Sunday, March 22, 2015

Visiting Pu‘u Huluhulu

Back at the beginning of the month I took a trip up Saddle Road to Pu‘u Huluhulu in order to pick up some cinder for use in my comet-making presentation. Pu‘u Huluhulu is a cinder cone at the base of Mauna Kea, on the Saddle region between it and Mauna Loa (its name means, roughly, “hairy cinder cone” due to the trees growing on it, which contrast with the barren lava fields all around). Here's a shot of me at what I've read used to be a cinder quarry on the west side of the pu‘u.

 The day was really overcast and intermittently rainy, so there was a lot of moisture condensed on the foliage. (The white patch behind my head in the picture is actually a bunch of tiny hailstones, which must have happened pretty shortly before I got there.)

Many of the trees that cover Pu‘u Huluhulu (and give it its name) have this really neat looking lichen growing on them. I got some interesting pictures of it with a low depth-of-field:

At the top of the cinder cone is a flat patch, from where you can look out across the Saddle region. This picture looks towards Mauna Kea – if you enlarge it you can see the Mauna Kea access road winding its way up near the center. Fifteen minutes after that picture was taken the clouds descended to completely block that view.

Pu‘u Huluhulu isn't a very large cinder cone, and after half an hour I'd traipsed over most of it and gotten enough pictures to satisfy the artistic urge (most of them weren't really interesting enough to show). It's a pleasant little hike if you ever get the chance – despite being nearly a mile in elevation, it's short enough to keep you from getting too winded while hiking it. A hui hou!

Monday, March 9, 2015

Making a Comet

This past week I took part in Journey through the Universe for the second time. Journey through the Universe is an annual event, running for the past eleven years, where astronomers and engineers from the various observatories on Mauna Kea go into classrooms and give talks to the students there. Most of the time these talks include some sort of physical demonstration or hands-on activity. This year I talked about comets, and as part of my talk I created a miniature comet.

Comets are basically, in the immortal words of Fred Whipple, “dirty snowballs.” They are composed of varying amounts of rock, dust, and various ices such as water, carbon dioxide, and ammonia. In preparation for my presentation I did a few test runs of the comet-making recipe I found, including two at work which proved quite popular with my coworkers. I took some pictures of the process (though in poor light, unfortunately) and thought I'd share them here.

We start with a plastic garbage bag inside a large plastic mixing bowl. (When dealing with dry ice, you really want to keep it away from metal as the extremely fast cooling of the metal causes it to emit nails-on-a-chalkboard-level screeches.)

Next, we add some dirt and stir it in.

Then, we add a dash of ammonia and some corn syrup, to represent the assorted organic molecules detected in comets. Organic, in this context, is used in the chemistry sense, meaning “a molecule containing carbon.”

Now, we crush up two cups of dry ice by pounding it with a meat tenderizer, add it to the dirty water, and stir vigorously. This produces an impressive amount of fog, making it hard to see what's happening, but you can feel the ice start to freeze up pretty quickly.

When it's mostly frozen, you can pick up the bag and form the comet like a snowball (something I have basically zero experience doing, I should note). When that's done, we've got a comet!

(Man, that light is poor.)

I don't usually take pictures of myself, so this actually took quite a bit of practice, and I got a bunch of melting dirty comet-water on my hand and a cramp in my leg in the process. Here's a close-up look at the comet:

This comet may actually be the best one I've made so far. I initially thought some of the chunks of dry ice were too big, but thinking about it now I think that may actually be a good representation of real comets. After making the comet I stuck it in a pan in front of me on my computer desk and watched it as it melted over the course of a few hours. This last picture was taken about half an hour after making the comet, and show pits where the water ice froze around some dry ice which has now melted, leaving a pitted surface.

This is quite a fun project to do. The part where you mix the dry ice and water is especially visually impressive, and quite popular with bystanders. You'll most likely have dry ice leftover, too, so you can have more fun with it after the fascination of watching a comet melt has worn off. A hui hou!

Monday, March 2, 2015


Yesterday, February 28th, marked my last day as an employee of the Joint Astronomy Centre. Come today I've been officially terminated from my position there and become an official employee of the East Asian Observatory. It's somewhat of an historic occasion; it marks only the second time a world-class observatory has been transferred from one owner to another.

The first was UKIRT back in October, but that involved only five staff members and transfer to two organizations that have both been around for a while (the University of Arizona and Lockheed-Martin). This time there are over thirty of us involved, being transferred to a new organization formally created just last year.

As you might imagine, transferring operations from an organization with over thirty years of history to one with just a few months' worth is a tricky process. We've dealt with all kinds of transfer-related issues in the last few months, and will undoubtedly have more that pop up Monday morning, but the tenacity that led us to stick with the telescope instead of finding different jobs will no doubt see us through. Exciting times, to be sure!

Next week I'm taking part in the Journey through the Universe program again, where I'll being visiting classrooms in Hilo and giving a talk about astronomy. The project I picked this year is quite visually impressive, and I've got some pictures of a test run I did so expect to see those up here pretty soon. A hui hou!