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Fraser
2005-May-31, 06:30 PM
SUMMARY: The faster a star spins, the more it flattens out, changing from a sphere to something more egg-shaped. Since stars are points of light in the sky, it's difficult to determine their shape, but astronomers are now using gravitational lensing to get a sense of the shape of stars. This depends on the light from a distant star being deflected by the gravity of something closer. In a recent lensing event, where a closer star eclipsed a more distant star, astronomers were able to detect that the background star was slightly elongated. This is impressive considering the distant star was 16,000 light-years away.

View full article (http://www.universetoday.com/am/publish/measuring_shape_stars.html)

What do you think about this story? Post your comments below.

om@umr.edu
2005-May-31, 06:38 PM
This is an interesting new development.

I am a bit uneasy that light from this distant star was first "lensed" and then "un-lensed" to determine the original shape of the star.

Might not the shape of a close-by star be used to confirm this egg-shaped geometry?

With kind regards,

Oliver
http://www.umr.edu/~om

lswinford
2005-May-31, 06:49 PM
What about non-homogenous situations? I wonder if young stars are fully centered about their mass. I wonder if in binary or planetary systems with large planetary masses, such as what is usually discovered up until recently, how the center of gravity affects the center of mass or merely warps the appearance. Wouldn't this essentially be a cosmetic thing? If a star is changing fuels, burning, say, hydrogen still in areas of relative abundance while burning heavier elements where they are concentrated from previous fusion centers, would that cause instability and enlargement/depression along regions above where one fusion fire is hotter? I suspect there is more to shape than speed of spin.

Somehow I still suspect that when lensing is used to observe we still have a distorted image. If I were spear-fishing, seeing a fish of one size and location as its image is bent from the water, image then straight through the air, then bent by the corrective lenses of my glasses, then bent by the astigmatism of my eyes (yeah, and probably distorted in the representation of the gray matter between my ears), I really don't know where the fish is--I just take a stab at it, a sort of mechanical guess my arm makes. The only way I know I've got it right is when there is a fish on my spear when I pull it back (fish are pretty lucky creatures, in my experience).

WW
2005-May-31, 06:51 PM
Hi ya everybody,
I have been working on some pictures, and an animation of a star at work....well the one in the animation is the sun, sorry animation is so small but has to resize so many times before msn accepted in their limited pic' space.......lol
I have also been publishing some pictures of what I believe to be star maps and would be really interested in hearing others opinions in these. To say I created alone would be a lie as I am pyschic so worked and working via this....
Before you discard what I'm saying how about taking a look at some of them....

http://groups.msn.com/WENDYSINNOVATIONS/

I have provided a link for the picture I would like some feedback on but there are others too....description etc in there too.

Enjoy!

God bless you!

WW

WW
2005-May-31, 06:59 PM
Oops........the link isn't to the picture but it won't be hard to find, it has been published twice in there, once with light provided....all copyrighted and rights reserved too, but interesting though;)

om@umr.edu
2005-May-31, 06:59 PM
Originally posted by lswinford@May 31 2005, 06:49 PM
I still suspect that when lensing is used to observe we still have a distorted image. If I were spear-fishing, seeing a fish of one size and location as its image is bent from the water, image then straight through the air, then bent by the corrective lenses of my glasses, then bent by the astigmatism of my eyes . . . etc.
I agree, lswinford.

Could a closer spinning star perhaps be studied, without interference from lensing?

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-31, 07:01 PM
Originally posted by WW@May 31 2005, 06:51 PM
I have provided a link for the picture I would like some feedback on but there are others too....description etc in there too.
Hi Wendy,

Can you please provide a more direct link to your animation of the Sun. The link goes to your main site, and I couldn't see any obvious link to anything astronomy related. I suspect that this is a hoax to get traffic to your site, and will (according to forum rules) need to remove this post in a few hours.

erasium
2005-May-31, 09:06 PM
:unsure: Hi all. I have been following these stories about egg shaped stars and
have to add this bit of admitted silliness: Why do they insist on calling it EGG
shaped? I mean if you look at an egg, its sucking in its center not extending it
as you would see if it were spinning. I see a star that is spinning at a rapid rate
as more approaching the shape of an american football when the spin axis is going the long ways through the ball. An egg is SKINNIER in the center, elongated along the "spin axis" if you will as if a band were constricting outward motion in response to a spin. You could think of the egg spinning on its side with the spin axis
through the thinnest diameter but that would be a case of approaching a dumbell shape, two blobs separating by centripal force so that doesn't work either.
So it seems to me its a misnomer to call it "EGG shaped", eh?
worthy of comments? Don

drjgokhale
2005-Jun-01, 04:21 AM
It is surprising news that stars or planets for that matter can exist in a shape other than the familiar flattened sphere, though one might think of skaters spinning faster when tightly gathered together; still, puzzling, it all. What next, a planet system or galaxy in shape other than spiral disc?

