Re: St Veran gravity red-shift misson
Dear Christoffer,
Many thanks. Yesterday we maanged to drive from Grenoble up into St
Veran village, the highest village in Europe. This had me driving
mountain roads like nothing I've ever done before, so it was a very
intense experience. I even drove through Italy, so the second new
country for me to drive in.
From St Veran village my car was not suitable, as the final climb is on
a road which is not very good, so we had to use the Observatory jeep and
transfer the clock over to the shock absorber. This is quite an
elaborate dance, but thanks to the modularity of the setup where where
able to safely transfer it up. We used a small pin-wheel antenna to
record the remaining rise.
At the observatory, I made sure that batteries was recharged before we
transitioned furteher. It was quite an elaborate dance to move it up
into the lab. We also installed a choke ring antenna on the roof of the
observatory.
I use my Mosaic-T and ORB brought their PolaRx4TR. This provide
redundancy, which is good, since we discovered that the cable from the
antenna-splitter over to the PolaRx4TR can have a loss of contact.
Having spare cables and adapters have helped, so we had to be a bit
innovative to extend the cable, but I weather secured the extension
setup, so we should be fine.
We maintained the cesium operational from Grenoble. I will investigate
when we lost state, but it was before Grenoble, so we should have good
data from that, even if Cesium date and time is off, we do not measure
that so I can adjust that later today.
I now go into a clean-up, so start additional loggings I did not managed
to start manually because of stress. I aim to make those autostart, it's
not hard, but one had to prioritize hard. Power to the cesium is key,
GNSS recording operational second, then logging of cesium, environment,
PV & batteries further down the line. The key to mission have been
achieved. I can clean up the other stuff while here. I want that
additional environmental and system logging to work for the rest of the
mission.
So, we have not failed the mission yet. It's not been perfect, but with
some clean-up action and experience built, we can improve robustness.
The Observatoir de Saintt Veran is originally built for Observatoir de
Paris, and they used to have two domes in Paris, but the light poultion
makes it fairly useless. So, they built this observatory and moved one
of their domes up here. Yesterday late, they where walking to that dome
saying "Want to see Saturn?" and I just tagged along. It was not the
best of days, since it was very windy and that makes the atmosphere more
disturbed. But the night sky here is spectacular.
Another nice thing here is that up here there is a small animal called
Marmote. I've never seen one, even in zoo, and on the drive up we could
see plenty of them. These are very shy animals, so they run away as we
came driving up. However, occasionally they come up to the observatory.
Just the other day, one Mermote walked over the observatory keepers
foot, not run, but walked. So, we joked that the Marmotes do not fear
the scientists. :)
We where able to come up with the clocks a day early, so we got to
interact with the previous mission. Friendly and hospital people. So
they shared the reminder of their dinner food, cheese and wine with us.
The hobbyist astronomers can apply for one-week missions to Astro
Queyras that. Depending on the quality of the mission, they get access
to the site for a week, and good mission gets the good weeks, with
minimal moon light polution. Normally it is full isolation, but gaining
another day of integrating up the frequency error they bent the rules
for us, and me and Bruno could come early. We are very happy as we also
got to interact with the preivous mission here.
If there is interest, I can keep sending updates. Yesterday was hectic,
so it was not the time to pull out data. That work we can start doing
today. I will also do a write-up of the setup if people are interested.
So, I was given the oppertunity to do this with very short notice, and I
jumped on the oppertunity. It's been very stressful and hard work to
come to this point, but now I can start to enjoy it. Also, time to share
the experience.
Today will the rest of the total mission come up, I only work on the
graviational red-shift mission, but the full mission involves astronomy
missions naturally, such as spectroskopy. There is also a documentation
side, so things is filmed etc.
Cheers,
Magnus
On 2023-07-16 06:48, Christopher Hoover wrote:
Best of luck, Magnus.
On Fri, Jul 14, 2023 at 4:04 PM Magnus Danielson via time-nuts
time-nuts@lists.febo.com wrote:
Fellow time-nuts,
So, 5 years ago I was asked by Observatoir Royal de Belgique to take
care of two failed 5071A cesiums and alter them so that there is one
functioning. I did that, and have operated the functioning one
here and
there, but conservatively, since they wanted to do a mission with
graviational red-shift.
Since them, other things happen in life, such as Covid, prohibiting
work. However, a few weeks ago I was contacted as they where about
to go
on the mission. I thought it would be nice to join, as I had quite
a bit
of the things needed for such mission.
Setting it up meeds a number of challenges, as it needs to be powered
continuously, and over a varity of sources.
In addition I wanted to log as much data as possible. I've come
far on
that point. I log 5071A state and several other environment
sensors into
an InfluxDB and then illustrate with Grafana. Independently two GNSS
receivers log things for post-processing.
Just assembling the rig for the two 100 W PV panels and a choke-ring
antenna has been a challenge. Let's just say that I should not be
hired
to do fine mechanics work.
Things have been fixed during the travel, and I have driven
600+1100+800
km just to be in base-camp before final climb. I'm now sitting in a
borrowed house just outside of Grenoble. I just had to tear out
part of
the equipment, as one of the power converters failed. Luckily that
side
was redundant for the mission, but I do miss one pressure sensor to
compare the small one with.
I had intended for my passive hydrogen maser to also do the trip,
but it
woke up with an unexpected problem and did not lock, and I decided it
was not meaningful to bring it's dead weight along. I will have to
investigate the actual fault. Also, I have been unable to log the
internal state, which Would have given valuable clues.
Tomorrow we do the final climb to Observatoir de St Veran at 2930
m and
stay there for 8 days.
Connectivity can be sketchy.
In the end of the day, it is only if you try that you can either
fail or
succeed. So far, it has not yet failed completely catastrofically,
but
warnings-signs has gone of and they been managed, so far. This can
still
fail spectacular.
Now I badly need my bed. Being sleep deprived does not help thinking.
Cheers,
Magnus
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