Wednesday, July 22, 2009

Women in the White City

I was researching a story when I came across a fascinating entry related to the World's Columbian Exposition of 1893. The Exposition was held in Chicago to commemorate the 400th anniversary of Columbus' discovery of America. This is one of those events that I wish I had been around to see in person. I would have gladly joined the 28 million other visitors who came to the Exposition during its six-month run from May to October of 1893. The Exposition was a World's Fair that was meant to celebrate the achievements of mankind since the days of Columbus. It was called The White City because of the white marble-like facade of its so-called Great Buildings. At over 600 acres, the Exposition was larger than Disney World's Magic Kingdom, Hollywood Studios, and Epcot combined.

The Great Buildings were designed by a Who's Who of the best male architects in America. All of the buildings, that is, but one. Everything about the Women's Building was left to the Board of Lady Managers who planned, built, and selected all of the exhibitions. Because there were so few women architects at the time, the Board held a competition to identify a woman architect to design the building.

Sophia Hayden (later Bennett), the first female architect to graduate from MIT (in 1890), won the honor. She was 23 years old at the time. She designed a graceful Italian Renaissance villa which was very reminiscent of her thesis project at MIT.

When she won the award in 1891, she was employed as a drawing teacher in the Boston schools because no architectural firm would hire a woman. She was paid approximately a thousand dollars for her design, one tenth the fee paid to male architects.

Her design was hailed for its fine lines but it was also assailed as being obviously the work of a woman. Despite her success with the Women's Building, she retired from architecture following the Exposition as she still could not find suitable employment. She married and lived a quiet life in Massachusetts, dying in 1953.

The Women's Building was instrumental in advancing women's rights on many fronts including women's suffrage. All of the exhibits were deliberately designed by the Board to be non-competitive, although women did compete with men working in their fields in other buildings at the Exposition. The Women's Building was filled with examples of women's work in every field imaginable, selected from submissions from all over the globe. It was certainly the most graphic example up until that time of women capably matching every aspect of the achievements of their male counterparts.

I wonder what might have become of Sophia Hayden had she been recognized as she surely deserved? Times are somewhat better today for women but there is still much more room for women to gain equality with men.

Postscript: The Women's Building, like virtually all of the buildings at the Exposition, was torn down shortly after closing day. The only building to remain in its original location is the Palace of Fine Arts which is now the Chicago Museum of Science and Industry.

Monday, July 20, 2009

Even Apollo Required Mundane Fixes

I wrote in my last blog about the new images of the moon which show the Apollo landing sites and even the astronauts, footprints on the moon. The photos also show the scientific experiments that were placed there to monitor the geophysical makeup of the moon. These experiments were collectively called the Apollo Lunar Surface Experiment Package (or ALSEP). Each Apollo mission carried a set of experiments but the mix of experiments was different on every flight. [The image to the left was from Apollo 16 and you can see the Lunar Rover in the background next to the Lunar Lander.]

I began working for Bendix Aerospace Systems Division in Ann Arbor, Michigan in 1970, right after graduating from the University of Michigan. Bendix was the prime contractor for the ALSEP experiments. The Apollo 11 and 12 missions had already successfully landed on the moon by the time I joined Bendix. Shortly after I started, the Apollo 13 disaster occurred (April, 1970) and it set back subsequent missions by more than a year. I was involved in engineering efforts on all the subsequent Apollo science packages (14 through 17).

A little background about the experiments: ALSEP was designed to be a package of experiments that shared a common communication and power source. The Central Station housed all of the communications electronics and telemetry systems. It is the tall, gold structure in the photo below. The antenna for transmitting data is the pole-like object on top of the Central Station. The gold is actually metal-coated mylar-plastic film and it was used to control the thermal environment inside the Central Station. Keep in mind that the moon in the daytime is over 200 degrees F and it is -200 degrees F at night. That is a tough environment and controlling the temperature in the electronics in all of the experiments was a major challenge.

The little gray, finned object to the left and behind the Central Station is the Radio Thermal Generator or RTG. It is the power source for all of the experiments. Electricity is generated by converting the heat from a Plutonium-238 fuel cartridge inside the RTG. As an aside, one of the Apollo 12 astronauts said that he could feel the heat from the Plutonium cartridge all the way inside his space suit when he was loading the cartridge into the RTG. That's hot (in more ways than one)!

The silver disk-like object in the foreground is actually a lunar seismometer, part of something called the Passive Seismic Experiment or PSE (the program just loved acronyms). It was designed to measure "moonquakes". Actually, you are not looking at the seismometer but at the thermal shroud (think blanket) which covered the seismometer. The instrument was so sensitive that if it had been directly exposed to the lunar day and night, it would have "creaked" due to thermal expansion and contraction. Even with the thermal shroud, it still creaked a little and buggered up the data.

All of the experiments (and there are three more that are out of the picture) were connected to the Central Station by cables. You can just make these out in the photo as copper/gold-colored ribbons in the lunar soil. They really were ribbons, by the way, ribbons that were about three inches wide, each of which carried multiple wires.

