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[vsnet-obs 20469] NAS.VSS Report No. 1 of SN 1999by

Norwegian Astronomical Society - Variable Star Section

          SUPERNOVA 1999by IN NGC 2841 - NAS.VSS REPORT NO. 1
          ===================================================

                     [Last update: 1999 May 06]

Supernova 1999by: R.A. = 09h21m52s.1, Decl. = +51o00'07"  (J2000.0)
   [Type Ia]   (Offset from nucleus of parent galaxy: 96" W, 86" N)
                                        (Ref. IAUC 7156, IAUC 7158)

*** OBSERVATIONS ***
----------------------------------------------------------------------
YYYY MM DD.DDD   OBSERVATIONS    MAG   CL  INSTRUM.    OBSERVER
----------------------------------------------------------------------
1999 05 03.958     a-1;b+4      14.3   2   M316;173x   Midtskogen, O.
1999 05 03.981 (ref. USNO-A2.0) 14.5C      M610+CCD    Trondal, O.
1999 05 04.005       G>V       [13.8   2   C203;287x   Granslo, B. H.
1999 05 04.956   F-6;G-3;a=V    14.1   2   C203;287x   Granslo, B. H.
1999 05 05.974     F-2;G+1      13.7   2   C203;287x   Granslo, B. H.
----------------------------------------------------------------------

Time system is year, number of month and date with decimals in U.T.
Observations are visual (step estimates) and unfiltered CCD. Visual
magnitudes are derived by using the sequence below. CL = class:
estimated accuracy of observation; 1 = good (+/- 0.1 mag.), 2 = fair
(+/- 0.2 mag.), 3 = poor (+/- 0.3 mag. or more). Instrument (type,
aperture in mm and magnification): C = catadioptric telescope,
M = reflector.

*** OBSERVERS ***
----------------------------------------------------------------------
Name                Address (instrument)
----------------------------------------------------------------------
Bjorn H. Granslo    Fjellhamar, Norway (20.3-cm f/10 SCT)
Ornulf Midtskogen   Tranby, Norway (31.6-cm f/4.9 newtonian reflector)
Odd Trondal         Groruddalen Optical Observatory, Oslo, Norway
                    (61-cm cassegrain reflector + ST-4 CCD camera)
----------------------------------------------------------------------

*** COMPARISON STARS ***
-----------------------------------------------------------------------
Id     Star Name     R.A. (2000.0) Decl.  V-mag   B-V   R-mag  Ref  Id
TA                   h  m   s    o  '  "                            Sk
-----------------------------------------------------------------------
 3     HIP 45965    09 22 28.5 +51 00 52   8.48  +1.29   7.81  C&F   1
 E     HIP 45922    09 21 50.8 +51 00 36  11.07  +0.59  10.74  C&F   2
 Z   GSC 3431-1249  09 22 53.3 +51 01 28  12.62  +0.64  12.25: Ts   3Ts
 F   GSC 3431-0053  09 21 47.3 +50 58 50  13.51  +0.75  13.08  C&F   3
 G   GSC 3431-0495  09 21 58.2 +51 00 16  13.77  +0.60  13.37  C&F   4
 a   GSC 3431-0159  09 22 02.3 +51 01 23  14.19  +0.83  13.77  C&F   5
 b   GSC 3431-0802  09 22 06.8 +50 53 37  14.72  +0.88  14.23: C&F  147
-----------------------------------------------------------------------

Identifications are from G. M. Hurst, The Astronomer (TA E-Circular
1405, first column), and a sequence compiled by B. A. Skiff
([vsnet-alert 2937], last column). The TA identifications have been
used for the NAS.VSS observations. The sequence - with V magnitudes,
(B-V) colours and R magnitudes - is based on measurements by H. Corwin
and M. Frueh (ref. C&F) and Tsvetkov (Ts, with magnitudes modified by
Skiff). R magnitudes of stars Z and b are approximate and derived by
Skiff from their (B-V) index. The R magnitudes should be used by
observers working with unfiltered CCD.

 *** CHARTS ***
Finder and sequence charts are available from a number of sources, e.g.

* http://vsnet.aavso.org/alerts/alert258/NGC2841-E.GIF (AAVSO)
* http://ftp.kusastro.kyoto-u.ac.jp/pub/vsnet/SNe/sn1999by/99by_c.gif
  (M. Funada)
* http://vsnet.astro.uio.no/~bgranslo/variable/1999by.gif (O. Midtskogen)

*** IMAGES ***
Images by Odd Trondal of SN1999by and other objects are available from
  http://vsnet.geocities.com/SiliconValley/Garage/9531/pictures.htm

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

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