What does this mean?

[StevenA (Steven)]

I have The Sky (free version that I got awhile back with my old scope)) by Celestron, but can not find the meaning of the abbrevition in any of the guides etc, which I will put at the end of this message. I hope some one can illusidate me. It may be simple for you but I need lots of help lol. So with out delay here they are:-
Parallax 33,600 mas. 2976119 pc
(Maybe 'mas' = Micro ArcSeconds )
Magnitudes bt 2.003, vt 2.005

So; what is the meaning of the abbrev.'s of :-
" mas " and " bt " as well as " vt " ????

Thanks for the help. StevenA

[dannat (Daniel)]

steven, i can help with the bt & vt - they are blue & visual magnitudes as measure by an astronomer..maybe tycho brahe

not sure amout mas - maybe an abbrev for absolute parallax - (someone will know)

[Jazza (Jay)]

Hi Steven,
mas stands for milliarcseconds (micro would be uas)
bt is blue magnitude and vt is visual magnitude

Have a read of http://en.wikipedia.org/wiki/UBV_photometric_system
If you want more info on what that means
Regards,
Jay

EDIT: Heh quick writing Daniel!