THE ASTRONOMER Electronic Circular No.4 1987 Jan 30 19.54UT

Possible Nova in Hercules
Observations have been reported as follows:
1987 Jan 30.15UT, 7.6 (P.Schmeer, West Germany);30.26, 7.6(G.Hurst)
The sequence on E-circular 3 needs amendment in respect of star G,
the revised value for which is 9.3 based on checks this morning.

Comet Terasako (1987d)
The following orbital elements are
now available:
T=1986 Dec 25.059ET   Peri= 193.95
                      Node=  96.43
q=0.3785 AU           Incl=  41.01
Ephemeris:
1987ET  RA (1950) DEC     Earth Sun   Elong m1
Jan 30 23 55.65 -27 11.66 1.371 0.961 44.0  8.0
Feb  4 00 25.64 -24 02.54 1.442 1.056 46.6  8.5
     9 00 51.43 -20 54.82 1.526 1.150 48.4  9.0
    14 01 13.78 -17 55.62 1.619 1.242 49.5  9.4
    19 01 33.35 -15 08.50 1.721 1.332 50.0  9.9
    24 01 50.70 -12 34.77 1.827 1.420 50.0 10.3
Calculations of the prediscovery ephemeris shows that the comet may
have reached mag 4 around Dec22 when the solar elongation was less
than 1deg.

Comet Nishikawa-Takamizawa-Tago(1987c)
The following observations are
available:
Jan 26.75UT, 8.2(15.6cm spec, Bouma, Netherlands)
Jan 28.75UT, 8.5(Bouma)
Jan 28.80UT, 8.4(15x80B Hurst, Basingstoke);
Jan 29.75UT, 8.5(20.3cm S-C, Schmeer, W.Germany);
Jan 30.79UT, 8.1(Hurst)
Analysis of the ephemeris shows that this comet will not be visible
beyond the dates in E-circular 1 as the solar elongation will be
very small.
David Moore, Eire, has E-mailed a note that this comet was well
placed for discovery well before it was found.
Ephemeris for possible pre-discovery
images:
1986ET  RA (1950) DEC     Earth  Sun  Elong m1
Dec  5 08 04.85 +32 07.45 0.745 1.598 134.7 8.3
    10 07 17.32 +36 11.39 0.615 1.542 148.7 7.8
    15 05 59.82 +39 34.54 0.519 1.487 162.3 7.3
    20 04 15.25 +38 40.68 0.480 1.434 154.6 6.9
    25 02 39.71 +32 08.71 0.509 1.382 132.5 6.9
    30 01 36.12 +24 08.72 0.593 1.332 112.5 7.1
Please send in photographs with dates and exposure start/finish
times quoted.
The magnitudes are uncertain as the comet may have flared at
discovery.
ns are
available:
Jan 26.75UT, 8.2(15.6cm spec, Bouma,