Mintaka (34-Delta Orionis): Double Star in Orion • SCT 8" f/10 • 200mm Celestron widefield eyepiece • 100x • 12 January 2010 • 20:30 UT • Seeing 7/10 • cloudy
This is my first attempt to sketch a binary star according to the technique used by Jeremy Perez.
There are still a lot of things to master, including the representation of the relative magnitudes as well as astrometry to accurately monitor angular separation.
Mintaka is the westernmost star of the three belt stars of Orion, also known as Delta Orionis. It is a beautiful double star. The companion star is located 52.6" almost due north of the primary in position angle 359°. Both stars were seen as whitish blue.
RA = 5 h 32 m 0.4 s Dec = - 0 ° 17 ' 56.7 ''
(Equatorial coordinates - epoque J2000 - ICRS)
Color index B-V : -0.17
Spectral class : O9.5II
The separation between the two components of Delta Orionis made it fairly easy pair to separate in spite of the brilliance of the primary star. I used a 20 mm Celestron Plossl eyepiece (100x) for the sketch shown here on the left.
Mintaka has been known since antiquity. Its duplicity was documented in F. G. Wilhelm Struve's first supplement to his famous catalogue and bears the designation STF I 14.