How can I find a particular type of star?

I need to find the brightest O star in the sky that is not part of a multiple star system, and the brightest K star. I need to know their RA and Dec, spectral types, luminosity classes, common

names, both absolute and apparent magnitudes, effective temperatures, approximate radii in km, and luminosity in solar luminosities. Where can I find such information? Thanks!How can I find a particular type of star?The visually brightest O-star that is not part of a multiple star system is Naos or Zeta Puppis at 2.21. It is single. For the stellar properties and location as you wanted, please see:



http://www.astro.uiuc.edu/~kaler/sow/nao鈥?/a>

http://en.wikipedia.org/wiki/Zeta_Puppis



Next on that list is Han or Zeta Ophiuchi. If not for the interstellar medium that blocks its light, it would have been at +1.5 magnitude, even brighter than Zeta Puppis. It was once a member of a binary. The other star now is dead and travelling in the opposite direction as a pulsar.



http://www.astro.uiuc.edu/~kaler/sow/zet鈥?/a>



The most luminous though is very much contestable and most are members of a multiple star system and are not visible to the naked eye. I cannot think of a single O-star with a luminosity that climbs to more than a million except for AG Carinae. Maybe if I think long enough, I can remember it for you (just e-mail me instead).



The visually brightest single K star is Arcturus:

http://www.astro.uiuc.edu/~kaler/sow/arc鈥?/a>



The most luminous single K-star visible to the naked eye is Omicron-1 Canis Majoris:

http://www.astro.uiuc.edu/~kaler/sow/omi鈥?/a>



For more info, see this list:

http://www.atlasoftheuniverse.com/stars.鈥?/a>



Then check the properties here:

http://www.astro.uiuc.edu/~kaler/sow/sow鈥?/a>



For the location use Wikipedia.How can I find a particular type of star?This list has the most complete information I can find. It's essentially the same data that you will find in Peterson's Field Guide to the Stars and Planets.



http://www.astro.utoronto.ca/~garrison/o鈥?/a>



The absolute and apparent magnitudes are given. I didn't know which one you needed. If you see an A or AB or ABC after the star name, it is a multiple.



Keep in mind, if you are looking for the greatest absolute magnitude, it will depend on how deep your list goes. You would have to cut it off somewhere. Of all the stars, we really don't know which ones are the brightest O or K stars. So I hope you're going with apparent magnitude. This list is in order of apparent magnitude but doesn't tell whether they are multiples or not.

http://www.pa.msu.edu/people/horvatin/As鈥?/a>



BTW, since it looks like you're interested in temperature or color extremes, why not M stars?