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#76 2005-01-13 08:04:30

Palomar
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From: USA
Registered: 2002-05-30
Posts: 9,734

Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.spaceref.com/news/viewpr.htm … 5897]Dwarf galaxy has giant surprise

*Reminds me of the previous article in this thread.

Not only may this dwarf galaxy shed light on how galaxies form, but also the correlation between gas -and- stars within.

The galaxy studied is 16 million ly away.  It's enveloped in a humongous hydrogen gas disc...which hasn't  been involved with the galaxy's star-forming processes and may be "primordial material" left from its own formation.

"Why the gas in the disk has remained so undisturbed, without stars forming, is somewhat perplexing. When we figure out how this happened, we'll undoubtedly learn more about how galaxies form," she said.

Discusses observation of objects with visible-light instruments versus radio telescopy:

When she observed the galaxy later using the radio telescope, she found that it is embedded in a huge disk of atomic hydrogen gas. In visible light, the elongated galaxy is about 6,000 by 4,000 light-years, but the hydrogen-gas disk, seen with the VLA, is about 41,000 by 28,000 light-years. "The gas disk is more than seven times bigger than the galaxy we see in visible light," she said.

Haynes was amused that a galaxy that looked "boring" to some in visible-light images showed such a remarkable feature when viewed with a radio telescope.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#77 2005-01-13 13:45:03

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.universetoday.com/am/publish … 5]Globular cluster crammed with microsecond pulsars

*So "busy" they're using the analogy of a "buzzing beehive" to describe it.  There are 13 in binary systems among the pulsars, and two of them rotate at a speed of 600 times per second (which, according to the article, is as fast as a household blender).  Amazing. 

Cluster's name is "Terzan 5" -- it's located "in" Sagittarius and is 28,000 ly away.  Holds the current record of the most pulsars within a globular cluster:  24.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#78 2005-01-14 10:16:05

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

You will love the nebula photo's that are part of this article http://www.space.com/scienceastronomy/p … html]Cause of Strange Cosmic Shapes Pinned Down. Thank's go to Hubble and the other space telescopes used in this research.

*Here's another:

http://www.spaceref.com/news/viewpr.htm … 5905]Water Fountain Nebula

Is very complex to try and describe (understatement -- or maybe my brain's just tired), so I'll opt for copy and paste of most interesting (IMO) details:

The images show two lobes, which are cavities (each of size about 2000 Astronomical Units) in an extended cloud of gas and dust, illuminated by light from a central star which lies between the two lobes, but is hidden from our view behind a dense, dust lane that separates the two lobes. These near-infrared AO images probe much deeper than HST into the two lobes of the Water-Fountain Nebula, showing a remarkable corkscrew-shaped structure (marked by dashed lines) apparently etched into the lobe walls.

According to JPL Research Scientist Dr. Sahai, " The corkscrew structure seen here is the proverbial writing on the wall signature of an underlying high-speed jet of matter which has changed its direction in a regular fashion (called precession). These images of the Water-Fountain Nebula thus show direct evidence for a jet actively carving out a bipolar nebula, providing unambiguous support for our recently proposed hypothesis that the shaping of most planetary nebulae is carried out by such jets".

The discovery of the corskcrew pattern resulting from a precessing jet in the Water-Fountain Nebula is an exciting addition to our knowledge of jets in dying stars as well as astrophysical jets in general. The jets in dying stars are thought to operate for a very short period of time (few hundred years).

Phenomenal.  :up:  Trying to visualize it all.  smile 

Sure is a fun challenge, trying to keep up with all the astronomy news pouring in on a nearly daily basis.  :laugh:  The 11-year-old me couldn't have ever imagined today's never-ending info feast.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#79 2005-01-15 09:44:53

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.space.com/imageoftheday/imag … 4.html]NGC 2467:  Hotbed of starbirth

*Lovely image, new from Gemini South in Chile.  Is 17,000 light years away -- "in" the constellation Puppis. 

