Barry Fitz-Gerald

Sounds more like a Sect than a Society..............do they have a dress code?

They are a bit agricultral but they function OK, I have them fitted to a SW reflector, a SW ED80 for solar viewing and a 140mm refractor. I do not fit them as per the instructions, but via different home made brackets, and use a small cam belt to run from the pulley on the focuser onto the fine focus knob on the scope. BIt Heath Robinson, but then again I can just slip the belt off and revert to normal focusing if I switch netween EP's or camera. The battery compartment is too small and getting the cover to close over the battery is a faff. Overall it is a good low cost way to eliminate focus wobble - I guess they may not last as long a a premium unit - but they have been in use for 4 yrs or so with no problem.

I really wish you hadn't said that, I can see that I am going to have a lot of trouble resisting one now.

Yes, remarkable images! The CC has intrigued me - looks like a perfect lunar telescope, how do you find it? Is collimation a nightmare?

You might find some useful stuff in the Journal of Skyscape Archaeology published by Equinox Publishing.

This sounds like the same system as on the SW250PDS I have, and it is quite useful. It is surprising how far off the focuser can be, but this allows quite precise alignment with the OTA. I bought a handfull of those small magnetic bubble spirit levels to get the OTA completely level by mounting them along the tube and on the horizintally orientated spider vanes, then used a tightly fitting blanking cap in the focuser with a circular bubble level on top of that. In this way I could ensure everything was level, and usually confirmed it by using a plumb line dangled down through a hole in the blanking cap to check if it was lined up with the vertically orientated spider vanes. Keeping the polystyrene cradles included with the packing helps as this provides a good base to hold the tube horizontal. Fancy for a fairly basic focuser.

Orbiting an M7 Dwarf might be a bit of dodgy place for complex life to evolve what with all those nasty flares, so I am not too concerned about a Mars Attack scenario from that direction. It is nice to see DMS getting some attention after all these years, but of course the detection of Methane, which is a biomarker but unstable and needs to be constantly replaced to be detectable, is also interesting - rather like its detection some time ago on Mars that provoked a bit of a stir. But methane can also be produced by non biological pathways so less exciting than DMS - if it has in fact been detected, which is still up in the air.

You do not an oxygen atmosphere to produce dimethyl sulphide, anaerobic bacteria as well as other others can synthesise it quite happily. If you went back to the early earth say 3billion years ago there would have been dimethyl sulphide in the atmosphere but not a whiff of oxygen - which would have been toxic to most life forms.

.......................probability based on more Statistics https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/abiogenesis-the-carter-argument-reconsidered/BBA3D5F057C5212D76E01F1A0570AB0D

.......................probability based on Bayesian Statistics https://www.pnas.org/doi/10.1073/pnas.1921655117

Well spotted.......... but, Hypothetical means based on possibilities and not reality - not quite the same.

If you are talking hypothetically you explore any possibilities you like - its hypothetical!

It is probably true that we should not expect our familiar biochemistry to crop up all over the universe, but then again maybe the RNA/DNA world was just the most succesful out of many different forms that populated the early Earth, and our microbial ancestors ate all the competition. By the time procaryotes appear in the fossil record, the Earth may have gone through several different forms of life with slightly different biochemical pathways, only for these to be wiped out by impacts during the Late Heavy Bombardment (or the equivalent) and each time life sprang up again and went through the same evolutionary process until only the most succesful solution to replication became dominant. I imagine that on most exoplanets minerals such as olivine, pyroxene, quartz and so on have the same crystallographic configuration as those on Earth, and even more complex hydrated minerals are the same there as here, as there are only limited ways to achieve a stable form with the atomic constituents available. If life also has a similarly narrow range of stable formats, and lets face it life is just another natural process and probably an inevitable one, then maybe the same or very similar biochemistry may be widespread - hence the significance of DMS, if the observations are shown to be correct. The down side of this would be that other worlds may also inevitably give rise to bipedal primates with an overwhelming sense of hubris through converent evolution.

Yes - the 45 degree ones are a pain in the neck, literally for anything over say 50 degree elevation, getting your eyes square on the the EP's becomes more difficult with higher elevations. For terrestrial though they would be more comfortable than the 90's. The 90's are ideal for astro due to the better eye placement at high elevations - for terrestrial they would be uncomfortable. Optically I think they are the same - and I have never had a collimation issue with either the 45's or 90's, but I paid extra for the collimation service prior to delivery. So, if you are just interested in astro use - I would suggest the 90's as the best fit, if you are mixed astro and terrestrial use such as birding then the 45's would be better.

45 degree on a central crank tripod then......................