APOD: Wolf-Rayet Star 124: Stellar Wind... (2014 Jul 01)

[APOD Robot]

Wolf-Rayet Star 124: Stellar Wind Machine

Explanation: Some stars explode in slow motion. Rare, massive Wolf-Rayet stars are so tumultuous and hot that they slowly disintegrating right before our telescopes. Glowing gas globs each typically over 30 times more massive than the Earth are being expelled by violent stellar winds. Wolf-Rayet star WR 124, visible near the above image center spanning six light years across, is thus creating the surrounding nebula known as M1-67. Details of why this star has been slowly blowing itself apart over the past 20,000 years remains a topic of research. WR 124 lies 15,000 light-years away towards the constellation of Sagitta. The fate of any given Wolf-Rayet star likely depends on how massive it is, but many are thought to end their lives with spectacular explosions such as supernovas or gamma-ray bursts.

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[Nitpicker]

Wolf-Rayet star WR 124, visible near the above image center spanning six light years across, is thus creating the surrounding nebula known as M1-67.

Is the star WR 124 six light years across, or the image? If the former, that really is a big star!

[Indigo_Sunrise]

Is the star WR 124 six light years across, or the image?

That is my question, too. One link in the description, this one., states "WR 124 is ten times the radius of the sun", which sounds more likely, IMO.

Interesting image, and though I haven't clicked through all the links yet, the ones I have clicked have been informative.

And great job with the processing, Geck!

[Joules]

Nebula, the image, is 6 light years across. A star 6 light years across would be massive enough to already be a black hole, which would make it much smaller and harder to see.
The gas consists of the remains of thousands of coronal mass ejections like these from the sun: http://www.youtube.com/watch?v=cesDB7eoHiE
only much bigger.
CME's are what produce all the small arcs in the nebula structure.

[CURRAHEE CHRIS]

AWESOME!!! \M/ \M/

[geckzilla]

Is the star WR 124 six light years across, or the image?

That is my question, too. One link in the description, this one., states "WR 124 is ten times the radius of the sun", which sounds more likely, IMO.

WR124 Is just the star. M1-67 is the wind nebula or ejecta shell (I've seen it called both) surrounding the star. The star is one of those huge ones, so "ten times the radius of the sun" refers to just the star itself, which is still less than a pixel in the image. This object is about 15,000 lightyears away and is around 1.65' across at the widest point so yeah, 6-7 lightyears across is how big the nebula is.

[Psnarf]

Bet I can: for ((i=0, i<10; i++)) ; do echo "Glowing gas globs"; done. Speaking of glowing gas globs, when the glowing gas globs get far enough away from the star so they no longer glow, thus joining the interstellar medium, that sort of diffuse stellar ejecta is insufficient to account for dark matter?

[Ron-Astro Pharmacist]

Can you say Aurora Monstrificus? Imagine being on a planet orbiting this type of star. Nice place to think of but I wouldn't want to live there. The possibilities for a graphic artist are limitless when given such great ammunition. Perfect lead up into the fireworks for this time of year in the US.

[Chris Peterson]

Speaking of glowing gas globs, when the glowing gas globs get far enough away from the star so they no longer glow, thus joining the interstellar medium, that sort of diffuse stellar ejecta is insufficient to account for dark matter?

Unless it reached absolute zero, it would always glow. And we have the instruments to detect that glow. Dark matter can't be ordinary baryonic matter.

[Chris Peterson]

Is the star WR 124 six light years across, or the image? If the former, that really is a big star!

The largest possible star in terms of size would have a diameter of perhaps a couple hundred light minutes, maybe 20 AU. That wouldn't be the most massive of stars, which are smaller and denser, and probably around 200 solar masses.

[hlwelborn]

A fantastic image! Well done.

[starsurfer]

The Judy Schmidt Delivery Service TM has delivered the goods once yet again!
I think a much more appropriate catalogue designation for the nebula is Sh2-80 as the Minkowski catalogue is for planetary nebulae as this was once mistaken for a planetary nebula. Interesting how many nebulae have been misclassified as planetary nebulae.
Also its quite cool that the constellation of Sagitta contains a second Wolf Rayet nebula around WR 128. One of the few images is this one by the amateur astrophotographer Lionel Mulato.
Also prediction for the future: tomorrow's APOD will be NGC 4651!!!

[geckzilla]

Heh, just the other day I realized I had Gomez's Hamburger misclassified as a planetary nebula. I think it has been a known protoplanetary disk for a while now but somehow I managed to read the wrong things. Part of the problem is how easy it is to mix up a word like "protoplanetary nebula" with "protoplanetary disk". Using "preplanetary" helps but I still wish the effort would be put forth to rename planetary nebulas all together. And change the spelling of Uranus back to Ouranos while we're at it.

[Boomer12k]

Spectacular!!!!!
And with the 4th of July coming up for Americans, appropriate. "Ooooo, aaahhhhh, oooohhhhhh!"......

Simply awesome are the forces at work.

:---[===] *

[Ron-Astro Pharmacist]

Makes one wonder how large stars form in the first place. Searching the topic turned this up.

http://physicsworld.com/cws/article/new ... stars-form

Computer simulations can come up with some wild theories. Bubbles popping out with radiation in the middle. Sounds like someone had a bad simulation day.

[Nitpicker]

Wolf-Rayet star WR 124, visible near the above image center spanning six light years across, is thus creating the surrounding nebula known as M1-67.

Is the star WR 124 six light years across, or the image? If the former, that really is a big star!

Thanks to those who informed me of the size of the biggest known star. As soon as I read the APOD caption, intuition led me to conclude that the "six light years" was not in reference to the star, but the image/nebula. But the caption certainly reads poorly. I should have been more clear in my criticism. It is probably fair to say that a measurable portion of APOD readers will take from this APOD, that WR 124 is six light years in diameter.

[geckzilla]

If the Wikipedia article has a more accurate distance estimate, then the nebula is actually around 5 ly wide. Either way, it's around twice as big as Jupiter ever gets in the sky.

[Nitpicker]

The Wikipedia article says the nebula is nearly 6 light years across. Although the angular size of a nebula must sometimes be a little "nebulous", as it probably depends on the depth of image exposure. And of course the distance measurement has uncertainty. Tis all a bit rubbery.

[geckzilla]

Heh, yeah, and if you do a deeper exposure then the apparent size of the nebula increases! Unless it's young enough that the edges are still sharp and haven't had time to taper off.