Welcome to the Zeno home page!

Zeno has flown again. We just finished our 14-day stint as part of USMP-3 onboard Columbia, mission STS-75. During the mission we were able to bring you several updates on our progress, almost nearly as it happened. Now that we've landed, we are preserving those updates as a way to inform you about this second mission, and to try to give you some flavor of what it was like to do the experiment.

The objective of the Zeno experiment is to measure the decay rates of critical density fluctuations in a simple fluid (xenon) very near its liquid-vapor critical point using laser light scattering and photon correlation spectroscopy, in the microgravity environment of the Space Shuttle. Such experiments are severely limited on earth by the presence of gravity which causes large density gradients in the sample, which is highly compressible near the critical point.

There were many people who made the Zeno project happen. Collaborating principally with NASA/Lewis Research Center and with Ball Aerospace, the Zeno team at the University of Maryland built a high-precision, laser light-scattering spectrometer, tough enough to withstand launch aboard the Space Shuttle. Central to the instrument was a miniature thermostat, capable of controlling the temperature of the xenon sample to 3 microKelvin (yes: 3 microKelvin).

The Zeno instrument flew its first mission on Columbia, as part of the highly successful USMP-2 mission, on 4-18 March 1994. Highlights of the scientific results from the first Zeno mission are given in the one-year report. Although it is contained in the report, we make available a separate bibliography of Zeno publications.

For a really gorgeous view of Zeno on the USMP-2 payload in Columbia's cargo bay, taken by the crew during the mission, download this file in JPEG format (200 kbytes).

Zeno was developed under the auspices of the Space Experiments Division of NASA/Lewis Research Center, in Cleveland Ohio. Visit their home page to find reports on several other microgravity experiments.

STS-62: The Mission

Look here for an overview and detailed summary of the mission, prepared by Kennedy Space Center.

jns@roissy.umd.edu; created on 20 March, 1995; last modified on 15 March 1996.