[vsnet-alert 2924] SN 1999by in NGC 2841

[Hitoshi YAMAOKA <yamaoka@rc.kyushu-u.ac.jp>]

cf. vsnet-chat 1843
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-chat/msg01843.html
cf. vsnet-chat 1844
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-chat/msg01844.html
cf. vsnet-chat 1845
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-chat/msg01845.html
cf. vsnet-chart 151
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-chart/msg00151.html
cf. vsnet-obs 20407
http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Mail/obs20000/msg00407.html

Dear SN watchers,

  Following SNe 1999bw and 1999bx, the remarkable SN has discovered by
British amateur R. Arbour and LOSS KAIT team independently.  This new
object, named as Supernova 1999by, is in brightening phase, and will
potentially reach the brightness which can be easily caught by small 
(say, 5') telescopes. 

  IAUC 7156 tells that the position of SN 1999by is: R.A. =
9h21m52s.18, Decl. = +51o00'07".2 (by KAIT team), which is about 100"
west and 91" north from the core of the host Sb galaxy NGC 2841.  The
foreground stars near SN are there: 

                 R.A.      Decl.    offset from SN  mag(about)
GSC3431_625  9h21m50s.8 +51o00'36".5  12"W,29"N     11
GSC3431_053  9h21m47s.4 +50o58'50".3  45"W,78"S     13
GSC3431_495  9h21m58s.3 +51o00'15".8  58"E,8"N      14
unnamed(*)   9h21m54s.6 +51o00'16".9  23"E,10"N     17

(*) is potentially a condensation in NGC 2841.

  There seems some systematic errors in USNO magnitudes, and also in
GSC magnitudes.  The photometric (magnitude estimating) observer
should use the sequence kindly provided by Prof. Skiff (vsnet-alert
2917, 2919) for the comparison.  

  NGC 2814 has produced (at least) three supernovae in this century.
Among these three, only one, 1957A, was observed around its maximum at
B = 14.  It has been classified as a peculiar type I supernova.  Other
two had been missed their maximum.  

  NGC 2814 is about 0.7 mag nearer than Virgo center (M 87).  Thus the
typical SNeIa in this distance will have about 11.5 mag at their
maximum without absorption.  Now 1999by is in a rapidly brightening
phase, so the followup observations (includeing spectroscopy) are
extremely urged. 

Sincerely Yours,
Hitoshi Yamaoka, Kyushu Univ., Japan
yamaoka@rc.kyushu-u.ac.jp

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp