Trip Report - Observing with a 22" Obsession UC at 9200' on Mauna Kea, Hawaii

[gary]

The author at the Keck Visitor Center at Waimea.
This is also the headquarters for the Keck and at 800m altitude is a more
comfortable elevation for many of the workers and astronomers to work
rather than being at the summit, where one's judgement can become
impaired. Waimea is the greener transition zone between the dry and
wet side of the island.

The group at the Visitor Center. The place to pick up your Keck T-shirts and caps.

[gary]

Panorama atop Mauna Kea

Author at summit. A beautiful day and the sunshine kept it comfortable
despite the temperature just above the freezing point.

[gary]

One of the other advantages of being on an island with the vantage
point of sunsets over the ocean was that we were able to observe
the celebrated "green flash" phenomena on multiple occasions.

See https://en.wikipedia.org/wiki/Green_flash

It was visible naked eye but observing was dramatically enhanced by using
binoculars.

Thankfully two of our team members had brought with them their Canon
image stabilized binos including a really nice brand-new pair of 18x50's.

A bright green arc would first appear on the left and right side of the circumference of the sun.
This would linger for a couple of seconds and then suddenly the two arcs would join across the top,
creating a bright green rim. The whole event would last possibly 3 seconds in all through
binos and a fraction of that naked eye.

We never tired of watching it and the setting sun signalled it was time
to enjoy a margarita.

[aworley (Alex)]

Wow! Fantastic Gary. Thx for the post!

[RobF (Rob)]

Just wow. Thanks for the fantastic write up of a fantastic trip Gary....!

[Sunfish (Ray)]

One hell of a spot to pitch your tent.

[gary]

Originally Posted by Dennis

Wow - what a fantastic opportunity, thanks for the write-up and stunning imagery from your stay up there.

The scale of the observatory structures really become apparent when you see the parked vehicles and the terrain is other-worldly.

Lucky boy indeed.

Cheers

Dennis

PS - how do motor car engines cope with the reduced atmospheric pressure?

Thanks Dennis,

The internal combustion engines on the two vehicles we used continued
to operate fine above the 10,000' point but of course their efficiency
would be much lower.

The section of road from the 9200' point to the summit changes from
minimally curving tarmac to well-graded gravel with switchbacks.
There is no guard rail but the road is wide but you take it easy.

That last section of road is advised to be 4WD only. You need to engage
a low gear and not ride the brakes. There is less air to cool the brakes
than there is at sea level. There are no shortage of pictures
and videos on the internet where someone has taken up a 2WD and
ridden the brakes coming down and the vehicle has caught ablaze.

For example :-
https://youtu.be/btrqVlCLpVs

One of the vehicles we had also had real-time tyre pressure level
monitoring and they remained normal.

The highway down from the the summit road to the coast - what is
called the Saddle Road - doesn't muck around either. It just goes down
and down and down. You have to remember to swallow every now and then
for your ears to pop otherwise you begin to wonder why everything has
gone so quiet.

There are some emergency truck run-off spots on the Saddle Highway
going down. It's a superb piece of road engineering with a myriad of
cat's eye reflectors. Apparently their use is not as common in the US
as they are here.

Local Hawaiians are protesting about the construction of the Thirty Metre
Telescope (TMT). They had set up a tent city protest camp and were
blocking the road to the summit right up until two weeks before we arrived.
Operations at the observatories had been shut down as a result for 2
months.

The protesters agreed to move their protest to the side of the road
on the proviso that no TMT workers go up to the summit. So our timing
was lucky.

Hawaiian flags flown upside down were a common symbol of protest not
only over the TMT but as desire to secede from the Union.

[Sunfish (Ray)]

Truly paradise for astronomers. Great images and a great experience of seeing. Incredible place for all the sciences . Humboldt heaven.

[gary]

One of the Keck mirror cells inside the mirror lab at Waimea. The mirror
is face down and the complex of levers and actuators can be seen.
An adhesive whose performance had been non-optimal was painstakingly
replaced on the back of each cell where it interfaces with the levers.
A multi-year exercise now nearing completion for the twin 10 metre
telescopes, 72 segments in all.

A schematic of the back of a Keck mirror segment.

Inside the Keck mechanical engineering test lab with actuators on self levelling
workbenches.

Closeup of a Keck actuator.