By the time I got to Bendix, the system and the experiments had already been designed (the work started in 1966). Bendix was in the process of building the final instrument packages and testing them to make sure they were ready for their missions. As a young engineer, my job was to work on problems that came up from experiences on previous missions. One of those experiences happened on the Apollo 16 mission. Astronaut John Young was deploying some of the experiments when his boot became entangled in one of the flat-ribbon cables. With the bulk of his suit and the changed sensations of lunar gravity, he was completely unaware that he had snagged a cable. When he moved, he accidentally tore the cable out of the experiment (it was an experiment for measuring heat flow) and the experiment was wrecked. Several million dollars gone in an instant. You can see this happen in the movie below if you start watching around the 11:36 mark. (The whole movie tells the story of the Apollo 16 mission. It is worth watching.) [movie from Internet Archive]

I was at work the afternoon that the ALSEP deployment was being broadcast live from the moon. We were all in a conference room watching a television and we could see Young get tangled up in the cable and everyone in the room started yelling at the set as though Young could hear us. There was a palpable gasp that went up from the group when we saw the cable snap. We knew before Young did that it was not going to be repairable. It is just not possible to put a broken cable back together on the surface of the moon.

Not surprisingly, shortly after the mission, orders came down from NASA to look at ways to prevent this from happening again. Despite the best of planning, nobody had really thought about strengthening the cable connections. Each of us has tripped over an extension cord or laptop power cable sometime in our lives. Usually, a plug pops out of its receptacle but sometimes plugs can be damaged or broken. Same here. But there were no plugs to come undone (the cables were hardwired in place). The cable snapped. My job was to design a better cable strain relief that would withstand the impact of a skipping astronaut in full gear. We couldn't change the basic cables so we had to find a way to spread the load out. A combination of well-rounded mounting brackets and reinforcing fiber tapes seemed the best way to get the job done.

But how do you test something like this to know it will work? You can't go to the moon to do it. We rigged up a test system in the lab and enlisted our "test astronaut" to see he could break the cables in a deliberate accident. What you see in the first picture below is the ALSEP package of experiments (a non-flight model) in the form that it is stowed in the Lunar Lander and before it is unpacked. Attached to the front of the package is our redesigned test cable with a heavy lace to put around the test astronaut's leg. Yours Truly is standing with my back to the camera in the stripped shirt.

It didn't seem like a fair test to have the high friction between the bottom of the ALSEP package and the floor of the lab so we put the package on a greased plate to decrease the friction and more closely simulate the friction in the lunar dust.

The next photo shows the test in progress with the astronaut putting his full weight into the cable. Two assistants stood on either side of him to catch him if he fell. You can see the cable snap taut.

The last photo shows me examining the cable stress relief after the test. It worked; the cable was intact and fully functional. This wasn't the only testing but it was the most convincing. We retrofitted all of the cables on the Apollo 17 mission with the new strain reliefs. Of course, the astronauts were now extremely mindful of getting tangled in the cables and nothing untoward happened on that mission.

Complex missions like the Apollo Program were staffed by tens of thousands of engineers doing the same sort of unglamorous, day-to-day jobs like fixing cables. Nothing is perfectly designed the first time. Not every contingency can be planned for. (If you want to see the ultimate example of this, rent the movie Apollo 13). To tell the truth, many days were pretty mundane but I still feel proud of the fact that I was there and had a tiny part in the Apollo missions. We have so few things in life that command the kind of vision that the Apollo Program did. It brought out the best passions in so many people. As Georg Hegel, the German philosopher said, "We may affirm absolutely nothing great in the world that has been accomplished without passion." Apollo proved that to me. I wish there were a comparable challenge to stir the dreams of the next generation.

Postscript: The ALSEP packages went on sending back data until September 30, 1977 when for the reason of budget cuts, the experiments from all the flights were powered off to save costs on the earth-side monitoring station.

P.S.S. Today mark's the 40th anniversary of the first lunar landing on the Apollo 11 mission.

Saturday, July 18, 2009

Return to Apollo

NASA reported this week that for the first time the Apollo Lunar Modules have been able to be visualized from a new satellite named the Lunar Reconnaissance Orbiter (LRO) which arrived in lunar orbit on June 23, 2009. In the image below you can see the the Apollo 14 Lunar Module Base on the right and the scientific experiment package on the left with footprints traversing between the two sites. This is incredible detail for an orbiting imaging satellite.

The images (all the sites except Apollo 12 have been imaged so far), are particularly timely given the 40th anniversary of the first lunar landing coming on July 20th. I can remember being glued to my television set at home that summer day watching the commentary provided by Walter Cronkite. I was saddened to hear that Mr. Cronkite died yesterday at the age of 92. For me, he was the voice of the Apollo lunar missions. The New York Times has a number of video clips of Cronkite on their website including this video of the Apollo 11 Lunar Landing in which he is visibly moved by the landing. We all were.

I didn't know at the time I was watching the first landing that within a year after college graduation, I would be hired by Bendix Aerospace Systems Division which had the prime contract to design and manufacture the Apollo Lunar Surface Experment Package (or ALSEP in the jargon of the day). I worked on experiments that were flown on the later Apollo 14 through 17 missions. Those were exciting times when as a nation we could feel good about some of our accomplishments. The quagmire of Vietnam eventually brought the Apollo missions to a premature conclusion with the cancellation of Apollo flights 18, 19, and 20.

When I think now about how primitive our technology was in the late 1960's, I am all the more impressed with the accomplishments of the NASA team. Despite the subsequent successes on SpaceLab, the Space Shuttle, and the International Space Station, we have not yet surpassed that "one small step" which was taken on a day in July forty years ago.