Dedicated transmission spectrometer grating for the Seestar S30

 

OpenScad designs for interlocking 3d printed holders
for an 80 lines/mm. holographic printed film grating

" Our instrumentation engineer at the JPO, Jolene Mc Squint-Fleming, has finally got around to designing a transmission grating holder for the Seestar S30. We have had the holographic printed film available for some time but have been thinking through the issues involved before finalising the design of the proto-type holder. 

The Seestar is a little bit of a 'black box' to us at the JPO but the general consensus was that a grating which covered only 50% of the little scope's objective lens was less likely to interfere with the on board 'goto' and 'guidance' software and subroutines. With all prototypes there is an element of try it and see.

The next stage is to refurbish, reset and program the 3d printer in the JPO 'clean room' and have Jolene print the two interlocking elements of the objective lens grating holder. Completing the prototype Seestar S30 stellar spectrometer will then be a straight forward and easy build.

A first light project for the spectrometer prototype is the variable star Cygni34 or P Cygni, which has an interesting spectral profile with a strong H-alpha emission peak.

P Cygni (34 Cygni) is a variable star in the constellation Cygnus. The designation "P" was originally assigned by Johann Bayer in Uranometria as a nova. Located about 5,300 light-years (1,560 parsecs) from Earth, it is a hypergiant luminous blue variable (LBV) star of spectral type B1-2 Ia-0ep that is one of the most luminous stars in the Milky Way". - Kurt Thrust current Director of the Jodrell Plank Observatory.

The variable star P Cygni - data captured some time ago at the JPO using the 66mm Altair Lightwave  ED Doublet on the Star Adventurer EQ mount but reprocessed using SIRIL and Affinity Photo 2.