[strongmanmike (Michael)]

Awesome holiday Gary and wonderful photos very envious. I experienced some exceptional dark skies 3hrs west of Cairns at 17deg South, back at the start of Sept last year and while I wasn't 1/2 way up into t he stratosphere like you we're, it was the first time I had seen the full, zodiacal light, zodical bridge and geguanshein right across the sky from horizon to horizon, spectacular One question, did the potential detrimental effect of Starlink satellites and other similar planned networks come up in you discussions with any in the professional astronomical community?

Mike

[gary]

Originally Posted by strongmanmike

Awesome holiday Gary and wonderful photos very envious. I experienced some exceptional dark skies 3hrs west of Cairns at 17deg South, back at the start of Sept last year and while I wasn't 1/2 way up into t he stratosphere like you we're, it was the first time I had seen the full, zodiacal light, zodical bridge and geguanshein right across the sky from horizon to horizon, spectacular One question, did the potential detrimental effect of Starlink satellites and other similar planned networks come up in you discussions with any in the professional astronomical community?

Mike

Thanks Mike,

The ready appearance of zodiacal light and gegenschein are indeed
excellent metrics for the merit of a dark sky site.

I hope you get the chance to visit Mauna Kea some day. The transparency
is absolutely stunning.

Our primary contacts were with some of the Keck personnel such as
the main mirror lab technician, the head electrical engineer and a staff
astronomer who works with the infrared instrumentation. There was
some brief discussion of Starlink but the main focus of astronomy
politics there is the future of observation on Mauna Kea itself.

Native Hawaiians regard the mountain as sacred and aren't just
opposed to the construction of the Thirty Metre Telescope (TMT)
but all of the observatories up there at present.

The TMT is a US$1.4 billion project and if it does not get built there,
it will be built somewhere else in the world such as the Canary Islands.
However, Manua Kea is regarded as the ideal place.

Currently the TMT has a state supreme court ruling upholding its
construction permit and another state supreme court ruling upholding
the University of Hawaii's sub-lease on the land for the construction site.

Now the battle is shifting to the University of Hawaii's master lease which
covers all the land for all the observatories including Subaru, the Kecks
and Gemini North telescopes.

But the protests go much deeper than just the telescopes and can be traced
back to 1893 when the Hawaiian Kingdom was overthrown.

If you go into a supermarket in Hawaii and for that matter anywhere in
the continental United States. most pineapples and bananas are supplied
by the giant Dole food company. Sanford Dole, of the then Hawaiian
Pineapple Company, led a coup with the help of the American government
over the ruling monarchy back in the 1890's and Hawaiians lost both
their land and much of their culture.

I sense that the protests are largely about that and the telescopes make an easy target.

[gary]

Originally Posted by Hemi

Thanks Gary

A wonderful and enviable report.
ive stargazed with some locals at the top of Haleakala, in Maui, and that was unforgetable, but nothing like your experience.

Thanks Hemi,

How wonderful you got to observe at 10,000' on Haleakala in Maui.

I've been to the summit of Halakala many years ago for the sunrise
and along with so many others had to resort to the blankets borrowed
from the hotel room to stay warm.

Half the space in my pack this time round was devoted to cold weather gear.

The dome of the new Daniel K. Inouye Solar Telescope on Haleakala
was clearly visible naked eye from my bedroom window and from
my front balcony of the rental house we stayed at on the Big Island.

One morning Dave Kriege, who had referred to Google maps, asked us
to estimate how far away it was. A couple of us guessed about 45km.

We were therefore stunned to find that it was over 99km distant!
A testimony to how clean the air is in that part of the world.

With a 26.6m dome diameter, that would correspond to about 55 arc
seconds across. about twice the maximum angular resolution of the
human eye.

[Outcast (Carlton)]

Wow Gary, what an awesome experience...

although... my god it looked cold!!

I wish Cairns would invest in similar lighting technology & policy... for a small town we sure put out some light..

Something to add to my bucket list perhaps... even if it's only taking a small travel scope on holidays there...

Thankyou for sharing your experience

[gary]

Originally Posted by Outcast

Wow Gary, what an awesome experience...

although... my god it looked cold!!

Thanks Carlton,

The freezer suit is definitely recommended with temperatures hovering
around the freezing point. I was comfortable.

However, the afternoon we went up to neighbouring Mauna Loa for
the sunset, I had only packed a sweater and once the sun began to set,
boy did it get cold!

Most of my travelling companions were from the Great Lakes region
where shovelling 20 foot deep piles of snow in their back yards
at this time of year is the norm. So when one of them said to me that
afternoon, "Now it is getting cold!", you better believe it.

