AT2026tim (LSST ID 170631094842425480) was initially identified as a fast and red optical transient in the LSST alert stream (AstroNote 2026-212). AT2026tim was first detected on 2026 July 06, at 06:42:43.7 (07:49:41.5) UTC by LSST at i (z) = 22.8 (22.4) +/- 0.15 (0.12) mag, fading 0.71 +/-0.16 magnitude in i-band over the following two nights.
We observed AT2026tim on Keck/LRIS at 2026-07-11 10:34:40 UTC. The transient is well detected with a spectrum dominated by absorption features. We identify strong Na I absorption at a redshift of 0, as well as various other absorption features [Ca II]. The shape of the spectrum and the associated lines matches the template of a late K-type star. We conclude that the reported transient is most likely the result of stellar variability.
| Catalog | Name | Reported RA | Reported DEC | Reported Obj-Type | Reported Redshift | Host Name | Host Redshift | Remarks | TNS RA | TNS DEC | TNS Obj-Type | TNS Redshift |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TNS | 2026tim [170631094842425480] | 20:07:41.012 | -29:34:37.01 | 20:07:41.012 | -29:34:37.01 |
Comments