. . . and that, at about the suggested time for an up-turn.
Astronomy telegram clip:
>>The Fall and Rise in Brightness of Betelgeuse
ATel #13512; Edward Guinan, Richard Wasatonic (Villanova University),Thomas Calderwood (AAVSO) and Donald Carona (Texas A& M University)
on 22 Feb 2020; 12:59 UT
Credential Certification: Edward Guinan (firstname.lastname@example.org)
As previously reported (see ATel #13365, #13410 and #13439), the red supergiant Betelgeuse has been undergoing an unprecedented decrease in its visual (V) brightness since October 2019. Photometry secured over the last ~2 weeks shows that Betelgeuse has stopped its large decline of delta-V of ~1.0 mag relative to September 2019. The star reached a mean light minimum of = 1.614 +/- 0.008 mag during 07-13 February 2020. This is approximately 424+/-4 days after the last (shallower: V ~ +0.9 mag) light minimum was observed in mid-December 2018. Thus the present fading episode is consistent with the continuation of the persistent 420-430 day period present in prior photometry. Three recent observations made at Wasatonic Observatory, carried out on 18.15 UT, 20.1 and 22.07 UT February 2020, returned V = +1.585 mag , +1.574 mag, and +1.522 mag, respectively. Photometry carried out by D. Carona on 18.2 UT February 2020 returned V = +1.589 mag. In addition, Wing TiO band and near-IR measures (and corresponding temperatures and luminosities) also reached minimum values during mid-February 2020. Photometry carried out by D. Carona (Texas A&M Univ.) on 18.2 UT February 2020 returned V = +1.589 mag. Also T. Calderwood’s recent observations given on the AAVSO website (https://www.aavso.org/lcg) are: V = +1.589 mag, +1.567 mag and 1.556 mag, respectively on ~17.2, 19.2, 20.2 UT February 2020. Based on these and additional observations, Betelgeuse has definitely stopped dimming and has started to slowly brighten . . . >>
Looks like we won’t get to see some celestial fireworks just yet. (They still suggest up to 100,000 years.) END