Note the star in the lower left-hand corner; a brief comment is made towards the end of the caption.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#80 2005-01-18 11:50:21

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.eurekalert.org/pub_releases/ … hp]Rapidly rotating star dubbed 'King of Spin' by research team

New ultraviolet observations indicate a Milky Way star is spinning nearly 200 times faster than Earth's sun, the probable result of a merger between two sun-like stars whose binary orbit recently collapsed, according to a University of Colorado at Boulder astronomer.

*Just got around to reading this (it's still front-page news at one web site).  It's only 800 light years away, which of course is near enough to be observed in good detail.

"FK Com objects are oddballs because most giant stars rotate very slowly. That's why many theorists now believe binary mergers are the best way to explain the existence of these rare, ultra-fast rotators,"

*I once read an article which stated two stars merging isn't as violent a process as might be expected -- there's no explosion, but rather the stars come together like two drops of water.  :up:  Their outer shells begin stretching out until they touch -- at which point they look like teardrops -- and gradually they pull each other in.  If I can find an illustration of that process, I'll post it; can't recall if an illustration accompanied that other article or not (this was months ago). 

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#81 2005-01-18 15:07:02

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.universetoday.com/am/publish … 812005]The Case of the Missing Dust Disks

*Red dwarf stars account for 70% of the stars in our galaxy, but rarely if ever have dust disks surrounding them.  They think "stellar wind drag" is the culprit.  Red dwarves apparently have very intense magnetic fields which produces a stronger solar wind those of younger and more massive stars (A, F and G types).

Interesting.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#82 2005-01-18 15:41:24

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

*Lots of astronomy news today.  Am about to get off-line, so pardon me if I do less commenting than usual.  This story can't be passed up:

http://www.spaceref.com/news/viewpr.htm … 40]Regulus:  The Bullet Star

*Regulus (and Leo of course) are on the rise around 9:00 p.m. my time.  Have known Regulus has a fast spin, but this article really fleshes out the matter.  Whereas Sol's equatorial speed is approximately 4500 mph, Regulus' is 700,000 mph.  It has a bulge at its equator (a stellar rarity), and also its surface is cooler and dimmer at its equator than at its poles.  :-\  That dimmness factor is called "gravity darkening" and has only been previously detected in -binary- stars.  :-\

Regulus' centrifugal force causes it to expand so that its equatorial diameter is one-third larger than its polar diameter. In fact, if Regulus were rotating about 10 percent faster, its outward centrifugal force would exceed the inward pull of gravity and the star would fly apart

Amazing universe.

Check out illustration comparing Regulus to Sol.  Is also 350 times more luminous than Sol. 

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#83 2005-01-19 07:38:13

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://antwrp.gsfc.nasa.gov/apod/ap050118.html]Blue & Silver

*Gorgeous.  Is a nebula in the Small Magellanic Cloud; 210,000 light years away.  Its diameter is 200 ly.  Active star-forming region.  Blue, and purple/purplish, nebulae are my favorites.

-*-

http://antwrp.gsfc.nasa.gov/apod/ap050116.html]On Again, Off Again?

*This nebula has an interesting history.  Its appearance is striking too; not just because of its red color, but its tattered-curtain appearance.  smile

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#84 2005-01-19 12:40:27

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.space.com/scienceastronomy/h … html]Where to draw the line:  Brown Dwarf or Giant Gas Planet?

*A brown dwarf they're studying (orbits a star 48 ly away, about 50 million years old) is much more massive than anticipated.  It's called AB Dor C (geez...) and it's at least 88 times as massive as Jupiter; that's twice the amount "conventional thinking" would have previously made allowances for. 

Brown dwarfs are many times more massive than Jupiter, but they don't have enough material to force a jumpstarting of thermonuclear fusion, the engine that powers a regular star

140 extra-solar planets have been found, many of which are more massive than Jupiter -- some much more so.  Astronomers are trying to determine the drawing line in distinguishing between brown dwarves and giant gas planets.

