PNV J18225925-1914148: possible nova in Sagittarius (12 mag)

Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Sat, 10/31/2015 - 15:32

PNV J18225925-1914148

Discovered independently by three Japanese observers:

R.A. 18h22m59.25s  Decl. -19°14'14.8"  (J2000.0)
2015 Oct. 31.376 UT, 11.5 mag (CCD, unfiltered)

"2015 10 31.376 UT
Discovered by H. Nishimura, Kakegawa and M. Yamamoto (on Oct. 31.392 UT), Okazaki, Japan, independently, who write nothing is visible on 2015 Oct. 25.382 UT by Yamamoto and on Oct. 28.387 UT by Nishimura. A discovery image by Nishimura at

2015 10 31.3859 UT
This PNV was discovered independently by Shigehisa Fujikawa, Kan'onji, Kagawa, Japan, on a CCD frame taken using a Minolta F 3.5 f 120mm lens. He reported his discovery to National Astronomical Observatory of Japan at 9:57 UTC on 2015 Oct 31, which was before the above discovery was posted on the TOCP page. His frame was taken on 2015 Oct 31.3859 UT and yielded the position end figures as 59s.33 and 06".8 and the magnitude as 11.8."

The possible nova is 32' SE from the Delta Cephei variable Y Sgr.

Clear skies,

Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Nearest USNO-B1.0 star

USNO-B1.0 0707-0560364 (18 22 59.341 -19 14 11.60; R1= 19.73, R2= 21.44) is 1.4" from the position reported by Gianluca Masi.

"2015 10 31.70597 UT
This transient was observed on 2015 10 31.70597 by G. Masi, remotely using the 17"-f/6.8 robotic unit part of the Virtual Telescope Project facility, at Bellatrix Astronomical Observatory in Ceccano, Italy. 120-seconds exposures, unfiltered, show the source at mag. 11.3 (R mags for the reference stars from UCAC-4). We also performed astrometry, getting the following end figures: 59.29; 12.8 (J2000.0, mean residuals of 0.2" on both axes)."


Spectra obtained

From TOCP:

"2015 11 02.417

K. Ayani, Bisei Astronomical Observatory, forwards a report by Mitsugu Fujii (Kurashiki, Okayama, Japan), who obtained spectrograms (R about 500 at H-beta) of this PNV on Nov. 2.417 UT and Nov. 3.389 UT with a 0.4-m telescope of Fujii Kurosaki Observatory. He found a strong and broad H-alpha emission line, an H-beta emission line, He I (501.6, 587.6, 706.5 nm) emission lines, and an N II (567.9 nm) emission line on both nights. The FWHMs of the H-alpha line, measured by Gaussian fitting, are 4800 km/s on Nov. 2 and 4200 km/s on Nov. 3. Fujii's spectrograms are posted at website URL "

Cheers -

Rob Kaufman (KBJ)

American Association of Variable Star Observers (AAVSO)
Nova Sgr 2015 No. 4 in Alert Notice 534

AAVSO Alert Notice 534 announces the discovery and confirmation of Nova Sgr 2015 No. 4. Please see the Alert Notice for details and observing information.

Good observing,

Elizabeth Waagen, AAVSO HQ