PSN J07174570+2320406 2015 05 02.482 * 07 17 45.70 +23 20 40.6 15.7 U 66E 43S N2357 1 0
2015 05 02.482
Discoverd by T. Noguchi, Chiba-ken, Japan, on an unfiltered CCD frame using 0.23-m f/6.3 Schmidt Cassegrain, who writes nothing is visible at this location on his past frame taken on 2015 March 25 UT and the discovery image was put at http://park8.wakwak.com/~ngc/images/PSNinNGC2357.jpg.
2015 05 02.80422
This transient was observed on 2015 05 02.80422 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. 15.4 (R mags for the reference stars from UCAC-4). We also performed astrometry, getting the following end figures: 45.71; 40.9 (J2000.0, mean residuals of 0.1" on both axes).
2015 05 04.1712
Photometry results were V=15.21 and Ic=15.41 with 0.61-m f/6.5 CDK astrograph + FLI PL09000 CCD camera of iTelescope.NET at Sierra Remote Observatory, Auberry, CA, USA, remotely. Seiichiro Kiyota (Kamagaya, Japan)
2015 05 05.406
This probable supernova in NGC 2357 was detected with 5 x 10 min images using a clear filter Photometry: Mag 15.36 +/- 0.18 C (V for ref; USNOA2) Astrometry: RA 07 17 45.71 Dec +23 20 40.5 These data were collected remotely by Joseph Brimacombe, Coral Towers Observatory, Cairns, Australia. Link to image and further information: https://www.flickr.com/photos/43846774@N02/17180015357/
2015 05 16.740
This possible supernova has been imaged at Mandi Observatory Pagnacco-Italy by Paolo Corelli with the 0.4m f:5 telescope + CCD. Exposure: 15 x 45 s unfiltered - mag estimation: 14.8 mV Image link: https://www.flickr.com/photos/52195265@N06/17599305678/in/dateposted-public/
2015 05 09.51874
Mag.=14.8 (R mag for the reference stars from UCAC-4), on six stacked 120-s frames (limit mag.= 16.5) using a 0.30-m f/7.0 Cassegra + SBIG ST-1001E camera (+ I filter) at Osaki Lifelong Learning Center, Japan. Observer Y. Suzuki, T. Yusa, N. Wada, S. Tsunoda and K. Chiba.
2015 05 16.490
V = 14.3, R =14.3 (reference stars from UCAC-4), on each three stacked 120-s frames using 0.30-m f/7.0 Cassegrain + SBIG STL-1001E camera at Osaki Lifelong Learning Center, Japan. Observer T. Yusa, Y. Suzuki, N. Wada, S. Tsunoda, S. Sasaki and H. Goto. VRI color composite image was posted at URL http://space.geocities.jp/yusastar77/supernova/PSNinN2357_150509.htm