COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                    NUMBER 460


                    
                             Konkoly Observatory
                             Budapest
                             1970 August 27



      UBV OBSERVATIONS OF NOVA SERPENTIS 1970


    Finding charts for Nova Serpentis 1970 have been given by Burk
head and Seeds (1970) and in the May, 1970 issue of Sky and Telescope,
page 334. The UBV photoelectric observations reported herein were obtained 
on seven nights in May, 1970 at the' No. 2 36-inch telescope of
Kitt Peak National Observatory. Standard observational and reduction
procedures were used (Landolt 1967). The observations were thoroughly
tied into the UBV system each night via observations of some 16 UBV
standards taken from the list of Johnson and Harris (1954). The external
probable errors averaged +- 0. 013 for _V, +- 0.007 for (B-V), and +- 0 .012
for (U-B), as determined from the UBV standard stars May 9th U.T.
was a poor photometric night as indicated by the colons in Table 1.




                Table 1.

   J.D.hel        V       B-V    U-B

2440700.+


 14.9037        11.00    +1.01  -0.46
 15.6450        11.09    +0.92: -0.47
 16.9201        11.13    +0.99  -0.55
 17.9576        11.27    +1.01  -0.56
 18.9635        11.31    +1.01  -0.55
 19.9494        11.37    +0.96  -0.49
 20.9275        11.42    +0.98  -0.49



The heliocentric times of observation are given in column one. As the
data indicates, 85 days after its outburst, the nova has declined 6.6
magnitudes from its maximum of V = 4.4 (Sky and Telescope, page 224,
April, 1970), i.e. at a rate of 0.08 mag. per day. At the time the present 
observations we re made, the nova was continuing to decline in
brightness at nearly the same rate, a rate which is approximately twice
as rapid as that for the recurrent nova T Pyxidis (Landolt 1970). The
color indices remained effectively constant, although they are perhaps
a few tenths of a magnitude more red than is usual for novae (Mumford
1967). This may be explained by the fact that the nova is near obscuring
material as shown on the Palomar Sky Survey Prints.

               
     This work was supported in part by the Louisiana State University 
Graduate Research Council and in part by the National Science
Foundation.



                  References

1. Burkhead, M.S., and Seeds, M.A. 1970, Astrophys. J. Letters, 160,
   L51. [BIBCODE 1970ApJ...160L..51B ]
2. Johnson, H.L., and Harris, D.L., III 1954, Astrophys. J.120, 196. [BIBCODE 1954ApJ...120..196J ]
3. Landolt, A.U. 1967, Astron. J. 72, 1012. [BIBCODE 1967AJ.....72.1012L ]
4. Landolt, A.U. 1970. Publ. Astr. Soc. Pacific 82, 86. [BIBCODE 1970PASP...82...86L ]
5. Mumford, G.S. 1967, Publ. Astr. Soc. Pacific 79, 283. [BIBCODE 1967PASP...79..283M ]


                         ARLO U. LANDOLT
                    Louisiana State University Observatory
                        Baton Rouge, Luisiana



         Corrections to Inf. Bull. No. 443 (TW Her)

Elements (III) and (1V) in Table 3 should be read:

Min = 2433 310.238    +   2d 8068742. E ; E = 7020 (III)
           +- .0026       +-.0000043
Min = 2438 539.4457   +   2d 8068352. E ; E = 8750 (IV)
           +- .0018       +- 0000040