the outside, and will keep the outside hot for billions of years; then the star will finally cool and not be a "white dwarf" anymore!
But here one sees the carbon-rich core, for some reason that one does not yet understand, and that is different from these two processes: an event, not as dramatic as a supernova, but more violent than the usual expulsion of just the outermost layers that is expected in the formation of most white dwarfs, has occured: the entire hydrogen or helium outer layer has been expelled, leaving just the central (very hot, in plasma form) carbon/oxygen core that is expected to exist within all white stars. So the surprise is not the existence of the core, but the absence of the outer layers, which allows this core to be seen. This goes agaisnt "traditional wisdom" that some part of these layers normally remain, only part of them are expelled. Even a small amont is sufficient to be opaque. Here the entire outer part has been expelled, all the way to the carbon/oxygen rich core, and what is not understood is this "intermedate" situation, more violent than normal white-dwarf behaviour but much less than the supernova explosion.
It is surprising, but we do not understand all the fine details of star evolution. It is a challenge to find the appropriate model to explain just how it happened.
But the existence of the (very hot, plasma) core of carbon/oxygen is not a paradox in itself. Just the fact that it is seen. In a sense, it even confirms what was usually believed: such a core does exist in the inside of white dwarfs, as theories had predicted!

Among the many references of the White Dwarf article in Wikipedia I found this one rather illuminating.
http://www.shef.ac.uk/physics/people/vd ... wmass.html
The outer part is lost in the "planetary nebula" stage. This reference does say this stage "is not well understood". The amount of hydrogen and/or helium that is not expelled at this stage is not such an essential tenet of the theories. Though the newfound stars are surprising in the fact that hydrogen/helium expulson is total rather than partial, it does not seem to be a paradigm-shattering discovery. A suprise, yes, showing need to refine the models, by all means, but not a dramatic destruction of all that was previously believed to be true.

Posted: Wed Nov 28, 2007 2:00 pm
by Darb
WICKED WITCH OF THE WEST: "Help me, I'm melting !"

WHITE DWARF: {during strata-nova*} "Help me, I'm molting* !"

--------
* Credit to me for the Neologism, credit to Ye Roving Punster for the bad astrophysical pun.

Posted: Fri Dec 07, 2007 12:37 pm
by tollbaby

Posted: Fri Dec 07, 2007 1:00 pm
by Darb
Don't let ufojoe see that leftmost picture, or we'll never hear the end of it. :P

Posted: Fri Dec 07, 2007 4:05 pm
by Mr. Titanic
Oh dear... :lol: :lol: :P

Brad. That was almost as bad as the Astronomy pun. :lol:

Posted: Fri Dec 07, 2007 4:37 pm
by Darb
Coincidentally, I've been watching reruns lately of the 1970 TV series "UFO", in high definition.

http://www.imdb.com/title/tt0063962/

And of course the chief hottie on the show must be mentioned for posterity ... :lol:

http://www.moviemarket.co.uk/Photos/P200550_C56669.html

Posted: Tue Dec 11, 2007 7:12 am
by tollbaby
Don't miss the Geminid meteor shower :) Peaking on Dec 13-14.

http://news.yahoo.com/s/space/20071207/ ... peaksdec13