Quasar and spectroscopy

[pvelez (Pete)]

Has anyone tried to get a spectrum for a quasar?

For my SAO course, I can do a project on the cosmological redshift and Quasar. In short, an image of a quasar is taken, its spectrum analysed and the effects of the expansion of spacetime assessed from the redshift.

I have a an RC8 on an EQ6 which will be up to the task of imaging a few quasars. However, I only have access to a Star Analyser difraction grating ie no spectroscope. I suspect that this won't have the precision necessary to get a meaningful result.

Has anyone else tried this?

The logical answer is - get outside and give it a go. Sadly, the clouds are everywhere at the moment in Sydney and I need to select my project in the next 2 weeks.

Alternatively, does anyone have access to a spectroscope that I could use? Happy to hire or discuss buying.

Pete

[Merlin66 (Ken)]

Maurice Gavin was the first amateur to successfully record the spectrum and red shift of a quasar back in 1998.
He used a Star Analyser grating on his 12" Lx200 to determine the redshift of the 13th magnitude quasar 3C273.
(This is detailed with a illustration of the results in "Astronomical Spectroscopy for Amateurs", p119)

[Terry B]

What you would like to do is outlined here
http://www.astrosurf.com/buil/us/spe6/quasar.htm

[pvelez (Pete)]

Originally Posted by Merlin66

Maurice Gavin was the first amateur to successfully record the spectrum and red shift of a quasar back in 1998.
He used a Star Analyser grating on his 12" Lx200 to determine the redshift of the 13th magnitude quasar 3C273.
(This is detailed with a illustration of the results in "Astronomical Spectroscopy for Amateurs", p119)

Now that is an inspiration! I have ASforA - picked it up just after my SA arrived about 6 months back. So far I've only used it to extract spectra for some bright stars.

Off to study up

Cheers

Pete

[pvelez (Pete)]

Originally Posted by Terry B

What you would like to do is outlined here
http://www.astrosurf.com/buil/us/spe6/quasar.htm

Thanks Terry - that is a useful site.

Pete

[pvelez (Pete)]

OK I'm convinced I can do this now.

Just found this website

http://www.stargazing.net/david/spectroscopy/3C273.html

with some excellent instructions and some useful links too.

Will let you know how I go.

I must confess I am blown away by this - being able to observe a quasar is one thing (never tried that - for 3C 273 at V mag 12.5 it shouldn't be that hard) - but to determine the cosmological redshift from it from suburban Sydney - that would be seriously cool.

Pete

[pvelez (Pete)]

As I type this, I am keeping an eye o the clearing sky outside as I have yet to nab 3C 273.

Assuming I am successful, what next? I need another quasar for y SAO project. I have reviewed everything on the following list:

http://spider.seds.org/spider/Misc/qso.html

but they are skewed to the northern hemisphere or too dim for me - I particularly like the look of 3C 279 but at mag 17.75 it would be a serious push for me.

Does anyone know how to access a list of quasars by constellation that is suitable for the southern hemisphere. I found one list that looked really useful till I realised that there is nothing on it south of -20.

Pete

[Merlin66 (Ken)]

http://www.klima-luft.de/steinicke/KHQ/khq_e.htm

Check this one out.
(Edit: Just noticed the -20 limit - this is probably the list yu looked at!)
What about:
http://adsabs.harvard.edu/abs/1995RMxAA..31..159M
The seventh list of the Calán-Tololo Survey is presented. It contains information for 100 southern quasars with a B magnitude in the range 16 ≤ B < 19.5; only 20 quasars are brighter than B = 18.

[pvelez (Pete)]

I had another review of the first list you suggest - it suits the bill well. If I can get down to mag 14, I should have a few alternatives.

Thanks

Pete

[rally]

Pete,

Sending you a spreadsheet of Quasars from the Large Quasar Astrometric Catalogue

There are 113,000 to choose from in RA order from 0-360, Dec from -85 to +88 with lots of astrometric data.
Its just under 20mb

There should be one suitable for you !

Rally