What is being checked?
This tool compares tropical ecliptic longitudes within a one-degree orb. A match with the Midheaven is not proof that the star was physically culminating: its latitude and declination matter for that separate question. This is not a paran calculator.
Which stars and which method?
Sirius (Alpha Canis Majoris), Deneb (Alpha Cygni), Aldebaran (Alpha Tauri) and Antares (Alpha Scorpii). SIMBAD J2000 coordinates and proper motions are rotated to the birth-date ecliptic with Astronomy Engine. No stellar parallax or radial-velocity correction is applied; values are rounded to hundredths of a degree.
Sources : SIMBAD, CDS · Astronomy Engine