[vsnet-campaign-dn 15516] ASASSN-21et = TCP J06154200-2756220: likely dwarf nova outburst (mag. 12.3, in Orion)

[Patrick Schmeer pasc1312-aavso@yahoo.de via vsnet-campaign-dn]

ASASSN-21et = TCP J06154200-2756220  (UG:)
(submitted to VSX)

ASASSN-21et was noticed by the ASAS-SN team more than 15 hours ago and
details will soon appear here:
http://www.astronomy.ohio-state.edu/asassn/transients.html

Complete ASAS-SN Sky Patrol light curve and data:
https://asas-sn.osu.edu/sky-patrol/coordinate/4a3d1002-ca6a-4790-98c1-317cf494b405

TCP J06154200-2756220  2021 04 02.4453*  06 15 42.00 -27 56 22.0  12.5 U  CMa
"2021 04 02.4453 UT
Discovered by Yuji Nakamura, Kameyama, Mie, Japan, on two frames (30-s exp.,
limiting mag 15.0) taken by 10cm/F3.0 refractor and CMOS camera. Nothing is
visible at this location on the frames taken on 2021 Mar. 25.4610 UT (30-s exp.,
limiting mag 15.0) by same instrument."
http://www.cbat.eps.harvard.edu/unconf/followups/J06154200-2756220.html

Looks like a large-amplitude dwarf nova outburst (WZ Sagittae type?).
The likely progenitor is
Gaia EDR3 2899277163034558336 (Gmag. 20.22; parallax 2.8163±0.5076 mas) =
PSO J061542.121-275624.556 (gmag. 20.2, rmag. 20.2) =
GALEX J061542.1-275623 (FUVmag. 21.1, NUVmag. 20.7) =
WD J061542.13-275624.78 = ...

Time-resolved photometry is urgently required.

Clear skies,
Patrick
-------
References:
All-Sky Automated Survey for Supernovae (ASAS-SN) Sky Patrol:
- Shappee et al., 2014ApJ...788...48S
- Kochanek et al., 2017PASP..129j4502K