As soon as I got back in the vehicle I set my seat heater control to high.
It is often said that keeping your head warm is the most important thing.
But I can testify that if you heat your rump it seems to work equally well.

At the top of Mauna Kea we were lucky as if the wind gets up it can whip
up ice crystals and small lava stones which I am told can really sting.

If you ever get down to the South Pacific Star Party at Ilford, the freezer
suits are common wear there at these latitudes. I always take one
when observing.

But it, woollen gloves, thermal head gear, leather boots with thick
insulating soles and an additional jumper and jacket are not in most
people's packing list for a Hawaiian holiday.

At the 1000' level where the house was, you would be right at home.
Every day was just like the next with a perfect temperature.

I wish Cairns would invest in similar lighting technology & policy... for a small town we sure put out some light..

I wish everywhere would do it!

It is remarkable how little light you actually need to make even a suburban
area safely lit. The monochromatic light makes it easier to filter out
when imaging.

Something to add to my bucket list perhaps... even if it's only taking a small travel scope on holidays there...

Thankyou for sharing your experience

Hope you get to do it some time. The difference between Oahu and the
Big Island is chalk and cheese. The Big Island is more local, far less
people, more rural and very laid-back.

And as an observing location, as good as it gets.

[lazjen (Chris)]

Great write up for what looks like a great trip. Fantastic.

[multiweb (Marc)]

Very cool report and photos to boot Gary. Those lava fields are impressive. The road looks like a carpet laid out on top of black bubble wrap. Amazing to see some shrubs still growing on top of it.

I had no idea there were so many types of actuators at the back of those segments. Must be a lot easier to realuminize them too given their size (just picturing the AAT primary move). I assume they have more segments than the scope primary needs so they can rotate them for maintenance? Are they interchangeable or do they have a very specific base profile for the spot they fit in? Or do they have a "generic" profile then the actuators push it in place depending where they are located in the mirror array? Also if that's the case can they use them on the other primary mirror next door seamlessly?

[xelasnave]

Thanks Gary. Almost as good as being there to read your report.
Alex

[wavelandscott (Scott)]

What a great trip! Thanks for sharing, something else to add to the bucket list.

[big-blue]

Thanks Gary. I enjoyed reading your great write-up of a fantastic trip.

Brought back memories of my own trip up there last year, albeit at the mass-tourism level.
Even so ( for those of us who are not fortunate enough to have your local connections),
I highly recommend the Manu Kea astro viewing tour by 4WD bus that starts with sunset viewing at the observatories,
then descends to 9000ft for viewing of glossies via C11.

An unexpected highlight for me was the spectacular sunset shadow of MK extending many kms over the cloud base below.

The Big Island is an amazing place to visit, on many levels, and deserves to be on everyones bucket list.

[gary]

Originally Posted by multiweb

Very cool report and photos to boot Gary. Those lava fields are impressive. The road looks like a carpet laid out on top of black bubble wrap. Amazing to see some shrubs still growing on top of it.

I had no idea there were so many types of actuators at the back of those segments. Must be a lot easier to realuminize them too given their size (just picturing the AAT primary move). I assume they have more segments than the scope primary needs so they can rotate them for maintenance? Are they interchangeable or do they have a very specific base profile for the spot they fit in? Or do they have a "generic" profile then the actuators push it in place depending where they are located in the mirror array? Also if that's the case can they use them on the other primary mirror next door seamlessly?

Thanks Marc,

Each mirror has 36 hexagonal segments and the surface shape of
a segment depends on its distance from the center. It turns out that there
are six different surface shapes.

So they carry spares which they can swap-out during re-aluminizing.
Each segment is 1.8m across and as you mentioned it is a lot easier to
handle something of that size compared to the logistics of each time they
re-aluminize the 3.8m AAT.

We were given the opportunity to stare down through a glass porthole
into the aluminizing chamber itself and the technician kindly showed us
a high speed video of the aluminizing process where the pellet of
aluminum is vaporized.

The glass itself was manufactured by Schott in Germany and is a material
they trademarked called Zerodur. It has a particularly low coefficient of
thermal expansion, a couple of orders of magnitude better than
borosilicate.

There was a sample of it at the Visitors Center and it is a golden/yellow
transparent color. When you pick it up, because it looks, weighs and
feels different to everyday materials you normally handle, you instantly
know you are holding something "spacey" and different. Even if you
didn't know what it is, because it doesn't feel like glass but is so
optically pure, you would guess it is probably expensive.

One of us (not me) was presented with a small cube of it as a memento.
A beautiful gift and a real talking point.