Mauna Kea – Page 36 – A Darker View

Venus Transit on Mauna Kea

A Venus Transit is a truly rare event. Transits occur in pairs eight years apart, with the next pair not occurring for another 120 years. The first event of the current pair occurred in 2004. Thus the next event will happen in June 2012. Considering the century long period between events, this is the last chance to witness a Venus transit during our lifetimes.

The 2012 event will be visible from the west coast of North America to Japan, China, Australia and Central Asia. For those wanting to observe the entire event from start to finish the choices narrow quite a bit. You have the choice of the Central Pacific, Japan, as well as Eastern China and Eastern Australia. This, of course, includes here in the Hawaiian Islands.

Many sky-watchers from North America will see only one choice if they wish to observe the event… the Big Island. The only place easily accessible by air, featuring excellent visitor accommodation, and an observing site that sits above the clouds that could so easily interfere with carefully laid plans. For the serious observer there is one obvious choice… Mauna Kea.

We saw the first signs of this well over a year ago. The tour companies that specialize in astronomy related travel, the folks that feature solar eclipse tours and similar events, began scouting Mauna Kea as a destination. Then the ads appeared, in Sky & Telescope magazine, Astronomy magazine, etc., “See the transit from Mauna Kea!” We had fair warning that this event was not going to pass peacefully.

Visibility chart for the 2012 Venus transit, image credit: Fred Espenak/NASA

Some folks seem to think the crowd will be huge, a thousand people or more. I am not so certain, this does not have the general appeal of a total solar eclipse. The transit is something that will be of interest to amateur astronomers and some interested segments of the public. I personally expect hundreds of people coming to Mauna Kea to view the transit, not thousands.

However many folks do ascend the mountain for this event, we have begun putting plans in place to handle it. Various groups have met to do a bit of planning. Most significantly, those in charge of managing the mountain, The Office of Mauna Kea Management, are putting a few measures in place. As usual, expect to stop at the Mauna Kea Visitor Information Station on the day of the transit. But this day there will be a few differences…

All available MKSS staff will be on duty. All of the Mauna Kea rangers and visitor station staff will be helping make sure assistance is available to visitors when traveling to the high altitude environment of the summit.
Access to the mountain will be controlled for the day, a gate at the VIS allowing access for official vehicles only.
A free shuttle will run from the VIS to the summit. The Mauna Kea tour companies providing the vehicles and drivers.
Solar telescopes and video monitors will be set up at the VIS to allow safe viewing. Staff will be available to answer questions and assists with the equipment.
Several other locations on the island will be setup for viewing the transit with solar telescopes and staff. Expect these to include ‘Imiloa, Keck HQ in Waimea, and some possible other locations.

All of these plans are somewhat preliminary, details may change as the date approaches and final arrangements are made. I will attempt to post what I know here on Darker View.

Myself? I plan to observe the event from the summit. Set up behind Keck with a solar telescope to photograph the transit. We plan to set up a live feed of the transit for use by other sites, and available to viewers across the internet.

Dispatch from the Summit – Chaining Up

By all accounts it was bad.

I was scheduled to go up, but ended up not joining the summit crews today. Just as well, they did not make the summit. The crew made it partway up, to about 12,000ft., into snow and freezing rain. Not a lot of snow, but a lot of slick ice, altogether much worse.

I talked to a few guys and the descriptions ranged from nasty to miserable. Pete remarked that his hair and pants were slowly icing up in the freezing rain. Kirk recalls parking the pickup to put on the chains, when getting out Michaela noted the vehicle was still moving, sliding sideways on the ice.

The road is closed to all vehicles! This is quite unusual, normally it is closed to the public when bad weather dictates, but remains open to observatory vehicles. Our trucks are some of the few vehicles on the island equipped with bad weather kits that include chains and other useful gear for dealing with ice and snow. Watching island boys with no winter weather experience trying to drive on ice can be rather entertaining.

I am scheduled for tomorrow as well. I will read the early morning reports from the rangers and decide if it worth my time. No point in going up just to spend the day sitting at Hale Pohaku. I may as well get something productive done at headquarters. Thus I pass along a photo from fellow Keck engineer Ean James…

Chaining Up — The Keck crew chaining up on the summit road, image credit: Ean James

Keck in Motion

Keeping the telescopes on-sky every night is the task of the Keck Observatory Operations and Infrastructure Department. A great crew of guys that I am honored to work alongside. This video is dedicated to the guys of the Keck daycrew who make it all possible.

A Bright Glow from Halema’uma’u

It caught everyone’s attention, suddenly the southern sky lit up, a bright glow coming from the direction of our volcano. This occurred about 21:45 last night, we were getting ready to put away the telescopes, ending a great evening at the Mauna Kea Visitor Information Center.

The red glow was unmistakeable, something was happening at Halemau’uma’u. We moved to where we could see the brightly lit plume over the volcano, conversation buzzing with questions, what is going on?

Our guess is that something, most likely a large rockfall, disturbed the lava lake at the bottom of Halema’uma’u crater. The lake, normally crusted over and dark, can be easily disturbed. If something happens to break up the crust, the glow of this very hot lava is surprisingly bright. Bright enough that we were surprised by the show from our vantage point about 30 miles away.

What happened? I will have to read the daily report later today and see if anything out of the ordinary is noted. A nice event, and a treat for the tourists still at the VIS near closing. The glow faded over the next 20-30 minutes. After closing the VIS and beginning my drive back down the mountain, it had faded enough to be barely visible again.

My Canon G11 is not normally a good after dark camera, but given the bright moonlight, and the brighter glow from the volcano, it did fairly well…

Update! Today’s volcano report indicates a series of large rockfalls occurred last night.

Halema'uma'u Glow — The plume at Halema'uma'u lit up at night as seen from the Mauna Kea VIS, 15s exposure with a Canon G11

The Morning Commute

When heading to Waimea this time of year, I am driving right at sunrise. Sometimes you just have to stop and take the photo, or in this case a full set of photos for a panorama, even if I risk being late for the truck to the summit… (Click image to view properly)

Mauna Kea Sunrise Panorama — Sunrise behind Mauna Kea from the Mamalahoa Hwy, near Waimea

Laser Return Photometery

A different use for amateur astrophotography gear.

An amateur CCD camera can do more than take pretty pictures. There is no reason why any decent telescope, however small, and a CCD camera can not be used to do real science, or real engineering in this case.

The goal of the night was to perform proper photometry on the laser returns with independent equipment. We want to quantify the performance of the Keck adaptive optics laser systems. We launch two powerful lasers into the sky, one from each telescope, to allow analysis of the atmospheric distortions through which the telescope is observing. Using the data the system can correct for this atmospheric distortion and create much sharper images of distant stars and galaxies.

The lasers pass through a layer of sodium atoms about 90km (55miles) above the ground. There the 589nm yellow light excites these sodium atoms creating a glowing beacon, what we call the laser return. This return is what we look at to analyze atmospheric distortion. A brighter return allows better data and better performance of the system.

Both the Keck 1 and Keck 2 lasers in operation under the light of a nearly full Moon

Amateur astrophotography gear is perfectly capable of doing this task. A portable telescope, a proper CCD camera, combined with care to acquire calibrated images. All that I needed to add to the setup was a photometric V filter.

It was a perfect night for it, clear, dry and cold. Best of all, there was no wind to bounce the telescope around and chill anyone working outside. The winds are nearly constant atop at 14,000ft peak, calm nights are unusual, I was lucky indeed.

I setup the telescope atop a crust of ice and snow. The snow was convenient as it allowed me to set down gear on a cleaner surface than the gritty volcanic cinder underneath, keeping everything quite a bit cleaner. The altitude and cold made setup and breakdown a slow, laborious process, and added unique difficulties. I had to be very careful moving the heavy gear, so as not to slip on the icy snow. When I went to move the telescope tripod I found it frozen into the snow and cinder! I had to heave hard to break it free.

Continue reading “Laser Return Photometery”

Postcard from the Summit – White Christmas

Regular snowfall has accumulated at the summit. It is patchy, the wind sweeping the snow off the slopes, creating substantial drifts behind buildings and against guardrails. If you want to sled or snowboard, some of the north slopes have a bit of accumulation. Try the small bowl between Keck and Subaru. Need to have a white Christmas in Hawai’i, we can provide this year…

Icy Summit — The Sun setting over an ice and snow covered Pu’u Hau Kea

Light Snow Makes for a Pretty Day

A light snowfall delayed our arrival at the summit this morning. It was really only a few inches, but as usual it drifted into all the wrong places. Thus ice and drifts on the road meant we were waiting for the snowplows to break through.

Waiting was no problem, the Sun was out, creating a very pretty mountain. Olivier and I walked up to Keck from below Subaru as the snowplow cleared the last bit of road. We both had cameras in hand, enjoying the scenery. Not a lot of snow, but a fair amount of ice on any exposed surface. A few days before Christmas it all seemed appropriate.

After a quick job in the AO bench we needed to wait for some adhesive to cure. I ended up joining in with the snow shovel crew, clearing our doors and walkways of small drifts. Shoveling snow is not easy at nearly 14,000ft. Breathing hard, but having fun…

Light Snow — A light snowfall atop the summit of Mauna Kea

Comet Lovejoy in the Daylight

I did attempt to see comet C/2011 W3 Lovejoy in the daylight. I actually tried several times. Once on the morning of the 15th and a couple more times on the morning of the 16th after I heard that the comet had survived perihelion passage. Neither time did I see the comet with an unaided eye.

On the 15th I was not surprised I could not see it. I was in Waimea where there was a lot of low altitude haze and a lot of glare around the Sun. On the 16th I had a much better chance using the clean high altitude air of the summit of Mauna Kea. But still, no comet seen even though it should be just over four degrees from the Sun. This is about the same separation that had allowed me to see comet McNaught in early 2007.

Just to be certain I set the camera on a tripod, placed it just inside the shadow of the Keck 1 dome, and blazed away. Examining the photos on the camera display likewise revealed no trace of the comet, but there were some interesting spots of light.

It was not until I sat down and really analyzed the raw frames that I found something. Using some astronomy software, I calculated the position of the comet when the shots were taken and the field of view of the camera. And lo! There it was, a small spot with a trace of tail. It showed up best in the green channel, and not at all in the blue thanks to Rayleigh scattering in our atmosphere. Stacking nine of ten frames and processing the heck out of the frames does allow you to clearly see the comet…

Comet C/2011 W3 Lovejoy photographed 4° from the Sun on at 19:47UT on the morning of 16Dec2011. Canon 60D and an 85mm lens, stack of nine frames, green channel only.

Postcard from the Summit – Colorful Commute

As winter descends on Mauna Kea, commuting to and from the summit had become… interesting. Fog, snow and ice being regular features of the drive. Winter weather has also brought fantastic cloud formations, all the more interesting as you drive into them. The later dawn and earlier sunset means that our usual arrival and departure times are filled with dramatic light. All elements become part of a spectacular show.