Mild mannered
2005-Jun-01, 09:21 AM
Originally posted by drjgokhale@Jun 1 2005, 04:21 AM
It is surprising news that stars or planets for that matter can exist in a shape other than the familiar flattened sphere, though one might think of skaters spinning faster when tightly gathered together; still, puzzling, it all. What next, a planet system or galaxy in shape other than spiral disc?
Indeed.

And if a spinning star can be changed in shape relative to it's rate of spin what of Black Holes?

Both when a star collapses to form a BH: How does this work when the star is egg or any other non sphere shape?

And does a BH similarly become egg shaped as they spin much faster and get faster as they acrue mass (I believe)

WW
2005-Jun-01, 02:38 PM
Hi!
Sorry about that, I did post again to say about the link not directing you to the pictures. The link will take you to the front of my group....yes, and to your right you'll see a few pictures then click on 'pictures' at the bottom and you'll be directed to them. I understand you thinking I'm trying to pull traffic to my group, but it is actually a closed group (read only) as I accept no membership applications, my reasons explained on the front of my group. I only provided the link as looking for some feedback and to be honest, quite amazed by them myself.
The animation is tiny but I do have a larger animation of it too but msn limited had me resizing to a almost stamp size animation..lol! It is in the front 'whats new' of the group. I not only wanted some feedback if possible (in here) but thought I'd share some really beautiful pictures too.

Thanks, and take care

WW

WW
2005-Jun-01, 02:45 PM
Here's the direct link to the animation: http://groups.msn.com/WENDYSINNOVATIONS/_whatsnew.msnw

You really do need to get close up to the screen or have really good eye sight to see and wait long enough for it to start rotating etc properly to see the beauty in it.
I hope you can see it properly but as said before, I do have a larger animation with all the details shown but I think you'll see it... as I can.

antoniseb
2005-Jun-01, 03:04 PM
Originally posted by WW@Jun 1 2005, 02:45 PM
Here's the direct link to the animation:
Try this link:
Wendy's Animation (http://groups.msn.com/isapi/fetch.dll?action=MyPhotos_GetPubPhoto&PhotoID=nGQAAAHoFlTXMGf80o8Cht1SEsmDUqIMKYr7Jo*Jyp SnmHLzX06KAz0*2weskJ6w9)

Wendy, this is a cool animation, but there is nothing about it that says it shows how the Sun works. I'll leave this posting up, but I hope that in the future you'll participate in this forum on topics more closely connected to astronomy.

BTW, did you make this animation, or did you find it somewhere that we should give credit to.

WW
2005-Jun-01, 05:01 PM
OK.....I'll really really try and discuss topics with relevance to this site, and hey.......thanks for the cool link, yeah I did do myself and was rather annoyed to spend so long creating for it to have to be so small in msn but never mind...lol!
It's a great site you have here and some interesting reads too.

Thanks again

-WW-

Greg
2005-Jun-02, 02:17 PM
Sometimes it would be helpful to do a web search or use the forum search engine to try to answer some of these questions. There was a recent article posted here that addresses this issue.
http://www.universetoday.com/am/publish/eg...ng.html?2112005 (http://www.universetoday.com/am/publish/egg_regulus_spinning.html?2112005)
Hopefully this will help convince you that an oddly shaped star is not a new concept and in fact has been observed before with very precise instrumentation. I would think that any overall distortion affecting a lensed image would affect the whole image and not specificly the speck of a star in that image.
Whenever I want more information on a topic I have a question about, all I do is open a 2nd web browser page, call up my favorite search engine (Google in my case) type in a few key words, and nearly always I get a few relavant articles that help answer my question(s). The whole process takes less than a minute, excluding the time it takes to read whatever articles I get.

LioNiNoiL
2005-Jun-07, 06:05 AM
Originally posted by Sonhouse Don
Why do they insist on calling it EGG
shaped?
It's because the dimwits have never taken a close look at an egg.

antoniseb
2005-Jun-07, 03:12 PM
Originally posted by LioNiNoiL+Jun 7 2005, 06:05 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (LioNiNoiL @ Jun 7 2005, 06:05 AM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-Sonhouse Don
Why do they insist on calling it EGG
shaped?
[/b][/quote]
It&#39;s because the actual word used is ovoid (meaning three dimensional surface created by rotating an oval). This word also means egg-shaped, but that is the wrong meaning for this context, yet journalists insist on using more picturesque terminology.