Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Indus[1] |
Right ascension | 21h 39m 39.3s[2] |
Declination | −70° 28′ 17.4″[2] |
Characteristics | |
Spectral type | F0V[3] |
Astrometry | |
Distance | 3630±110[3] ly (1113±33[3] pc) |
Absolute magnitude (MV) | 2.5[2] |
Details | |
Temperature | 6800±110[3] K |
Other designations | |
2MASS ASAS-SN-V J213939.3-702817.4, J213939.3-702817.4 | |
Database references | |
SIMBAD | data |
ASASSN-V J213939.3-702817.4 (also known as ASAS-SN-V J213939.3-702817.4 and J213939.3-702817.4) is a star, previously non-variable, found to be associated with an unusual, deep dimming event that was uncovered by the All Sky Automated Survey for SuperNovae (ASAS-SN) project, and first reported on 4 June 2019 in The Astronomer's Telegram.[2][3][4]
The star, in the constellation of Indus, about 3,630 ± 110 light-years (1,113 ± 33 pc)[3][5] away, was first observed on 15 May 2014 (UT) by ASAS-SN, and, as of 4 June 2019, has resulted in more than 1780 data points, including a quiescent mean magnitude of g~12.95.[2] On 4 June 2019, the star was reported to have dimmed gradually from g~11.96 at HJD 2458635.78, to g~14.22 at 4458837.45, and, as of 4 June 2019, seems to be returning to its quiescent state of g~13.29 at HJD 2851634.89.[2] According to astronomer Tharindu Jayasinghe, one of the discoverers of the deep dimming event, "[The star has] been quiescent for so long and then suddenly decreased in brightness by a huge amount ... Why that happened, we don't know yet."[4]
DJM-2008
was invoked but never defined (see the help page).AST-20190604
was invoked but never defined (see the help page).AST-20190608
was invoked but never defined (see the help page).TA-20190606
was invoked but never defined (see the help page).CD-20190531
was invoked but never defined (see the help page).