Affiliation
Association Française des Observateurs d'Étoiles Variables (AFOEV)
Tue, 06/22/2021 - 17:30
ASASSN-21lk (N:/UG:)
https://www.aavso.org/vsx/index.php?view=detail.top&oid=2223219
Recent ASAS-SN Sky Patrol light curve and data:
https://asas-sn.osu.edu/sky-patrol/coordinate/33539ced-d7ca-4dc1-9f7b-b8c6d09da334
No previous brightening in ASAS-SN Sky Patrol or ATLAS data.
Spectroscopy, precise astrometry and multiband photometry (V, B, ...) are required.
Clear skies,
Patrick
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References:
All-Sky Automated Survey for Supernovae (ASAS-SN) Sky Patrol:
- Shappee et al., 2014ApJ...788...48S
- Kochanek et al., 2017PASP..129j4502K
Asteroid Terrestrial-impact Last Alert System (ATLAS):
- Tonry et al., 2018PASP..130f4505T
ASASSNi21lk Sequence is now available...
tough fov with close doubles and many red stars + some
of the faint ones are distant from Target... it is what it is.
Tim Crawford, sequence Team
I managed to catch ASASSN-21lk with a 135mm Samyang telephoto lens - remotely from Chile.
It was was around 13.0TG on June 23.2334UT and 11.6TR on June 23.2350UT. Reddish color. Probably a galactic nova.
Images: https://twitter.com/fidusz/status/1407588671000387584
RGB color image of ASASSN-21lk (2-2x30s with red, green and blue filters):
https://twitter.com/fidusz/status/1407627129425125381
Clear skies,
Robert
Proper ensemble photometry of the two CCD images with green filter (based on APASS DR9 comp stars):
ASASSN-21lk 20210623.2340 UT 13.035 TG (0.016)
ASASSN-21lk 20210623.2356 UT 11.649TR (0.089)
Still brightening? It's around 11.6-11.7TG on a DSLR image made by Rob Kaufman, Australia this afternoon.
See: http://vendegcsillagkereso.blogspot.com/2021/06/novavadaszat-telehold-idejen-asassn.html
Brighter Comps down to ~10.9V are now available
Tim Crawford, Sequence Team
BVI observations of Josh Hambsch confirm, that this is a red variable with B-V=1.4 color index:
https://app.aavso.org/webobs/results/?star=000-BNZ-929&num_results=200
However Timothy Weaver (WTIC) might have mixed V and I filters with I and R, respectively, thus he's got negative (blue) color index. The DSLR photos of Rob Kaufman, Australa also confirms, this is a red variable:
http://vendegcsillagkereso.blogspot.com/2021/06/novavadaszat-telehold-idejen-asassn.html
ATel #14744: Spectroscopic classification of ASASSN21lk/AT2021quw as a Galactic nova
https://www.astronomerstelegram.org/?read=14744