Mon, 04/12/2021 - 18:23
Complete ASAS-SN Sky Patrol light curve and data: https://asas-sn.osu.edu/sky-patrol/coordinate/f9c61af9-11cb-4857-9663-35c8b21633b9
Transient Name Server: https://www.wis-tns.org/object/2021jiu
Spectroscopy, multiband photometry (V, B, ...), and precise astrometry are urgently required.
All-Sky Automated Survey for Supernovae (ASAS-SN) Sky Patrol:
- Shappee et al., 2014ApJ...788...48S
- Kochanek et al., 2017PASP..129j4502K
Photometry result was B=10.635. Position end figures 08s.11, 40".9 measured with a 0.50m f/6.8 reflector + FLI-PL6303E CCD camera at Siding Spring, Australia (T30, iTelescope.NET).
Unfortunately the 10s V-band images were already saturated, but visual inspection of the images showed the nova candidate slightly brighter than 9.0 magnitudes. Thus B-V seems to be at least 1.5 magnitudes. The variable is indeed very red.
Robert Fidrich (Budapest, Hungary)
Edited by Carlos Adib (ACN)/sites/default/files/users/user63588/7846%20-%20DET%20-%20NV%20SCO%2021-.jpg
Follow-up observation: 2021 Apr. 13.78683 (JD 2459318.28683) UT. Mag.= 8.53 TG +/-0.05 using Canon EOS 60D camera, focal length 135-mm, f/5.6 (stacked 5x5 sec., ISO-6400). Haze. Filipp Romanov (Yuzhno-Morskoy, Nakhodka, Russia). My photo (stacked 115x5 sec.): https://www.flickr.com/photos/filipp-romanov/51114244018
Added low-resolution spectrum (480) of object to AVSpec; high airmass for my location.
ASASSN-21fh (Nova Sco 2021) has been assigned the GCVS name V1710 Sco: http://www.cbat.eps.harvard.edu/iau/cbet/004900/CBET004955.txt (behind paywall)
This nova was officially (and solely) discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN) – although something else is claimed in CBET 4955.
V1710 Scorpii in the International Variable Star Index: https://www.aavso.org/vsx/index.php?view=detail.top&oid=2217653
AAVSO Alert Notice 740 reports on V1710 Sco = N Sco 2021 (= ASASSN-21fh = PNV J17091000-3730500). Please see the notice for details and observing instructions.
There are threads for this object under the following forums:
- Time Sensitive Alerts: https://www.aavso.org/asassn-21fh-possible-nova-mag-104-scorpius-0
- Novae: https://www.aavso.org/asassn-21fh-possible-nova-mag-104-scorpius
Please subscribe to these threads if you are observing this nova so you can be updated as to its behavior and any observing campaigns on it. Join in the discussion or ask questions there!
Many thanks, and Good observing,
Elizabeth O. Waagen, AAVSO HQ