Vela Supernova Remnant (APOD 06 Mar 2008)

OutOfScale · Post by **OutOfScale** » Thu Mar 06, 2008 1:44 pm

The text says that the light from the supernova explosion arrived here 11,000 years ago. It also says the remnant is 800 light years awy. That seems inconsistent to me. Has the remnant moved over 10,000 light years in the last 11,000 years? What have I misunderstood?

Thanks, Bill

orin stepanek · Post by **orin stepanek** » Thu Mar 06, 2008 2:20 pm

OutOfScale wrote:The text says that the light from the supernova explosion arrived here 11,000 years ago. It also says the remnant is 800 light years awy. That seems inconsistent to me. Has the remnant moved over 10,000 light years in the last 11,000 years? What have I misunderstood?

Thanks, Bill

I believe it means that the star went into nova 11,800 years ago. Taking 800 years to get here means that the light arrived on earth 11,000 years ago.There is no way of estimating exact date of the nova so 11,000 is probably a very good estimate.
Orin

OutOfScale · Post by **OutOfScale** » Thu Mar 06, 2008 2:33 pm

Of Course! Thanks for the reminder. Bill

orin stepanek · Post by **orin stepanek** » Thu Mar 06, 2008 3:31 pm

The Pencil Nebula: a long narrow ray of feeble light. I have trouble finding this. Seems like a lot of rays of light in this nova.
Orin

neufer · Post by **neufer** » Thu Mar 06, 2008 6:06 pm

orin stepanek wrote:The Pencil Nebula: a long narrow ray of feeble light. I have trouble finding this. Seems like a lot of rays of light in this nova.
Orin

The bright yellow star on the left is lambda Velorum.

The Pencil nebula is a small white streak at around the 5 o'clock position
from lambda Velorum just before one runs into the red nebulosity again.

orin stepanek · Post by **orin stepanek** » Thu Mar 06, 2008 6:40 pm

http://apod.nasa.gov/apod/ap080306.html
OK; I see it!

Thanks neufer. What is the straight line of light above the bright blue star?
Orin

neufer · Post by **neufer** » Thu Mar 06, 2008 10:33 pm

orin stepanek wrote:http://apod.nasa.gov/apod/ap080306.html
OK; I see it! Thanks neufer. What is the straight line of light above the bright blue star?

I would think that, like the Pencil Nebula, that is just another piece of the Vela Supernova:
http://violet.pha.jhu.edu/%7Ewpb/hstvela/hstvela.html

OTOH, it might also be generated by a Wolf-Rayet star in Gamma Velorum (or 'Regor'

).
http://antwrp.gsfc.nasa.gov/apod/ap060519.html
http://antwrp.gsfc.nasa.gov/apod/ap080117.html
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http://en.wikipedia.org/wiki/Gamma_Velorum
http://en.wikipedia.org/wiki/Wolf-Rayet_star

<<Wolf-Rayet stars (often referred to as WR stars) are evolved, massive stars (over 20 solar masses), and are losing their mass rapidly by means of a very strong stellar wind, with speeds up to 2000 km/s. While our own sun loses 10−16 of its own mass every year, a Wolf-Rayet star loses 10−5 solar masses a year. These stars are also very hot: their surface temperatures are in the range of 25,000 K to 50,000 K. The best known (and most visible) example of a Wolf-Rayet star is Gamma 2 Velorum (γ² Vel), which is a bright star visible to those located south of 40 degrees northern latitude. One of the members of the star system (Gamma Velorum is actually at least six stars) is a Wolf-Rayet star. Due to the exotic nature of its spectrum (bright emission lines in lieu of dark absorption lines) it is dubbed the "Spectral Gem of Southern Skies".>>
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Which do you think?

Starship Asterisk*

Vela Supernova Remnant (APOD 06 Mar 2008)

Vela Supernova Remnant (APOD 06 Mar 2008)

Re: Vela Supernova Remnant 6 March 2008

Vela SN - Thanks