Ground-Based Research

Richard Greenberg, on the Miranda plates

For my thesis at MIT I did things that were very similar to the same topics as what inspired me in the first place, orbital resonances of planets and satellites. I continued to work on those kinds of things [at LPL]. There were some plates that Kuiper had taken, photographic plates, down in the basement. He discovered Miranda, one of the moons of Uranus. The discovery plates, and plates that he’d taken over the course of a couple years afterwards—I guess he took them during the forties, probably—those glass plates were still down there.

Ewen Whitaker and I did some careful measurements of the position of Miranda, and we were able to determine some things about its orbit—its eccentricity and the inclination of its orbit. Those proved to be true. That was interesting because that was the early seventies and we were using those plates from the late forties. I guess those plates must be gone now, or in some cardboard box.

Robert McMillan, on astronomers Krzysztof Serkowski and Wieslaw Wisniewski

I first met Krzysztof Serkowski in the 1970s. He was here at LPL doing various things, but he was mostly involved in measuring the polarization of starlight due to interstellar dust. He had built a polarimeter—that’s an instrument for measuring the polarization of light—and was using that in collaboration with Tom Gehrels.

He also wanted to detect planets orbiting other stars, and his thinking on this began quite far back, probably around 1973-ish, when people were first thinking of things to do with what was then called the Large Space Telescope, which eventually became the Hubble Space Telescope. He was working on ideas for doing that with the telescope in space. But then he began to realize that there may be ways to do that with ground-based telescopes, and he started a project called the Radial Velocity Project, to measure variations in the Doppler shift of stars, that would be produced by the planets orbiting them.

This type of measurement would have required at that time an accuracy of measurement, oh, probably three orders of magnitude—at least two orders of magnitude—better then what was typically available with conventional Doppler shift equipment. So he was designing a very exotic instrument that would require a great deal of careful calibration and lots and lots of photons to make these measurements with ground-based telescopes.

I became involved with Serkowski in the 1970s because interstellar polarization work was the topic of my dissertation. When this job opened up at LPL in 1979 that was first focused on the Pioneer-Saturn encounter and then later to help develop this instrument to detect planets, that second part of that job was going to be collaborating with Serkowski, and it seemed to work out very well because I was already known to him. It was a good combination.

Kris Serkowski had an interesting life. He grew up in Poland during the Second World War and the Cold War, and escaped from Poland and came over to the United States to do astronomy. First I think he was at Lowell Observatory in Flagstaff and later here at LPL. Very nice man, very personable, always very happy and cheerful and so on, but in the 1970s he came down with Amylotrophic Lateral Sclerosis, Lou Gehrig’s Disease, which is a progressively crippling disease and eventually fatal.

By the time I arrived in 1979 he was already half-crippled, and really couldn’t come to the Lab anymore. He had to basically work from his bed at home. We would go to his home and meet in his bedroom and discuss things and come back and so on. So he wasn’t really able to participate much and it was very sad. He died in 1981.

At that time I was just starting to try and get more money for that Radial Velocity Doppler shift program because at the time that it was handed over to me, in 1980, the money was gone, the equipment didn’t work, and its people had left. I had to restart that project from scratch. I got money from the National Science Foundation and also from NASA to run this project. We redesigned the instrument from scratch, wrote all the new software, put it on a telescope, and actually conducted observations for quite a number of years.

It was successful in that we were the first to publish radial velocity measurements of stars better than 20 meters per second accuracy, a really big jump. We also discovered pulsations in Arcturus, a different, new type of pulsations that had never been seen before in any other stars but the Sun. We also discovered the longest period of a spectroscopic binary.

I think it was a very successful program but it suffered from what we call photon starvation. It required vast amounts of light to work effectively, and due to various constraints here in this institution, in the University of Arizona, large telescope time just wasn’t available for a project like this. So we had to use a very small telescope. I don’t feel bad about not having discovered planets, because I think we did a lot more with the limited resources that we had, than anybody else probably would’ve even attempted to do. I think we carried out Krzysztof’s wishes to the extent possible. At least his instrument did see starlight, and it did make measurements. It proved the measurement concept and achieved the desired accuracy. I feel proud of that, and it vindicates his original goal.

Wieslaw Wisniewski is the other Polish astronomer. I met him in 1977 when I was coming out to Arizona from Huntsville to observe with the 60-inch telescope on Mt. Lemmon, which was then being run as a light-bucket, relatively inexpensive telescope doing photometry and spectroscopy of single stars. He was assigned to help the observers who came out to use that telescope from other institutions.

He had worked with the late Harold Johnson, and helped developed the UBVRI alphabet soup photometric system back in the sixties and seventies. He was a very dedicated person, and had a lot of difficult experiences during the Second World War in Poland, and again had managed to get out of the country during the Cold War with his family. He was a great companion, a very personable guy, fun to work with, very energetic and dedicated. He died in 1994; it was February ’94, very suddenly. He just didn’t wake up one morning. It was a big shock to us, because I think he was pretty young, he was only about 62. I took over his research project. I just happened to be at the right place at the right time, and I was available so I picked up his work. I helped, with assistance from other collaborators at other institutions, to get all his data published.

I just wanted to mention those two guys, two exceptionally dedicated and highly motivated, very energetic astronomers, of the old school, who I define as astronomers who personally went to the telescope and spent all night with it. In fact in those days it was all night with the telescope out in the open in the dome, no control room, just standing on a platform all night running the equipment. That’s the kind of observing that I did as a graduate student.