1. What is the apparent V magnitude of the star Altair?
 
         m(V)  =  0.77

2. The distance to Altair is d = 5.15 pc.
   What is the distance modulus to Altair?

         (m - M)  =  5 * log10 (5.15)  -  5

                  =  -1.44

3. What is the absolute V magnitude of Altair?

         (m - M)  =  -1.44

             -M   =  -1.44 - m

              M   =   1.44 + m

                  =   1.44 + 0.77

                  =   2.21


4. How much power does Altair radiate?
   Is it more or less powerful than the Sun?

         power(Altair)         0.4 * ( 0 - 2.21 )
      ------------------  =  10
         power(M=0 star)

                               -0.884
                          =  10


                          =  0.131

        power(Altair)     =  0.131 * power(M=0 star)

                          =  0.131 * 3 x 10^(28) Watts

                          =  3.9 x 10^(27) Watts

     Altair is more powerful than the Sun, which emits only
     3.8 x 10^(26) Watts.  In fact, Altair is roughly 10 times
     more powerful than the Sun.


Bonus! Would Altair be above the horizon in the sky 
       at 10:00 PM tonight (assuming it were clear)?

             No.  It doesn't rise for several more hours.