Complicating the matter, several objects that appear to be in the acceptable mass range for planets -- up to about 15 Jupiter masses -- were discovered about five years ago floating freely in space, not bound to any star. Astronomers have been arguing ever since whether these objects are planets or brown dwarfs.

Wish I could help solve the mystery... 

"Theory predicts that this low-mass, cool object would be about 50 Jupiter masses," Close said. "But theory is incorrect: This object is between 88-98 Jupiter masses. This discovery will force astronomers to rethink what masses of the smallest objects produced in nature really are."

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#85 2005-01-19 13:55:59

SpaceNut
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

I think the difference would be that at some point more heat is given off than it would recieve from a nieghboring star.

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#86 2005-01-21 10:31:43

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://antwrp.gsfc.nasa.gov/apod/ap030314.html]DEM L71:  When Small Stars Explode

*Looks like a psychedelic raindrop.  cool 

(Okay, so it's a false color x-ray image, but still...)

Large, massive stars end their furious lives in spectacular supernova explosions -- but small, low mass stars may encounter a similar fate. In fact, instead of simply cooling off and quietly fading away, some white dwarf stars in binary star systems are thought to draw enough mass from their companions to become unstable, triggering a nuclear detonation.

They're quite certain it was a white dwarf star.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#87 2005-01-22 04:18:17

GraemeSkinner
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From: Eden Hall, Cumbria
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Website

Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

Ok, these are not new discoveries, but show a good deal of determination to complete

http://epod.usra.edu/archive/images/ana … g]Analemma Image

image caption

Wojtek Rychlik, Pikes Peak Photo -
Earth Science Picture of the Day for January 22, 2005
The analemma above was made from my home in Cascade, Colorado (near Colorado Springs). Because we had approximately 300 mostly sunny days here in 2004, it was possible to portray the Sun's motion during the course of a year -- each image was taken at 14:28:00 (local time). 365 photos were used between December 4, 2003 and December 4, 2004. The image of the Sun for December 5, 2003 nearly perfectly overlaps the image for December 4, 2004. When a day was cloudy, an extrapolation was made.

Graeme


There was a young lady named Bright.
Whose speed was far faster than light;
She set out one day
in a relative way
And returned on the previous night.
--Arthur Buller--

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#88 2005-01-22 10:56:36

Palomar
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From: USA
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

*That's a stunning image, Graeme; the best analemma image I've ever seen.  :up:

Same for me:  Not "new" per se (well...as human history goes, ALL this stuff -is- new, lol), but can't pass these up:

http://antwrp.gsfc.nasa.gov/apod/ap030621.html]Crescent Earth at Midnight

Looks so peaceful and tranquil.  Looks are decei...  But beautiful.

-*-

I am quite sure I've never seen this image before (just when I thought I'd seen 'em all, particularly as concerns past missions):

http://antwrp.gsfc.nasa.gov/apod/ap020225.html]Crescent Europa

My only recollection are face-on pics of Europa, or upclose shots.  It looks unreal, as if someone sliced the photo with a razor.  :-\

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#89 2005-01-24 11:16:42

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://antwrp.gsfc.nasa.gov/apod/ap030314.html]DEM L71:  When Small Stars Explode

*Looks like a psychedelic raindrop.  cool 

(Okay, so it's a false color x-ray image, but still...)

Large, massive stars end their furious lives in spectacular supernova explosions -- but small, low mass stars may encounter a similar fate. In fact, instead of simply cooling off and quietly fading away, some white dwarf stars in binary star systems are thought to draw enough mass from their companions to become unstable, triggering a nuclear detonation.

They're quite certain it was a white dwarf star.

--Cindy

http://antwrp.gsfc.nasa.gov/apod/ap050123.html]NGC 2440:  Cocoon of a New White Dwarf

*Another great image (though in false color) from Astropix.  Am lately seeing quite a few articles about white dwarf stars.  The WD in this nebula is one of the hottest known.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#90 2005-01-26 05:33:18

SpaceNut
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

Been lots in the news Cindy as you have noted lately most of it is about mass, diameter, color, Spectrum analysis and just plain... Where do you draw the line as to what is a planet versus a dwarf star. Noted from other articles that most planetary dust disk are gone from these stars.. ???

