Booster Test

Ever since learning that the space shuttle booster motors were manufactured and tested at ATK in Promontory Utah — not too far from where I live — I wanted to see one of the tests. I didn’t manage to do that before the shuttle program was shut down, but today I got to see something better: a test of an SLS booster, which is about 25% more powerful than an STS booster and more than twice as powerful as one of the big F-1 engines from the Saturn V.

Here’s a close-up video. On the other hand, this one shows what the test was like from the viewing area, in particular the 8 seconds it took the noise to reach us. The sound was very impressive, with enough low-frequency power to make my clothing vibrate noticeably, but it was not anywhere close to painfully loud. The flame was, however, painfully bright to look at. The nozzle was being vectored around during the test (I hadn’t realized that the solid rockets participate in guidance) but that wasn’t easy to see from a distance.

NASA socials give some inside access to people like me (and you, if you live in the USA and want to sign up next time) who have no official connection to the space program. Yesterday we got to tour the plant where the boosters are made. It was great to learn about techniques for mixing, casting, and curing huge amounts of propellant without getting air bubbles or other imperfections into the mix and without endangering workers. The buildings in this part of ATK have escape slides from all levels and are surrounded by big earthworks to deflect potential explosions upwards. It was also really cool to see the hardware for hooking boosters to the main rocket, for vectoring nozzles, and things like that. Alas, we weren’t allowed to take pictures on the tour.

ATK’s rocket garden at sunrise:

And the main event:

Adandoned Mineshaft

Due to my 8-year-old’s obsession with Minecraft, the abandoned mineshafts found in the game are an everyday topic of discussion around the house. He is saving up to buy a pickaxe — no joke. Since we needed a day trip for the long weekend, I thought we’d visit some actual mines in the Silver Island Mountains near the Utah-Nevada border. We followed an old road most of the way up a minor mountain and found the remains of either a processing facility or living quarters, and several mine shafts higher up. One of these apparently goes all the way through the mountain but we didn’t do much more than poke our heads in, since it was difficult to gauge how dangerous it was. This area was mined from the 1870s through the 1930s. Since the pathway connecting the mine shafts with the highest vehicle access was too narrow and steep for vehicles, we were forced to assume that ore was transported downhill using some combination of human and animal power — the level of physical effort implied here seemed to be lost on the 8-year-old, who wants a pickaxe more than ever. We saw a pair of pronghorn antelope — but failed to get decent pictures.

Lamus Peak:

Built-up trail used to move ore downhill through rugged country:

Mine shaft:

Another one, with some nice copper ore right at the entrance:

And a lot of nothing in the distance:

Fall in City Creek Canyon

I’ve lived in Utah for a while now, in three different houses, but always a short walk from City Creek Canyon. This drainage starts right at the edge of downtown SLC and goes 14 miles up into the Wasatch Range. A service road provides easy walking access all year, although the upper parts are not plowed in winter. In summer, bikes are permitted on odd days; on even days there is light car traffic. Bikes are allowed and cars forbidden every day in fall, winter, and spring (though sometimes there are vehicles going to and from the water treatment plant a few miles up the canyon). The lower part of the canyon is heavily walked on nice days, for example by worker bees from downtown on their lunch break. The upper canyon receives light usage and there are many miles of trails and off-trail routes in upper City Creek where you are much more likely to see an elk or a moose than a person. Several of my favorite local mountains, Dude Peak, Burro Peak, Grandview Peak, and Little Black Mountain all overlook the upper canyon. Here are a few pictures from a bike ride the other morning.

Broads Fork

After moving to Utah I decided that regularly spending time in the mountains was one of the best ways to stay sane and healthy. Since I usually can’t make time for an all-day hike, I developed a habit getting up around 5, hiking hard for a couple of hours, and then getting into the office by 8:30 or 9. This was nice while it lasted but had to stop once I had kids. However, now that they’re a bit older, I hope to start doing early hikes again, at least occasionally.

One of my favorite trails for a quick hike is Broads Fork, which gains about 2000 feet over 2 miles, ending up at a pretty meadow with a small beaver pond. There never seem to be too many people here; the nearby Lake Blanche trail gets most of the traffic. The Broads Fork trailhead is about a 20 minute drive from the University of Utah or about 25 minutes from downtown SLC.

