Was just looking at the new TESS data when I happened upon this very unusual star, HD 45059, which does not seem to be identified as a variable, varying by something around 0.10-0.15 magnitudes. Or about 12% of its total brightness, I'm not usually a variable star expert so I'm not sure how it translates. Here are the light curves, axes given in days and percentage variation:
https://panoptes-uploads.zooniverse.org/production/subject_location/27b1ad9d-69d3-4dc4-8c23-c13eee72a44b.png
https://panoptes-uploads.zooniverse.org/production/subject_location/7e6be314-3595-498e-a8a9-18094334c21e.png
https://panoptes-uploads.zooniverse.org/production/subject_location/47f515cd-12f3-4bfa-a2bd-a2464cc5a260.png
https://panoptes-uploads.zooniverse.org/production/subject_location/c464b1b2-1f19-499a-93cd-22f5dc54da05.png
The primary star is an A9IV star, both inferred from Gaia observations and directly measured from a 1975 spectrum. It's located 2.27 arcseconds away from a ~G4V solar-like star, which based on the motion and parallax is most likely related. At its distance from the Sun, the G4V star is at least 400 AU from the A9IV. Judging by the proper motion difference, their orbit is probably close to face-on.
I've searched over all of the variable stars I knew of, and I can't name any A9 stars that vary to this magnitude over a period of only a few hours to a couple days. Can anyone help?