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(IAAC) Supernova observations, April23/24 1998





Observations on SN 1998aq, SN 1998S 20" F4.4 Newtonian on Dobsonian mount,
Sky clear limiting magnitude 6
Object   name   Julian date      Magn.            Compstars       Chart

SN 1998aq   -  2,450,928.5000    122             121 122 124 130  AAVSO  
SN 1998S       2,450,928.5000    130             125 126 132 136  AAVSO

1998S has not changed noticeably in brightness over the 3 day period and
remained distinctly brighter than the neighbouring 13.2 magnitude star on
the AAVSO provisional comparison chart.
1998aq has brightened by 0.4 magnitude at least by my estimate.
The other supernova in Ursa Major 1998T in NGC3690 is now extremely elusive
with my 20". Following reading the article on telecopic visual limiting
magnitudes by Schaefer(1990)  suggested by Jeff I am reasonably confident
about my observation of the 20/21 April. On April23/24 the object was seen
for brief spells but was even more elusive so must be at about my limiting
magnitude using the 20".
Nick
(Bradley E. Schaefer,(1990)  Telescopic Limiting Magnitudes. Publications of
the Astronomical Society of the Pacific vol 102, 212 - 229 obtainabble from
NASA Astrophysics data system on URL {NB.fit on one line}
http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1990PASP%2E%2E1
02%2E%2E212S&page=1&plate_select=NO&data_type=GIF&type=SCREEN_GIF