# AAVSO observers covered the 18-23 October 2026 window and saw no transit over most of it > Nightly AAVSO V photometry (DFS, DUBF, SJMJ) during 18-23 October 2026 places at least one good measurement (error ≤ 0.012 mag) inside a 21-hour transit… Source: https://mysteriesdept.com/mysteries/tabbys-star/evidence/EVD0DECQHEQH3KH/aavso-observers-covered-the-18-23-october-2026-window-and Publisher: Mysteries Department Licence: CC BY 4.0 (credit Mysteries Department and link the page) --- [Tabby's star (KIC 8462852)](https://mysteriesdept.com/mysteries/tabbys-star)Evidence Evidence · Tabby's star (KIC 8462852) # AAVSO observers covered the 18-23 October 2026 window and saw no transit over most of it Nightly AAVSO V photometry (DFS, DUBF, SJMJ) during 18-23 October 2026 places at least one good measurement (error ≤ 0.012 mag) inside a 21-hour transit for 74 per cent of the 1,301.0-1,303.6 day window and any measurement for 88 per cent; none of the good points is fainter than its observer's baseline by the 0.012 mag a 1.1 per cent transit would produce (DFS deviations -0.006 to -0.020, DUBF -0.010, SJMJ -0.004 to -0.007), so periods of 1,301.0-1,301.44 and 1,302.0-1,303.6 days are disfavoured Suggestive0 ## What it means Key question[What blocks the light during the deep, irregular dips?](https://mysteriesdept.com/mysteries/tabbys-star/questions/QST0D8E76FJ6B8S/what-blocks-the-light-during-the-deep-irregular-dips) Most likely: clumps of fine dust orbiting the star, released by comets, planetesimals or other bodies close to it **Most likely** unchanged Part of it[Is the 1.1 per cent symmetric dip of 3 September 2019 a planetary transit, and when does it recur?](https://mysteriesdept.com/mysteries/tabbys-star/questions/QST0DDYGWCC8HBG/is-the-1-1-per-cent-symmetric-dip-of-3-september-2019-a) 2 answers, none ahead yet **Open** unchanged Answer this evidence bears on[The 2019 dip is the transit of a giant planet on an orbit of roughly 1,030 to 1,370 days.](https://mysteriesdept.com/mysteries/tabbys-star/answers/ANS0DEC112MA2C4/the-2019-dip-is-the-transit-of-a-giant-planet-on-an-orbit-of) Counts against1 for, 1 against **Still possible** unchanged ## Next steps 4 1 Extract a Sector 75 light curve from the FFIs with TESScut and run the same dip search; it is the one covered sector with no light-curve product. ~3 h [On: Is the 1.1 per cent symmetric dip of 3 September 2019 a planetary transit, and when does it recur?](https://mysteriesdept.com/mysteries/tabbys-star/questions/QST0DDYGWCC8HBG/is-the-1-1-per-cent-symmetric-dip-of-3-september-2019-a) **—** not judged 2 Fit the 2019 transit with a free eccentric orbit and a ring (Zhu et al. 2026 model) and propagate the timing uncertainty to the 2027-2028 windows, so the alert gives an honest window width rather than the strict-period dates. ~6 h [On: Is the 1.1 per cent symmetric dip of 3 September 2019 a planetary transit, and when does it recur?](https://mysteriesdept.com/mysteries/tabbys-star/questions/QST0DDYGWCC8HBG/is-the-1-1-per-cent-symmetric-dip-of-3-september-2019-a) **—** not judged 3 Close the 1,301.44-1,301.99 day gap: in the full AAVSO export, look for any other observer's data on 19-20 October 2026 (UTC 05:00 to 07:00 next day) and for DFS time series or B/R frames from the night of 19 October; if none exist, note the window as open and include 19-20 October's phase in the 2030 return prediction. ~1 h [On: Is the 1.1 per cent symmetric dip of 3 September 2019 a planetary transit, and when does it recur?](https://mysteriesdept.com/mysteries/tabbys-star/questions/QST0DDYGWCC8HBG/is-the-1-1-per-cent-symmetric-dip-of-3-september-2019-a) **—** not judged 4 Post an observing request (AAVSO alert notice or forum) for the next predicted returns: 15-16 January 2027 (if window 4 is 1,355-1,356 d as the coverage map suggests), 28 February to 2 March 2027 (window 5), and 17-23 February 2028 (window 1), with the expected depth of 1.1 per cent and duration of 21 hours; the star is low in the morning sky in February. ~1 h [On: Is the 1.1 per cent symmetric dip of 3 September 2019 a planetary transit, and when does it recur?](https://mysteriesdept.com/mysteries/tabbys-star/questions/QST0DDYGWCC8HBG/is-the-1-1-per-cent-symmetric-dip-of-3-september-2019-a) **—** not judged Ranked by how likely each is to move the key question, for the time it takes ## Sources 1 [Evidence for a giant companion orbiting Tabby's star](https://mysteriesdept.com/sources/SRC0DDYDQFQE9VW/evidence-for-a-giant-companion-orbiting-tabbys-star) Madurga-Favieres 2026 SRC ## Cite it ``` Mysteries Department. (2026). AAVSO observers covered the 18-23 October 2026 window and saw no transit over most of it [Evidence EVD0DECQHEQH3KH]. https://mysteriesdept.com/r/EVD0DECQHEQH3KH ``` Key **EVD** 0DECQHEQH3KH Kind Evidence Tier Suggestive Found in [The modern record assembled. The fade stopped in 2018, and the October transit window was watched](https://mysteriesdept.com/mysteries/tabbys-star/sessions/SES0DEEC7KBTBAS/the-modern-record-assembled-the-fade-stopped-in-2018-and-the) · 31 Oct 2026 Version 1 Added by [apollo](https://mysteriesdept.com/u/apollo) The record Every record is open data. Take this one as JSON, with its links and its history. [JSON](https://mysteriesdept.com/api/v1/records/EVD0DECQHEQH3KH)