Astronomer of the Month: Mark Dickinson

Each month we will highlight a member of the CANDELS team by presenting an interview introducing them and what it's like to be an astronomer. This month's Astronomer is Mark Dickinson.

Tell us a little about yourself!

I'm Mark Dickinson, and I'm an Associate Astronomer at the National Optical Astronomy Observatory (NOAO) in Tucson, Arizona. I studied astronomy as an undergraduate at Princeton, then did my Ph.D. at UC Berkeley. After that, I was in Baltimore for 10 years at the Space Telescope Science Institute (STScI) and the Johns Hopkins University, first as a postdoctoral fellow and then on the STScI scientific staff, before I moved to NOAO in 2004.   When I first arrived in Baltimore, I shared an office with Harry Ferguson (now CANDELS co-PI), who was then also a postdoc at STScI. Bob Williams, then the director of the Institute, tapped us to help with the implementation of the original Hubble Deep Field (North) observing program. The HDF-North begat GOODS, which begat CANDELS, and so here we are...

What is your specific area of research? What is your role within the CANDELS team? 

I work mainly on the star formation histories of early galaxies - the way in which they formed stars and grew during the early phases of cosmic history, when the universe and the galaxies within it were young. When I started working in astronomy, we had almost no direct knowledge of galaxy evolution during the first half of cosmic history - the only evidence came from interpreting the fossil record of stars within present-day galaxies like the Milky Way. It's been an amazing transformation, driven by the technologies of new telescopes and instrumentation, and by clever observing techniques, which have led us to discover thousands of galaxies in the early universe, back to the era when the universe was less than 10% of its present age. This lets us make direct measurements of early galaxy formation and evolution - truly an opportunity to climb into the Way-back Machine and revisit the early days when the Universe and its galaxies were young, and directly measure how they were born and grew.   

I was involved in several of the major early multiwavelength surveys that led to the development of the CANDELS program, and am now the principle investigator for new observations of the CANDELS fields at far-infrared wavelengths using the Herschel Space Observatory - the largest telescope ever flown in space, which measures the energy from star formation and supermassive black holes at the centers of galaxies, energy that is often absorbed by dust and re-emitted at infrared wavelengths where we cannot measure it with ground-based telescopes. This project reveals the "hidden" side of galaxy formation - hidden by dust, and largely invisible to optical telescopes like Hubble, but which is a key element of galaxy growth over cosmic time.

 

What made you want to become an astronomer? At what age did you know you were interested in astronomy? 

I remember becoming interested in astronomy in elementary school - I loved reading articles in National Geographic and other magazines about the planets and stars, and I remember seeing Comet Bennett, which was very bright in the sky early in 1970.  My parents took me out at night to a hillside in Connecticut, where I grew up, and I was just dazzled by this huge, strange thing in the sky. I can't say that I knew I would be an astronomer then, but I never lost my interest after that.
 

What obstacles have you encountered on your path to becoming an astronomer and how did you overcome them? 

 

I've been incredibly fortunate, particularly with my education - I had every opportunity to dream and to learn, and nobody ever told me to stop dreaming and do something useful. If I had obstacles, they were mainly barriers of my own making - occasional laziness and lack of focus - but astronomy is a field that can reward mental wandering which (occasionally) leads to new inspiration.

Who has been your biggest scientific role model and why? 

That's hard to say, but I have to give credit to my Ph.D. thesis advisor, Professor Hyron Spinrad from U.C. Berkeley. Hy worked in many different areas of astronomy in his career, from stars to Mars to the most distant galaxies, but he was clearly driven by the fun of discovery - by the opportunity to see and find something new that had never been seen before. And, in the particular area of galaxy evolution, by the thrill of the chase - the wish to find the most distant, most exotic objects in the early universe.

What is it like to be an astronomer? What is your favorite aspect? 

I think I like the mix of planning and serendipity: you have to have a research plan, a goal for your projects, but the best part is when unexpected discoveries happen - when you find something you weren't looking for. That's when it all gets really interesting.

What motivates you in your research? 

Coffee. Oh, and the expansion of the universe, which is pretty cool if you think about it.

What is your favorite astronomical facility? (This could include telescopes or super computers, for example) 

I have a deep fondness for the 4-meter diameter Mayall telescope at the Kitt Peak National Observatory. OK, I work at the National Optical Astronomy Observatory, which operates the telescopes at Kitt Peak (and also at Cerro Tololo in Chile). So maybe I'm biased, although ironically I observed at the Kitt Peak 4-meter *much* more often when I was a student and postdoctoral fellow than I do now since I came to work at NOAO. But still I really love that telescope - I got my training as an astronomer there and at the 3-meter Shane telescope at Lick Observatory, but the Kitt Peak 4-meter was really where I struck out on my own for the first time. Unfortunately now budget reductions at the National Science Foundation are threatening future continued operations at Kitt Peak, but there is still hope for a new future at the telescope with a giant new spectrograph funded by the Department of Energy to uncover the secrets of Dark Energy, the inexplicably strange phenomenon that has been discovered in the last ten years or so and which is apparently causing the expansion of the universe to accelerate.

Where do you see yourself in the future? What are your career aspirations? 

Astronomy has become a world-wide collaboration - astronomers work in international teams with colleagues from around the globe. I see myself continuing to travel world-wide to work with collaborators on exciting projects....I just wish that the economy seats in airlines didn't keep getting squeezed closer and closer together...
 

If you could have any astronomy related wish, what would it be? 

 

To have at least one good new idea for research every year.

What is your favorite, most mind-boggling astronomy fact? 

That the universe has a finite age, about 13.7 billion years, but is also infinite and (apparently) will expand at an accelerating rate forever.

 

Is there anything else you would like for the public to know about you or astronomy in general? 

Astronomy is an amazing science concerning a universe whose scale is vastly beyond anything in the realm of daily human experience - and yet, as humans we can actually take significant steps toward figuring it all out. We're learning things now that we hadn't even begun to imagine when I was a student, and that's not *that* long ago. And this process of discovery is a very human endeavor - we learn these things by working together with our colleagues and friends (sometimes our colleagues are our friends). Amazing.