Do the independent plate archives (Sonneberg, Sternberg, Maria Mitchell) agree with Harvard about the star's brightness from 1934 to 1990?
No evidence yetNothing has been tested yet. Propose an answer, or add evidence.
Where it stands
No answers have been proposed yet.
Why it matters
The century-fade dispute has been fought almost entirely on Harvard's plates, where all post-1962 data come from one series. Three independent archives exist and already disagree: Sonneberg and Sternberg find the star constant to 0.03-0.04 mag per century, Maria Mitchell finds +0.12 ± 0.02. None has been reduced with a pre-registered matched-comparison method, and none has been tested specifically for a 0.1 mag step between the 1950s and the 1970s. Agreement among archives, not more Harvard statistics, is what would settle the parent question.
Answers 0
What would settle it
- Digitise the published 5-year bins from Hippke et al. 2017 (Sonneberg pg and pv, Sternberg) and Castelaz and Barker 2018 (Maria Mitchell) and test each archive for a step of 0.07-0.10 mag between 1930-1953 and 1969-1990 with the same statistic used on DR7; report whether the archives agree with each other and with Harvard.