NGC 3199 (APOD 22 May 2008)

Comments and questions about the APOD on the main view screen.
Post Reply
Axel
Ensign
Posts: 92
Joined: Sat Aug 28, 2004 12:41 pm
Location: Montreal, Quebec

NGC 3199 (APOD 22 May 2008)

Post by Axel » Thu May 22, 2008 2:05 pm

"But measurements have shown the [Wolf-Rayet] star is not really moving directly toward the bright edge." Wouldn't it be reasonable to assume that the star was moving away from the direction in which it had ejected the most material, as a simple consequence of action-reaction?

Sputnick
Science Officer
Posts: 458
Joined: Thu Apr 10, 2008 7:18 pm
AKA: Sputnick
Location: Peterborough, Ontario, Canada

Re: NGC 3199 (APOD 2008 May 22)

Post by Sputnick » Thu May 22, 2008 3:39 pm

Axel wrote:"But measurements have shown the [Wolf-Rayet] star is not really moving directly toward the bright edge." Wouldn't it be reasonable to assume that the star was moving away from the direction in which it had ejected the most material, as a simple consequence of action-reaction?
Flowing winds .. flowing shapes .. I have no idea of the answer to the above question .. however, during a WHMIS session this morning I was reminded that flowing liquids generate static electricity (dangerous if the fluid is explosive .. therefore steel containers must be grounded) - also therefore, supposing fluid dynamics possibly applies to flows of Dark Matter/Dark Energy, that could possibly maybe generate the electricity which Ralph Juergens theorizes shapes this universe, you know the universe we live in, possibly not the other universes because they might have different mechanisms like little wind up springs.
If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.

Arramon
Science Officer
Posts: 210
Joined: Mon Sep 13, 2004 2:52 pm

Post by Arramon » Thu May 22, 2008 10:47 pm

I was just thinking that the shape of the expanding shell looks like its being affected by the IGM as that specific star is on its course around the center of the galaxy. but then I can't tell which way is up, and where the heck is the center of the galaxy in relation to the star in this image causing the shell itself. And where actually is the star in that image causing all this?

User avatar
Case
Commander
Posts: 616
Joined: Sat Jun 09, 2007 10:08 pm
Location: (52°N, 06°E)

Re: Windblown NGC 3199

Post by Case » Thu May 22, 2008 11:49 pm

Arramon wrote:And where actually is the star in that image causing all this?
WR 18 (number 18 in the catalogue of galactic Wolf-Rayet stars) a.k.a. HD 89358 is at the heart of NGC 3199.
Image

User avatar
iamlucky13
Commander
Posts: 515
Joined: Thu May 25, 2006 7:28 pm
Location: Seattle, WA

Post by iamlucky13 » Fri May 23, 2008 12:24 am

This isn't material ejected from the star. It's interstellar material being pushed outward by the radiation pressure and stellar wind. This occurs at the heliopause. In the direction of motion, the build-up is usually greatest, creating a bow shock, but that is not the case here, apparently because the intersteller medium is more sparse in the direction of motion.

Also, material tends to be ejected from stars relatively symmetrically.

Sputnick, flowing liquid or gas only causes an electric charge if the gas itself has a charge, ie, it's carrying an excess of electrons or protons away from the source. One of the major holes in the electric universe theory is that the universe appears to be electrical neutral across large distances. Because the electric-magnetic force is so strong compared to gravity, charge imbalance has a habit of sorting itself out fairly readily. Lightning is the perfect example.
"Any man whose errors take ten years to correct is quite a man." ~J. Robert Oppenheimer (speaking about Albert Einstein)

Axel
Ensign
Posts: 92
Joined: Sat Aug 28, 2004 12:41 pm
Location: Montreal, Quebec

Post by Axel » Fri May 23, 2008 12:32 pm

iamlucky13 wrote:This isn't material ejected from the star. It's interstellar material being pushed outward by the radiation pressure and stellar wind. This occurs at the heliopause. In the direction of motion, the build-up is usually greatest, creating a bow shock, but that is not the case here, apparently because the intersteller medium is more sparse in the direction of motion.

Also, material tends to be ejected from stars relatively symmetrically.
Right, thanks. Since it's extremely unlikely that radiation pressure or stellar wind would be asymmetrical, one assumes it is evenly distributed and that the uneven shape of the formations around the star has another cause.

I can't imagine how radiation pressure could ever be asymmetrical, but a one-time ejection might be; hence my original question.

Post Reply