Skip to main content

TCP J18031864-2909223: possible nova (12.8 mag) in Sagittarius

7 posts / 0 new
Last post
SPK
SPK's picture
TCP J18031864-2909223: possible nova (12.8 mag) in Sagittarius

Discoverer: Koichi Itagaki (Yamagata, Japan)
R.A. 18h03m18.64s Decl. -29°09'22.3" (J2000.0)
2016 Oct. 27.3662 UT, 12.8 mag (CCD, unfiltered)

http://www.cbat.eps.harvard.edu/unconf/followups/J18031864-2909223.html

USNO-B1.0 0608-0653867 is 1.2" from the reported position:
18 03 18.584 -29 09 21.33 R1= 26.35 R2= 18.59 mag

Three Initial Gaia Source List stars (of 17 mag) are less than 1" from the reported position.

Spectroscopy of this possible nova is urgently required.

Clear skies,
Patrick

ocn
ocn's picture
TCP J18031864-2909223: possible nova (12.8 mag) in Sagittarius

Hi Patrick,

The following observation does not support an outbursting object in the V band at the coordinates given.

Possible Nova   Oct 27.44   fainter than 15.0V  at coordinates given.

Note:  There is an IR star, IRAS 18001-2909 in Simbad at 18 03 18.70  -29 09 21.4  that may have been recorded in Itagaki's unfiltered patrol image.

best regards,

Steve 

SPK
SPK's picture
Steve O'Connor's observation

Thanks a lot, Steve. Can you post your image here? Did you take any unfiltered images?

Best regards,
Patrick

SPK
SPK's picture
TCP J18031864-2909223 = 2MASS 18031873-2909205

"2016 10 27.367 UT
2MASS 18031873-2909205 J=8.753 H=7.295 Ks=6.454 : K.Itagaki"
http://www.cbat.eps.harvard.edu/unconf/followups/J18031864-2909223.html

This IR source is identical with IRAS 18001-2909 (see Steve O'Connor's comment), WISE J180318.72-290920.7 (W1=5.410, W2=4.799, W3=3.466, W4=2.604 mag), DENIS J180318.7-290921 (I=12.869, J=8.253, K=6.334 mag), and MSX6C G001.7649-03.4476.

So apparently this object is not a nova but a red (variable?) star.

SPK
SPK's picture
Seiichiro Kiyota's follow-up report

2016 10 28.0469 UT
Photometry result was Ic=11.54 with 0.50-m f/4.5 CDK astrograph + FLI-PL11002M CCD, iTelescope.NET at Mayhill, USA remotely. It did not appear in my V image (30sec). Position end figures are 18.70 and 21.12 in RA and Dec. My image is available at http://meineko.sakura.ne.jp/ccd/TCP_J18031864-2909223.jpg
Seiichiro Kiyota (Kamagaya, Japan)

http://www.cbat.eps.harvard.edu/unconf/followups/J18031864-2909223.html

ocn
ocn's picture
TCP J18031864-2909223: possible nova (12.8 mag) in Sagittarius

Hi All,

Sorry Patrick for the delay in responding to your questions regarding this nova imposter. Please see attached V and Ic images with the IR object 000-BMC-441 at center. North is up, east to the left.

Images taken Oct 28.41 UT.  The depicted FOV here is VERY small, only 1 or 2 arc-min. Seiichiro called the Ic mag 11. There appears to be a star near  mag17 in the V at or very close to the position as well which may well be the same object or a visual companion. V-Ic indexes of ~ 6 or more aren't rare. Sgr especially, is loaded with them !   

best regards,

Steve  

SPK
SPK's picture
TCP J18031864-2909223: spectroscopy needed

Thanks a lot for the animation, Steve.

"This object was observed on 2016 11 02.4215 by Sergio Foglia, Paolo Concari, Gianni Galli and Maura Tombelli, remotely using the 0.11m-f/5 reflector of the Tzec Maun Observatory, Siding Spring in Australia. 60-seconds exposures, unfiltered, show the source at mag. 15.2
Image is available at http://asteroidi.uai.it/pub/TCP18031864-2909223.jpg"
http://www.cbat.eps.harvard.edu/unconf/followups/J18031864-2909223.html

Hopefully spectroscopy can be performed before solar conjunction on 22 December.

Patrick

Log in to post comments
AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484