For pre-career, I'll just say I was born in New Jersey, grew up in Connecticut and New Jersey and went off to college with as much of a clue about my future as anyone.
HI-res image is here.
In some sense my science career started at Dartmouth College (I'm class of 1978) where I did a senior thesis with John Walsh in the Physics department on the theory of generating high frequency radio waves using a free electron laser. Here I am 40 years later using those same radio waves to capture first image of a black hole. I don't have words for how weird that is.
I left Dartmouth to pursue a PhD in Physics at MIT (with Prof. Bruno Coppi), and I never left. The original plan was to continue with plasma physics in pursuit of fusion energy, but the US seriously curtailed that program before I got my degree…so I switched to space plasma physics and joined the research staff at MIT in what was then called the Center for Space Research with Tom Chang. I spent the better part of the next decade working to understand the Earth's local space environment: i.e. the Earth's ionosphere, magnetosphere and the Sun's heliosphere.
That was followed by an accidental shift into astronomy (due to changing funding priorities at the Air Force Office of Scientific Research); I moved from theory and analysis of data to generating it. That came about largely due to my computer skills which got a good head start at Dartmouth during the Kemeny era. I shifted to work with George Ricker in his CCD lab, and worked on the first CCD semiconductor imaging-spectrometer instrument (SIS), which was flown on the Japan-US ASCA satellite and I made a start on developing the version of the instrument (ACIS) that is still operating on the Chandra Observatory. However, I was needed for other work, so I spent a decade or so with the HETE satellites (HETE-1, killed by a Pegasus XL [Orbital Sciences Corporation] launch failure, and HETE-2, which was slightly modified and successfully launched). HETE-2 ultimately solved the origin question for long gamma-ray bursts. (The short gamma-ray bursts were also studied, and finally put to bed recently by the LIGO-VIRGO result.)
Before HETE-2 was abandoned, we worked out how to use it for exoplanet searches (NASA declined our HETE-S proposal), which planted the seeds (for several proposal rounds with NASA) for the design of the recently launched TESS mission. However (funding realities again), I wandered back to the helisophere to work for a few years building the science operations software with Nathan Schwadron (now at UNH) for the IBEX mission which had an ambitious plan to map the heliosphere in energetic neutrals. That mission is still running, but it takes a solar cycle (about 11 years) to get full coverage of the Sun, and I was open to something new well before that.
As I was thinking about "what next", I learned of the effort that eventually became the Event Horizon Telescope (EHT) and later Collaboration (EHTC), and figured that "taking a picture of a black hole" was cool and certainly easier to explain to my friends than anything else I'd worked on. So I shifted from the MIT campus to the MIT Haystack Observatory (about 35 miles outside Boston) to work on the project let by Shep Doeleman (now at Harvard CfA). At that point, a demonstration with a few radio observatories had been made to suggest that there was something to see, and I was hooked. Not being explicitly trained as a radio astronomer, my role was much larger on the technical side of things (computer skills and instrumentation). (Although at this point, I guess I qualify as a Radio Astronomer.) In order to make this work (i.e. capture the data needed to make an image), we needed more observatories (a dozen are considered by some to be sufficient to make an image with confidence) and more bandwidth (to increase sensitivity) as the early efforts had proven challenging.
The technique used is called Very Long Baseline Interferometry (VLBI). It involves simultaneously recording the radio signals observed at multiple observatories making a common observation of a target. While it has been used for 50 years now in a number of observing arrays, the EHT effort has pushed the recording rate from 2 Gbps (those first efforts in use with Mark5C recorders when I came to Haystack) to a current 64 Gbps (what we are now working with). I was a key player in developing this generation of recording technology (Mark6) as well as the digital back ends (the hardware that converts the received signals into the bits that are to be recorded) used by the EHT. At the same time, the world's best high-frequency radio observatory, ALMA (in Chile) was coming online (it officially opened in 2013) and I played a major role in the effort (the international ALMA Phasing Project, or APP for short) to adapt ALMA for use with VLBI. ALMA has two interferometers: one (using the so-called BaseLine correlator) with up to 50 12m dishes offers the largest collecting area and resolutions, and a second 7m array (ACA for ALMA compact array)with a larger field of view. These may operate in parallel. The work of the APP was to install the hardware and software to allow ALMA to participate in VLBI arrays. The software involves working out the phase relationships of the signals so that they may be co-added to form a signal that is the equivalent of a 70m dish. Since ALMA is located on the Chajnantur plateau in Northern Chile with excellent observing conditions this makes it the most sensitve element of the EHT. This work placed me in a key supporting role whenever VLBI observations are made at ALMA.
The EHT Collaboration has grown dramatically in the past few years, and there are now several working groups handling the various parts of the processing and analyses, paper writing, &c. While I participate in many of these areas, I've necessarily kept myself focussed on the front end of things (i.e. observation through correlation) while I try to find time to work on the next thing. For me that is to return to my roots on a pair of CubeSat missions (AERO and VISTA) which plan to demonstrate a novel Vector Sensor technology which we plan to use to study plasma waves in the ionosphere.