Senior Data Scientist
Disciplines: Exoplanet Detection
Degree/Major: Ph.D., Electrical Engineering, Stanford University
My background is in signal processing, and my interests lie in astronomy, astrophysics, and planetary science. I entered the doctoral program in the Electrical Engineering Department at Stanford University in 1983. I joined a research group in the Space, Telecommunications and Radioscience Laboratory (STARLab) that was funded at the time by the NASA Search for Extraterrestrial Intelligence (SETI) program. Detection of narrowband radio signals of intelligent extraterrestrial origin was a perfect signal processing problem for me. My research led to the specification of a Multi-Channel Spectrum Analyzer (MCSA) with 10 MHz bandwidth and 15 million channels. My research group also developed a custom VLSI processor which we named the SETI DSP Engine. This chip was optimized to quickly perform the Discrete Fourier Transforms required of the MCSA design. It was a proud moment for me when years later I ran across a copy of this chip at the National Air and Space Museum in Washington, D.C.
The SETI Institute was founded while I was a doctoral student to increase the research opportunities available from limited SETI funding. Following completion of my degree at Stanford, I joined the SETI Institute in 1988 to implement the prototype MCSA that I had specified as a graduate student. The prototype employed dozens of the custom SETI DSP Engines which had now been fabricated and tested. Late in the year we demonstrated a working prototype to our research sponsors and other friends of SETI. A later revision of this MCSA was ultimately employed in the Project Phoenix SETI search at the Institute.
I left the SETI Institute following the MCSA prototype demonstration to experience life in the for-profit sector. I found that it was not particularly to my liking. I returned to the Stanford STARLab in 1991 to work with a Radio Science research group. Over the following 16 years, I developed and operated science processing pipelines in support of Radio Science investigations associated with a number of NASA and ESA planetary missions: Mars Observer, Magellan, Galileo, Mars Global Surveyor, Mars Express, and New Horizons. The investigations focused on planetary atmospheres, ionospheres, surfaces, and gravity fields. My tenure at Stanford ended following the retirement of my long-time supervisor and the ultimate loss of the Mars Global Surveyor spacecraft.
I rejoined the SETI Institute in 2007 to work on the Kepler Mission. The project involved measuring the brightness of 170,000 stars continuously for four years and searching the stellar light curves for signatures of transiting planets (including Earth-size planets in the habitable zone of Sun-like stars). This was now an opportunity to work on the ultimate signal processing problem! I began my involvement with Kepler as a Senior Scientific Programmer in the Science Operations Center (SOC) at the NASA Ames Research Center and after a few years I became the Lead Scientific Programmer. The SOC was responsible for designing, implementing, operating, maintaining, and documenting the Kepler Science Data Processing Pipeline. The Kepler Mission was fabulously successful and has revolutionized the world of exoplanet science. In recognition of our effort, the Kepler SOC was awarded the NASA Software of the Year Award in 2010.
Kepler focused on a rich star field. Thousands of planets were discovered, and thousands more candidates remain to be confirmed. The Kepler targets were distant by design, however, and not particularly amenable to follow-up investigations. The Transiting Exoplanet Survey Satellite (TESS) was selected for flight by NASA in 2013. TESS represents the next step in the exoplanet mission plan at NASA. Expected to launch in the spring of 2018, TESS will survey the full sky over a period of two years in search of exoplanets transiting the brightest, and hence, nearest stars. The best candidates will be followed up with ground-based observatories to determine their masses. The cream of the crop will be observed with the upcoming James Webb Space Telescope to assess the composition of their atmospheres with emphasis on potential bio-markers.
I am the Lead Data Scientist in the TESS Science Processing Operations Center (SPOC) at NASA Ames Research Center. Our team has spent the past couple of years modifying the Kepler Pipeline in support of TESS. We expect to monitor a minimum of 200,000 stars across the entire sky over the course of the mission and search the light curves for transiting planet signatures. Most stars will be observed for 28 days, but on the order of 6,000 in each hemisphere will be observed for a full year. In the coming years, we hope to detect the signatures of thousands more exoplanets!
- NASA Ames Honor Award (2014)“For excellence in the category of contractor employee.”
- NASA Certificate of Appreciation (2011) "For exceptional contributions and leadership in the development of the Kepler data analysis tools.”
- NASA Software of the Year Award (2010)Group award for Kepler Science Operations Center (SOC) Science Processing Pipeline.
- Stanford University School of Engineering Dean’s Award (1997)“For his major role and contributions to the Mars Global Surveyor Mission and other STARLab projects, for his outstanding technical judgment and acumen, and for his excellent representation to outside sponsors.”