Calculation of rotational speed and diameter of Jupiter [2015-03-17]

The spectrum is made along the equator of Jupiter (Slit aligned to the equator, look at image below).

You can see the terrestrially atmosphere lines exact vertically, but the Doppler shifted lines from sunlight reflected on Jupiter are slantwise.

Over the difference of wave length it is possible to calculate the rotational speed of Jupiter and with the known rotational periode of 9 hours 50 minutes and 30 seconds we can calculate the diameter.

The diameter calculated on the sharp Ni 6643.64A line is 139184km, this is only 2.7% smaller than the real value of 142984km (wikipedia).

     
Telescope: Officina Stellare RC360AS, f/8, d=360mm processed with BASS project Download cropped and integrated spectral stripe:  Jupiter_6min_19p0_rotated_slant_crop.fit
Spectrograph: Lhires III, 2400gr, slit 23u Calibrated with known spectral lines Download RAW (17MB): 2015-03-17_Jupiter.zip
Camera: SBIG ST10-Xe 6 images (6 x 60s) Download BASS project bundle: Jupiter_rotation.bun
Resolution: 0.089 A / pixel, resolving power ~ 17000 Dark corrected, cropped, and stacked with PixInsight  
Acquisition software: SbigControl Guiding software: DMKguider    
Date: 17. March 2015, UTC 21:13 - 21:21    
Jupiter