Discovery certificate for object 2018asx
TNS Astronomical Transient Report No. 17717 [ 2018TNSTR.473....1X ]

Date Received (UTC): 2018-04-10 16:11:13
Sender: Mr. Zhijian Xu
Source Group: XOSS

Zhijian Xu, Xing Gao report/s the discovery of a new astronomical transient.

IAU Designation: AT 2018asx
Discoverer internal name: XMr5ZX
Coordinates (J2000): RA = 09:55:52.690 (148.969542) DEC = +68:58:40.90 (68.978028)
Discovery date: 2018-04-09 15:05:10 (JD=2458218.128588)

Potential host galaxy: M81

Remarks: Zhijian Xu and Xing Gao report the discovery of a possible nova in M81. The transient is approximately Mag. 20.6 on severl 300-s survey images (limiting mag about 21.5) taken by Xing Gao in Xingming Observatory Sky Survey(C42) around Apr. 09.62859 UT using a unfiltered CCD (+ 0.6-m f/8 Ritchey-Chretien telescope). The transient approximately located at R.A.=09h55m52.69s +68d58'40".9 (equinox 2000.0). Which is about 104.7" east and 314.1" south of the center of the M81. Nothing is visible at this position on archival images taken on Apr 07.59439 (limiting mag 21.5).NET UCAC-4 XMr5ZX C2018 04 09.62859 09 55 52.69 +68 58 40.9 20.6 V C42.http://www.xjltp.com/XOSS/XMr5ZX/XMr5ZX.htm. Xingming Observatory(C42) - NEXT, Mt. Nanshan, 0.6-m f/8 Ritchey-Chretien telescope and CCD.

Photometry

Discovery (first detection):
Discovery date: 2018-04-09 15:05:10
Flux: 20.6 VegaMag
Filter: Clear-
Instrument: Other
Telescope: Other

Remarks: 0.6-m f/8 Ritchey-Chretien telescope + unfiltered CCD.

Last non-detection:
Last non-detection date: 2018-04-07 14:15:55
Limiting flux: 21.5 VegaMag
Filter: Clear-
Instrument: Other
Telescope: Other

Remarks: 0.6-m f/8 Ritchey-Chretien telescope + unfiltered CCD.

Details of the new object can be viewed here: https://wis-tns.weizmann.ac.il/object/2018asx