Cedar Mesa

For years I’d heard people talk about Cedar Mesa, a remote part of southern Utah containing so many Anazazi ruins that it’s basically a huge outdoor museum. Recently my family spent a few days exploring this area. Despite the fact that Cedar Mesa is well-known — it was popularized, in large part, by a book by David Roberts in the 1990s — as far as we could tell nobody was camped within several miles of our campsite off of a high-clearance track near the head of Lime Canyon, seen here in the evening light:

April is a great time to be in the desert but this area is pretty high elevation (6400 feet or almost 2000 m) and it was well below freezing on our first night out. Here the sun is finally starting to warm us up the next morning:

Yep, the kids are wearing their snow pants. Later that morning we visited the Moon House, one of the larger ruins in the area. Although the hike to it is short, the route is circuitous, first dropping over a small pouroff, following a ledge around a corner, and then following a talus slope to the bottom of the canyon, passing between some huge boulders in the bottom of the canyon, climbing most of the way up the other side, and following another ledge behind a big pinnacle. There are good views along the way:

The ruins are impressive:

Life in the desert, though a bit sparse, is often pretty:

The next day we hiked in Natural Bridges National Monument; as you might expect it contains some big natural bridges:

And there were other things to see as well:

Although metates (stone mortars) are a common sight on the Colorado Plateau, something I haven’t seen elsewhere are the manos (grinding stones) since they are so easy to pick up and carry away:

We had great weather in the early part of the trip but got chased home a day early by a rainy night with a forecast for more rain: the roads in this part of the world tend to turn into grease that is impassable even with 4WD when they get wet enough, and we really did not want to get stuck while pulling our tent trailer:

All in all a nice short vacation.

I’m slowly ratcheting down the number of personal blog posts but I will continue to throw in this sort of thing every now and then.

A Few Panoramas

In the early 2000s, decent digital cameras were new and I was obsessed with stitching photos into panoramas. At the time the software sucked and doing a good job was a lot of work. However, I assembled plenty of them and figured out how to get them printed and my house is somewhat littered with panos. In 2013, stitching a good panorama using Photoshop is more or less trivial and paradoxically I’ve largely lost interest. Even so, a recent trip to canyon country resulted in so many good views that I assembled some panoramas for your enjoyment. I’ll just note in passing (now that Utah’s national parks have re-opened, though the government is still shut down) that all of these views are from locations many miles from any kind of park. One of these is from a state highway; the others required more or less serious hikes. If any of my 4400 students are reading this, I hope you will appreciate that I based this trip out of a motel instead of camping so I could respond to your questions at night.

From the top of South Caineville Mesa:

Dirty Devil River from Sam’s Mesa:

Towards the San Rafael Reef from Highway 24:

Looking down on the Mexican Mountain area of the San Rafael Swell:

Partway up a hike to the top of the San Rafael Reef:

Jay

Jay Lepreau died five years ago today; I wanted to share a few thoughts about him.

In spring 2000 I had a year of school left. Sarah had graduated and gotten several job offers; Utah was one of them. This seemed like a bit of an odd choice for us except that Jay flew me out and subsequently offered me a postdoc position once I finished up — the chance to work with Jay and his group was one of the main deciding factors for us to move to Utah.

My friend Alastair, who worked for Jay at the same time I did, talked about “the spotlight.” If the spotlight was shining on you, then you had Jay’s full attention; if not, then you might not be able to get his attention at all. Jay was very intense and spent many nights in the office, where he kept a ratty sleeping bag. Routine tasks such as ordering office furniture were put off literally for years, but on the other hand when papers and grant proposals went out, they had a sense of purpose and vision that I’ve spent an awful lot of time trying to recreate on my own.

The best memories I have of working with Jay are of a handful of times where a two or three hour meeting with him resulted in some substantial change in the direction in my work. In particular, I remember one time we met at a cafe near campus, probably in 2002. I showed up in sort of a confused and frustrated state about some piece of work (I don’t even remember what it was) and we just sat out in the sun on this warm day and talked things out for most of the afternoon. Afterward somehow I was no longer frustrated and confused.

Unfortunately I never managed to go on a desert trip with Jay; this short piece, written by a long-time friend of his, gives a sense of what that would have been like. The last time I saw Jay outside of the hospital was in Spring 2008; he and Caroline came over to my house for dinner, I remember it being a really nice evening.