Piecing Together the Tiniest Galaxies

This image is a VLA radio image of DDO 87, one of the LITTLE THINGS galaxies. It shows integrated atomic hydrogen, the ubiquitous gas between the stars. Areas in red show the most concentrated hydrogen, an indicator of where star formation could occur. CREDIT: Lowell Observatory

This ScienceLives article was provided to LiveScience in partnership with the National Science Foundation.

After 17 years of collecting extensive data on a large sample of dwarf galaxies, Deidre Hunter and her LITTLE THINGS team are adding the last piece of the puzzle that will reveal how the tiniest galaxies in the universe form stars. The model for star formation that does so well at explaining star formation in giant spiral galaxies, like our own Milky Way, fails completely for dwarf galaxies. So the LITTLE (Local Irregulars that Trace Luminosity Extremes) THINGS (The HI Nearby Galaxy Survey) team obtained nearly 400 hours of observing time with NSF's Very Large Array (VLA) radio observatory in New Mexico in order to map the atomic hydrogen gas in a sample of 42 dwarf galaxies. The hydrogen gas is the material out of which the star-forming clouds form. The team, which consists of 17 members around the world, is currently calibrating and mapping the VLA data. Those data, together with ultraviolet, optical, and infrared images will help the team to determine what enables these little galaxies to keep forming stars. Read more about the work in Hunter's recent Behind the Scenes feature and read her response to the ScienceLives 10 Questions below.

Name: Deidre Hunter
Age: 56
Institution: Lowell Observatory
Field of Study: Astronomy

What inspired you to choose this field of study?
Just before 7th grade, my friend and I decided that we would become the first women astronauts. This was during the Apollo program and just a few years before the first men stepped on the moon. It was a very exciting time, and many kids from my generation were inspired by this glimpse into space. Aside from the fact that the astronauts then were most often test pilots — something I could never do — I also wear glasses, which is another no-no for astronauts. But our sending people into space made me look beyond the end of my nose. I was fascinated by what was out there, and by high school I had decided to become an astronomer.

What is the best piece of advice you ever received?
It's not exactly advice, but one of the great gifts that my parents gave me was to tell me repeatedly that I could be anything I wanted to be and do anything I wanted to do. I just had to decide on my path. My mother had had a very different experience. Her father told her that women didn't need to go to college because they could learn everything they needed to learn in their mother's kitchen. My mother was determined that my sister and I go to college; that was the one requirement. But she was also determined that we would not have anyone telling us that we couldn't do something.

What was your first scientific experiment as a child?
I feel bad that I don't remember, although I do remember a wonderful microscope that I had as a child and the telescope I built in high school. But as a parent, I see that every child is a natural born scientist. Kids start experimenting and exploring before they can even turn over, and once they are mobile, the experimenting just accelerates. In fact it is our job as parents to protect them from their experiments — the peas up the nose, the rocks in the ears, and everything in the world in the mouth.

What is your favorite thing about being a researcher?
I love figuring out things about the universe that no one knew before. It is like putting a puzzle together. Usually the picture comes together very slowly from a lot of work. But I do remember once when I had done an inventory of the stars in a young, but very massive, star cluster in a nearby galaxy, and I knew for a little while what no one else knew — that the proportions of stars, by mass, in this extreme star cluster were just like that in more mundane star-forming regions. It's so satisfying to have figured that out.

What is the most important characteristic a researcher must demonstrate in order to be an effective researcher?
I think perseverance is the most important characteristic. Most often, answering big questions in science takes a lot of very hard work over a long period of time. The idea of "what did you discover today?" just doesn't apply in most of science. It's more like "what did you figure out this decade?" It helps that research is so much fun.

What are the societal benefits of your research?
People have a natural curiosity about our place in the universe. What is going on out there? We all want to know, not just those doing the research.

Who has had the most influence on your thinking as a researcher?
I had a tremendously wonderful Ph.D. thesis advisor — Jay Gallagher. He is always very excited about astronomy, and I love to talk science with him. He was undoubtedly the biggest influence on how I go about doing research and the tools I have for research. Another person is Vera Rubin; I was a post-doc with her. Vera taught me a no-nonsense focus on the science (not the politics). And I also learned that it was OK for a woman — and a woman with a husband and kids — to be passionate about research, that women in my generation owe a tremendous debt of gratitude to those that endured before us, and that we need to help those that come after us. Vera was, and continues to be, truly inspiring.

What about your field or being a researcher do you think would surprise people the most?
I work with 5th-8th grade teachers and their classes in an outreach program. As part of the assessment of our program, we ask the students to fill out a questionnaire before our first visit and one question asks them to draw and describe a scientist. Quite often the scientist is described as a white male, wearing a lab coat, and speaking with an accent, or as the stereotypical mad/crazy scientist. So, I think these kids don't have any idea that scientists are normal people and that they too can become scientists. They also don't realize that scientists have many different ways of doing research. It isn't all done in a laboratory with test tubes.

Most people also think science is driven by "discoveries."  But the bulk of science really evolves slowly with hard work. There are sudden discoveries, but they are rare and they build on a bigger foundation.

If you could only rescue one thing from your burning office or lab, what
would it be?
I would rescue my back-up disk. I would hate to lose all of my hard work.

What music do you play most often in your lab or car?
We almost always listen to whatever CD my daughter wants to play. It can be Spanish children's songs or the Indigo Girls. But recently it has been the Chromatics CD of AstroCappella. This is an a cappella group that sings original songs about astronomy. The key thing with my daughter is that we listen to the same songs over and over and over and over. Fortunately, my husband and I both really like this CD.