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#91 2005-01-26 05:53:51

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

Been lots in the news Cindy as you have noted lately most of it is about mass, diameter, color, Spectrum analysis and just plain... Where do you draw the line as to what is a planet versus a dwarf star.  ???

*Yep, the spectacle of "gas giant planets" purportedly floating around freely out there.  If it -is- orbiting a star, that might not prove much; there are binary star systems all over the place; could be a brown dwarf orbiting another star.  These objects are much larger than the parameters they've set for how big a gas giant planet can be...

And if it is truly floating about freely, either it's a lost/flung-off planet all alone now or it's a brown dwarf (I'd bet on the latter).

Will be interesting to see the scientists continuing to try and figure it out!  yikes  :laugh:

http://www.spaceref.com/news/viewpr.htm … 5]Evidence builds for supernova's role in Solar System creation

*Article deals with a Chinese meteorite ("the Ningqiang carbonaceous chondrite") and the past presence in our Solar System of chlorine-36; (iron-60 and sulfur-36 isotopes also mentioned).  Did a nearby supernova explosion lend a hand in our existence?  Hmmmm.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#92 2005-01-26 06:00:50

SpaceNut
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

I know that we have been searching for exoplanets and have found some to orbit very tightly to there parent stars. Could any of these fit into the drawf star category, say if they where all alone or where flung to a distance away from any of there discovered locations?

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#93 2005-01-27 06:31:20

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

I know that we have been searching for exoplanets and have found some to orbit very tightly to there parent stars. Could any of these fit into the drawf star category, say if they where all alone or where flung to a distance away from any of there discovered locations?

*Well, if it's in a tight orbit with a healthy star -- based on what I've read -- it's probably a planet.  But it could be a binary system of one regular, healthy star and a brown dwarf that didn't quite make it as a regular star.  If it's out drifting about on its own and it's much bigger than the general parameters set for size, mass, etc., of a gas giant -- then it's probably a brown dwarf.  It'll be interesting to watch the scientists try to sort this out (I'm certainly no "authority" on these issues by a long shot...).  (By the way, a previously posted article says 70% of the stars in our galaxy are RED dwarf stars...I'm not sure of the percentage for BROWN dwarves; anyway, perhaps there aren't as many exoplanets out there as is hoped).

-*-

http://www.spaceflightnow.com/news/n0501/26haloes/]Dark matter haloes:  First objects in the universe

This is a cool article.  Am pressed for time, so will paste some highlights.  These "ghostly haloes" of dark matter are as large as our Solar System and as heavy as Earth.  The Milky Way has "quadrillions" of them, with one expected to pass by us every few thousand years...

leaving a bright, detectable trail of gamma rays in its wake, the scientists say. Day to day, countless random dark matter particles rain down upon the Earth and through our bodies undetected.

"These dark matter haloes were the gravitational 'glue' that attracted ordinary matter, eventually enabling stars and galaxies to form," said Prof. Ben Moore of the Institute for Theoretical Physics at the University of Zurich, a co-author on the Nature report. "These structures, the building blocks of all we see today, started forming early, only about 20 million years after the big bang."

Dark matter comprises over 80 percent of the mass of the universe, yet its nature is unknown.

If a dark matter halo were to pass by Earth in our lifetime, it'd give scientists the opportunity to "easily see" a bright trail of gamma rays.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#94 2005-01-27 09:20:10

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.spaceref.com/news/viewpr.htm … 992]Pulsar pair gives scientists magneto-pause for thought

A study of the first double-pulsar binary system to be discovered shows that magnetic interactions between the pulsars are strikingly similar to those between the Sun and the Earth.

*This pulsar pair was discovered in 2003; are the only (yet known) example of both co-orbiting bodies showing the regular flash of a pulsar signal.

