🚀 go-pugleaf

On Tue, 7 Aug 2012 05:23:52 -0700 (PDT), dp <dp@tgi-sci.com>
wrote:

>On Aug 7, 5:11�am, Jon Kirwan <j...@infinitefactors.org> wrote:
>> ...(Most of my work was in the
>> visible, near UV, and near IR -- but for very different
>> applications.) I still have some decent setups here and I've
>> designed some devices that can be made for only a few
>> dollars, and wavelength calibrated for $8 more, so that high
>> school students could actually built their own real-world
>> equipment that could genuinely "do science" and meet
>> calibration standards. No intensity calibration, though,
>> sadly. That costs money to do. (Unless you have a suggestion
>> about how to do it on the cheap?)
>
>Oh no, I could not possibly have a suggestion. My spectrometers
>don't seem to have an overlapping wavelength range with yours,
>mine are xray/gamma. I am practically clueless when it comes to
>those in the UV and below range, mine generally count single
>photons.

For all those reasons, that is why I would LOVE to see the
"optics" (and the schematics, as well.) Totally new area for
me to learn about. In my region, it's all about electron
transitions -- and no molecular dissassociation.

I'd expect you'd count single photons at those energies --
just one probably creates quite a shower to deal with. I'd
like to know, in practice, how one measures the energy.

Also, in space there is a serious problem with "brown crud",
which is smashed, charged particles that come from the
satellite's own fabrication scattered into space, which
because it is charged comes back to the spacecraft at some
later time, but sticks elsewhere (not where you want it.) I
don't know if there is a problem with this on Mars -- there
is an atmosphere of sorts. But I'm curious just the same if
there is an accumulation problem and how it is dealt with.

>Efficiency calibration is costly on those for gamma, too,
>though - the calibration source costs thousands. The rest, hm,
>has become much less expensive since the release of the
>netmca-3 (one can still spend tens of thousands on it but
>does not have to any longer).

Now THAT I totally believe. I probably couldn't afford it.
But I still could learn.

>I would be curious what gamma spectrometry the thing is
>carrying on board, too (if any, but likely so). Unlikely
>HPGe, but then who knows, Mars is a cold place, they may
>have figured some practical way to cool things down to
>about liquid nitrogen.

Well, they certainly don't have much atmospheric pressure to
worry about.

Which reminds me of another thing. How do they convect the
internally generated heat away. I recall hearing about
multiple power systems, operating around 32V at near 2A. More
than one. This power must be convected/conducted away -- no
way they want to radiate it. I wonder if they push it
(costing more heat) towards a vane or arm and drag it around
on the surface to get rid of it? The atmosphere won't help
much.

Jon