As announced in IAUC 7108, SN 1999aa was discovered by Ron Arbour on 1999 Feb 11.0166.
North is up and east to the left.
And here is an R-band image of NGC 632 on 22 Aug 1999 UT with a a sequence of stars indicated. This sequence was calibrated by Kevin Krisciunas from images taken on 22 Aug 1999 UT with the MRO 0.6-m telescope. The positions were determined by Brian Skiff from the USNO-A2.0. The last data point is a bona fide R-band magnitude. Here is a light curve of the supernova 1998dh in NGC 7541, obtained with the 0.6-m Schmidt telescope of Lowell Observatory at Anderson Mesa, near Flagstaff, Arizona.