A rotates 44 times per second; B rotates 2.8 times per second.  Each is about 10 km across but are surrounded by a magnetosphere thousands of km's in diameter. 

Lots of *good* info in this article.  Another "must-read" for astronomy buffs.   :;):

Observations show that there is a distinct boundary, or magnetopause, surrounding pulsar B's magnetosphere. Just as the solar wind warps the Earth's magnetosphere as it sweeps past, a wind emitted from pulsar A appears to be constricting the magnetosphere of pulsar B, compressing it into a comet-like tail that streams radially outwards.

By contrast, pulsar A's magnetosphere is much smaller and appears to be unaffected by its proximity to pulsar B.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#95 2005-01-30 20:31:13

Palomar
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.astronomy.com/asy/default.as … scillating stars reveal their ages

*Use of stellar seismology.  Study involves Procyon and Eta Bootis.

These vibrations let astronomers probe the star's interior, just as earthquakes let seismologists study Earth's core and mantle.

 

cool

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#96 2005-01-31 11:46:47

Palomar
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Posts: 9,734

Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.spaceflightnow.com/news/n0501/26haloes/]Dark matter haloes:  First objects in the universe

This is a cool article.  Am pressed for time, so will paste some highlights.  These "ghostly haloes" of dark matter are as large as our Solar System and as heavy as Earth.  The Milky Way has "quadrillions" of them, with one expected to pass by us every few thousand years...

leaving a bright, detectable trail of gamma rays in its wake, the scientists say. Day to day, countless random dark matter particles rain down upon the Earth and through our bodies undetected.

"These dark matter haloes were the gravitational 'glue' that attracted ordinary matter, eventually enabling stars and galaxies to form," said Prof. Ben Moore of the Institute for Theoretical Physics at the University of Zurich, a co-author on the Nature report. "These structures, the building blocks of all we see today, started forming early, only about 20 million years after the big bang."

Dark matter comprises over 80 percent of the mass of the universe, yet its nature is unknown.

If a dark matter halo were to pass by Earth in our lifetime, it'd give scientists the opportunity to "easily see" a bright trail of gamma rays.

--Cindy

http://www.spacedaily.com/news/darkmatter-05b.html]In the Stars:  Dark Matter's Creative Hand

*Excellent.  It ties in with the previous article; in fact, some info is repeated but this article has much more. 

Visible matter accounts for less than 5% of the universe's mass.  Dark matter accounts for about 25% and dark energy approximately 70%.  Amazing.

Next to nothing is known about dark energy, except it seems to be strong enough to be accelerating the expansion of the universe, pushing it toward an utterly cold and silent end.

Dark matter is beginning to be another story. Still theoretical - scientists so far have not been able to observe direct evidence of its existence - the possibility of dark matter first emerged because of a puzzling phenomenon.

When astronomers began measuring both the rotation rates and probable masses of galaxies, they were surprised to discover the two figures did not match. The outer stars of galaxies seemed to be orbiting at speeds that should have sent them careening into space. Yet they remained captured by gravitational forces that appeared far too weak to contain them.

Black holes and "dust" were considered as explanatory, but fell short because neither are massive enough to create the necessary gravity. 

Newly-named particle:  Neutralino. 

Neutralinos apparently were ideal candidates for galactic formation. They do not move very fast and clump together easily, enough to create the gravitational wells - the seed pods of future galaxies.

They're speculating that it could be dark matter which disturbs comets in/near the Oort Cloud, propelling them towards the inner Solar System.

A quicker way to detect neutralinos, he said, would be to look at the galactic center, where dark-matter density is highest. The denser regions provide a greater chance of neutralino collisions and therefore more gamma-ray emissions.

Still, Diemand said, "this would still be difficult to detect, like trying to see the light of a single candle placed on Pluto."

