(CCD image by Yasuo Sano)
Toshihiko Tanaka's prediscovery photograph (Sep. 19) showing the object near 5.5. Very suitable for locating this object with a wide-field instrument.
Unconfirmed bright object(?) in Sgr, please confirm!
Katsumi Haseda (Aichi Japan) has reported possible detection of a potentially bright object (mag about 5.0) at an approximate position 190108.5 -220045 (J2000.0). Since the stellar image was recorded on a single film taken on 2002 Sep. 20.431 UT, the existence or reality of the object has not been confirmed. Although we don't usually report a potential discovery alert at such an early stage, I relay this report because the exceptional brightness clearly requires emergent confirmation.
Could someone check this field?
Regards, Taichi Kato
New object confirmed at position 19 01 09.34 -22 00 05.5 at 09/21/2002 1:35 UT. Position based on plate solution with 20 GSC 1.1 stars. V magnitude greater than 6.3 based on magnitudes in TheSky software. My 20 second exposure was in saturation. I compared two V band images to DSS1.V.SERC V band epoch 1987.59 image. The new object is stellar in appearance and is not present on the DSS1 image. I will continue with photometry and spectrophotometry and report observations when they are reduced.
Regards, Doug West
I confirmed visually, mag. 6.1 on Sep 21.145 at position 19 01 09 (+/-1s) -22 00 05 (+/- 5") using 80 mm refractor f/5 with setting circles. Comp stars SAO 185584 & 187519 & 187422.
Regards Jaime Garcia (GAJ) Rama Caa, Argentina
Additional photometry of the object at 19 01 09.38 -22 00 05.9 error +/- 0.75". This position was measured from a 5 second exposure image. The plate solution used 20 GSC 1.1 stars. B=6.44 +/-0.6, V<6.0 (the 5 second exposure was in saturation). Comparison stars: SAO 187580 B=10.34 V=9.21 and SAO 187591 B=8.98 V=8.75. The images were taken under clear skies with a full moon. I will reduce the low-resolution spectroscopy in the morning and post it on my web page.
Regards, Doug West Mulvane, KS USA http://hometown.aol.com/dwest61506/index.html
Nova Sgr 2002 (No. 3): spectroscopic confirmation by Mitsugu Fujii
Mitsugu Fujii (Fujii Bisei Observatory, Okayama, Japan) reports (via K. Ayani, Bisei Astronomical Observatory) the spectrum of Haseda's new object taken on 2002 Sep. 21.44 UT. The object shows strong Balmer and Fe II emission lines. The FWHM of Halpha emission is 2400 km/s. This observation confirms that the object is an Fe II-class nova shortly after maximum.
Regards, Taichi Kato
The following URL goes to a low resolution spectrum of possible Nova 2002#3. http://members.aol.com/dwest61506/page27.html
The spectrum clearly shows Hydrogen Alpha and Beta in emission. I will be working on a more complete reduction of the spectrum and post the results on my web page later today.
Regards, Doug West http://hometown.aol.com/dwest61506/index.html
We have prepared a chart with 8 x 10 degrees field of this bright nova with comparison stars with VT-magnitudes down to magnitude 9.9 selected from Tycho-2, and placed it at the following URL:
http://www.shopplaza.nl/astro/vs-charts/nova2002-3SGR.htm
http://ar.geocities.com/varsao/Carta_V4743_Sgr.htm
Detailed chart
I've made up a short WWW page describing the discovery of Nova Sgr 2002 (number 3) for the Introductory Astronomy class I'm teaching. It shows the area of Sgr in which the nova occurred, gradually zooming in to the actual spot, and gives people a chance to compare charts with Tanaka-san's photograph to find the nova for themselves.
Anyway, after I made it, I thought that some of the material might be useful for others who might be giving popular talks on the subject in the next few days. Feel free to use it as you wish.
The URL is http://spiff.rit.edu/classes/phys230/lectures/nova/nova.html Enjoy!
Michael Richmond
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