Saturday, May 05, 2018

more time with 11 LMi (Halifax)

I commanded the Burke-Gaffney Observatory to image double star 11 Leonis Minoris aka HU 1128. I had not seen the B partner on the evening of 16 Mar '18 with my C8. Centred on GSC 02500 00282.

double-star 11 LMi in luminance

Luminance only, 1 second subexposures, 20 stacked shots. FITS Liberator, GIMP. North is up; east is left.

The image below is a detailed crop for the region of interest.

detail of 11 LMi with B visible

I believe the incredibly faint B companion is visible at the 10 o'clock position, up and left, or north-east of the primary.

B is opposite the star J093534.0+354722 which SkyTools shows is magnitude 14.87. Curiously this dim stars appears to be in a pair with J093533.3+354741 to the north west at mag 15.03. The 11 LMi B element looks dimmer! No wonder I couldn't see it from the backyard. ST3P, by the way, says these stars are 21" apart.

Wikipedia says B is mag 12.5 as does the WDS. SkyTools 3 Pro says 14.0. Maybe it is bright but very close so lost in the glare.

There is a fantastic, interesting tight faint pair of stars far to the north-north-east. ST3P only shows a mag 11.4 single star GSC 02500-0848. Wow. The tight pair is about half the separation as the pair to the south-west, opposite 11 LMi, so about 10".


Some additional notes, or said a different way, for clarity.

11 LMi data:

heading mag A mag B PA° (θ) sep" (ρ) as of
SkyTools 3 Pro 5.41 14 49 6.60 2020.3
Stelle Doppie 4.8 12.50 61 6.7 2012

It has an indeterminate Orbit, with a period (P) of 201.0 years and semi-major axis (a) of 3.84".

Note: the ST3P PA and Sep is calculated or predicted.


Tried again on 28 Dec '20 but it didn't go well...


Wikipedia link: 11 Leonis Minoris.

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