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#97 2005-02-01 06:52:54

Palomar
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Registered: 2002-05-30
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Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

*Just a bit of "potpourri":

http://antwrp.gsfc.nasa.gov/apod/ap000428.html]Leonid Glowworm

This is cool because they're "mysteriously self-luminescent" and don't shine via reflected light.  They're battered by high-altitude (100 km) winds and "take on progressively twisted worm-like shapes." 

What makes the Glowworm glow? To find out, SOR astronomers engaged in a unique experiment, tracking and probing both 1998 and 1999 Leonid meteor trains with pulsed laser lidar (light detection and ranging) systems and other instruments.

-*-

http://antwrp.gsfc.nasa.gov/apod/ap0106 … Tremendous explosion across the universe

*A bit dated (few years), but is interesting.  Resulted in an almost yet-unmatched international response; lots of telescopes and equipment involved.  Hubble obtained the image -and- was first to get an accurate distance:  The explosion occurred near "redshift 2" -- which is "most of the way across the visible universe."  yikes  Keck II confirmed Hubble's results.

To date, they still don't know what type of explosion this was.

Unusual features of the light curve are still being studied, and no host galaxy appears near the position of this explosion.

No problem, we're staying tuned.   :;):

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#98 2005-02-01 22:27:07

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

I came across http://www.spacedaily.com/news/outerpla … .html]THIS INTERESTING ARTICLE today.
    It seems that a good case can be made for the possibility that Pluto's moon Charon was formed in the same way as our Luna.

Dr. Robin Canup, assistant director of Southwest Research Institute's (SwRI) Department of Space Studies, argues for such an origin for the Pluto-Charon pair in an article for the January 28 issue of the journal Science. ...
     ... According to Canup, a collision in the early Kuiper Belt - a disk of comet-like objects orbiting in the outer solar system beyond Neptune - could have given rise to a planet and satellite with relative sizes and angular rotation characteristics consistent with those of the Pluto-Charon pair. The colliding objects would have been about 1,600 to 2,000 kilometers in diameter, or each about half the size of the Earth's Moon.

    If this is found to be true, it would mean that the same process occurred twice in one star system, which must enhance the odds that such moon-forming collisions occur commonly in other systems. The fact that small asteroids have been found to have orbiting companions only adds to the strength of this argument.

    Since our Moon can be shown to have helped to create and perpetuate conditions suitable for life here on Earth, perhaps life-bearing planets around other stars are more common than we used to believe.
                                                   ???    smile


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#99 2005-02-02 09:06:23

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://antwrp.gsfc.nasa.gov/apod/ap981123.html]*Want to see a meteor explode?

Found this yesterday.  It's 4.2 Megabytes and downloaded more slowly on my computer than I'd expected.  At the end of the movie a dimmer meteor passes through the field.  Taken 17 November 1998.  Fanned out to 16 times the diameter of a full moon.

-*-

http://antwrp.gsfc.nasa.gov/apod/ap990203.html]Combined power of at least -hundreds- of supernovae fueling this thing...

Amazing image too.  It spans 1000 light years and is but one of many. 

Recent radio observations show new details of hot gas expanding rapidly from an energetic star-forming region in our Galactic disk out into our Galaxy's halo.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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#100 2005-02-03 12:43:45

Palomar
Member
From: USA
Registered: 2002-05-30
Posts: 9,734

Re: New Discoveries *4* - ...Solar System, Deep Space, cont'd

http://www.spaceref.com/news/viewpr.html?pid=16052]V838 Monocerotis:  Light continues to echo...

*...three years after.  I first posted about V838 last year or in 2003, in one of the former "New Discoveries" threads.  Here's the latest update. 

Very beautiful, too.  That's some red supergiant.  :up:

Is approximately 20,000 ly from Earth.  Strange that light can echo as well as sound. 

The echoing of light through space is similar to the echoing of sound through air. As light from the stellar explosion continues to propagate outwards, different parts of the surrounding dust are illuminated, just as a sound echo bounces off of objects near the source, and later, objects further from the source. Eventually, when light from the back side of the nebula begins to arrive, the light echo will give the illusion of contracting, and finally it will disappear.

--Cindy


We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

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