Electronic Telegram No. 2265
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Room 209; Dept. of Earth and Planetary
 Sciences; Harvard University; 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbat@iau.org; cbatiau@eps.harvard.edu
URL http://www.cfa.harvard.edu/iau/cbat.html


NOVA SCORPII 2010 No. 2
     Further to CBET 2262, S. Nakano, Sumoto, Japan, reports an independent
discovery of this presumed nova at mag 8.8 by Yukio Sakurai (Mito,
Ibaraki-ken, Japan) on two 20-s frames (limiting mag 10.2) taken on Apr.
25.734 UT using a Fuji FinePix S2 camera and a Nikon 180-mm f/2.8 camera
lens; Nakano measured the position from Sakurai's jpeg image to be R.A. =
16h55m13s.07, Decl. = -38d03'45".3 (equinox 2000.0; probable error +/- 3").
Nothing was visible at this position on a similar frame taken by Sakurai on
Apr. 24.74.
     S. Kiyota (Tsukuba, Japan) reports that he obtained CCD images with the
30-cm GRAS-001 (Global-rent-a-scope) reflector located near Mayhill, NM, USA,
yielding the following precise position for the apparent nova:  R.A. =
16h55h13s.22, Decl. = -38d03'46".8 (equinox 2000.0), and the following
magnitudes:  Apr. 26.307 UT, V = 8.55; 26.308, R_c = 7.75; 26.309, I_c =
6.92; 26.310, B = 10.18.
     E. Guido and G. Sostero write that they obtained unfiltered CCD images
remotely through a 0.25-m f/3.4 reflector at the GRAS Observatory near
Mayhill, NM, U.S.A., on Apr. 26.4 UT, showing the variable at mag about 8.2
with position end figures 13s.17, 47".8.  They have posted an animation
showing a comparison between their own image and a red Digitized Sky Survey
plate from 1995 at website URL http://bit.ly/axetYA.
     H. Koberger, Vilaflor, Tenerife; and W. Vollmann, Vienna, Austria,
report mag 10.3 and position end figures 13s.16, 46".9 from a DSLR green-
channel image taken by Koberger using a 0.6-m reflector on Apr. 27.21 UT.
A low-resolution spectrogram with 100 lines/mm using the same telescope
on Apr. 27.199 clearly shows H-alpha emission in the nova spectrum.
     H. Maehara, Kwasan Observatory, Kyoto University, reports that a low-
resolution spectrogram (range 400-800 nm) of the variable was taken on
Apr. 29.704 UT with a 25-cm telescope at Kwasan Observatory.  The spectrum
shows H_alpha and H_beta emission lines with a FWMH of 4000 km/s.  The
spectrum has been posted at the following website URL:
http://www.kwasan.kyoto-u.ac.jp/~maehara/novae/SCOnova2010no2_20100429.png.
These features suggest that the object is a classical nova.  CCD images
obtained with a 25-cm telescope at Kwasan Observatory yield the following
magnitudes:  Apr. 29.680, I_c = 8.77; 29.681, R_c = 9.45; 29.683, V =
11.21; 29.685, B = 12.03.
     Visual magnitude estimates:  Apr. 27.154 UT, 11.0 (A. Amorim,
Florianopolis, Brazil); 27.692, 9.8 (Y. Maeda, Nagasaki, Japan; via
Maehara).


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2010 CBAT
2010 April 30                    (CBET 2265)              Daniel W. E. Green