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[vsnet-obs 410] NAS.VSS observations of AL Com and U Gem

            Norwegian Astronomical Society - Variable Star Section

     ===== AL COMAE BERENICES - NAS.VSS REPORT NO. 001 (1995 Apr 8) =====

    This SU UMa/WZ Sge type dwarf nova is currently in a very rare outburst
    and the following observations are available by observers of NAS.VSS:
    ----------------------------------------------------------------------
    YYYY MM DD.DDD  LIGHT ESTIMATES     MAG  CL INSTRUM.   OBSERVER
    ----------------------------------------------------------------------
    1995 04 07.860  A-5;B-5            12.4  2  C203,123x  Granslo, B.H.
    1995 04 07.892  B-6;C+7            12.7  2  C203,133x  Dahle, H.
    ----------------------------------------------------------------------
    Comparison stars (identifications from TA Electronic Circular No. 943;
    magnitudes by Stanton and Bertola): A = 11.85, B = 11.96, C = 13.51.
    No observations were made on Apr. 5/6 and 6/7 due to overcast skies.

    According to an email message by J. Mattei, director of AAVSO, this
    eruption was first reported by D. York, Abiquiu, NM, USA on Apr. 5.149
    UT at mag. 14.9, and confirmed by T. Cragg, Coonabarabran, NSW,
    Australia on Apr 5.600 at mag. 12.7. Subsequently, L. Szentasko,
    Veresegyhaz, Hungary reported a very uncertain positive observation
    from Apr. 3.804 at mag. 15.7::. A negative observation by P. Schmeer,
    Bischmisheim, Germany from Apr. 4.97 gave mag. [13.7. This is the
    first outburst observed since March 1975.

    AL Com is located about 10' SE from the well-known spiral galaxy M 88
    (NGC 4501) and N. James, Chelmsford, England has measured the following
    accurate position:
                 h  m   s               o  '   "
         R.A. = 12 32 25.83   Decl. = +14 20 43.0  (equinox J2000.0)
 

        ===== U GEMINORUM - NAS.VSS REPORT NO. 002 (1995 Apr 8) =====

    The following NAS.VSS observations since March 31 have been reported:
    ----------------------------------------------------------------------
    YYYY MM DD.DDD  LIGHT ESTIMATES     MAG  CL INSTRUM.   OBSERVER
    ----------------------------------------------------------------------
    1995 03 31.894  L-7;M-2            14.0  2  M316,270x  Midtskogen, O.
    1995 04 01.860  K-1;M+3            12.8  1  M316,130x  Midtskogen, O.
    1995 04 02.008  H-2;L+8            12.5  2  C203,123x  Granslo, B.H.
    1995 04 02.030  G-5;H-1            12.4  2  C203,123x  Granslo, B.H.
    1995 04 02.817  A-8;B-2;C-1         9.3  1  C203,80x   Dahle, H.
    1995 04 02.888  A-6;B+2             8.9  1  M316,62x   Midtskogen, O.
    1995 04 02.920  A-5;B=V;D+3         9.0  1  C203,123x  Granslo, B.H.
    1995 04 02.923  B=V;C+3             9.0  1  C203,123x  Bjerved, T.V.
    1995 04 03.847  B-1;C+3             9.1  1  M316,62x   Midtskogen, O.
    1995 04 03.919  A-5;B=V;C+2         9.0  1  C203,123x  Granslo, B.H.
    1995 04 03.920  A-6;B=V;C+2         9.1  1  C203,80x   Dahle, H.
    1995 04 04.826  A-6;B+1;D+3         9.0  1  C203,123x  Granslo, B.H.
    1995 04 04.856  B-2;D+2             9.2  1  C203,62x   Midtskogen, O.
    1995 04 07.815  A-6;B-1;C+1;X+2     9.2  1  C203,123x  Granslo, B.H.
    1995 04 07.894  B-2;C=V             9.3  1  C203,133x  Dahle, H.
    ---------------------------------------------------------------------
    Comparison stars (identifications from NAS.VSS (star X) and Burnham's
    Celestial Handbook (other stars); magnitudes by AAVSO): A = 8.5;
    B = 9.0; C = 9.3; X = 9.5; G = 11.9; H = 12.3; K = 12.6; L = 13.3;
    M = 13.8.

    General comments:
    All observations are visual. Time system is year (YYYY), number of
    month (MM) and date with desimals in Universal Time (DD.DDD). Magni-
    tudes are calculated from Pogson's step method (assuming 1 grade
    unit = 0.1 magnitude), i.e. the observation B-1;C+3 means that the
    variable is 0.1 mag. fainter than comparison star B and 0.3 mag.
    brighter than C. CL = class: estimated accuracy of observation: 1 =
    good (+/- 0.1 mag.); 2 = fair (+/- 0.2 mag.); 3 = poor (+/- 0.3 mag.
    or worse). Instrument (type, aperture in millimeters, and magni-
    fication): C = catadioptic telescope (SCT); M = Newtonian reflector.

    Observers: T. V. Bjerved (Fjellhamar, Norway); H. Dahle (Oslo, Norway);
    B. H. Granslo (Fjellhamar, Norway); O. Midtskogen (Tranby, Norway).

                                            Yours sincerely,
                                            Bjorn H. Granslo
                                           Director, NAS.VSS