Career as an Astronomer: Cathy Imhoff
- Grades: 3–5, 6–8, 9–12
The following questions were answered by astronomer Dr. Cathy Imhoff of the Space Telescope Science Institute.
What do you actually do as an astronomer?
I do all kinds of things. One reason I like my job is that I use and program computers, I analyze data, I try to understand how the spacecraft works, and I do some research. I use our satellite, the International Ultraviolet Explorer (IUE for short), to get ultraviolet data on very young stars. I've been working on trying to understand what is going on in these stars for years. I also work for the IUE Observatory — we fly the spacecraft, reduce the data, and help the other astronomers understand and use IUE. So I'm kind of an expert with IUE that other astronomers, who are not as knowledgeable, can talk to and get help from.
Why did you decide to become an astronomer?
I liked nature and science when I was in school. I also liked music, reading, and daydreaming. We didn't study much astronomy in school, but I read all the books (about four) in the high school library about astronomy. I thought about becoming a veterinarian, a doctor, or directing an orchestra. But I really didn't decide to become an astronomer until one night during my first year at college when I got my first look through a big telescope. We were looking at the moon, and with that big telescope it seemed so clear and close that I could walk around in the craters.
I also love nature, so that's one reason I chose astronomy. Also, astronomy is a study that allows you to use your imagination. Sometimes I like to sit back and think about what the young stars that I study would really look like if I could visit them. Finally, astronomy (and nature) is very beautiful. You have probably seen pictures of galaxies and stars that are spectacular. Sometimes we scientists get lost in our facts and figures and forget how beautiful the universe is. Then I remember the night that I got to look through a really big telescope at Kitt Peak Observatory. I saw the dim white star in the center of the Ring Nebula with my own eyes, and could see the misty-looking gas that surrounds it. I looked at the great globular cluster in Hercules, which contains thousands of stars. I could pick out the red "giant" stars with my own eyes. I guess that's why I became an astronomer!
How did you get interested in astronomy?
When I was in school — probably about your age — I was interested in all kinds of science things. I collected rocks, put together models of rockets and models of human and horse anatomy, and read a lot of books. Even in high school, though, there weren't many books on astronomy but I read all the ones in our school library (this was in the mid-60s). Also when I was growing up, the first trips were made into space. I remember Sputnik, the first rocket into orbit, in 1957. It was launched by the Soviet Union. A little later, the U.S. launched Explorer I. I remember watching for the Echo satellite in the backyard with my dad. Echo was an early satellite that was basically a huge, shiny balloon. Just after sunset you could look up and see it moving slowly across the sky. Later came the first men in space. The first was Yuri Gagarin, a Russian. Soon there were the Americans — Shepard, Glenn, Cooper — I was in college when men first walked on the moon. But I didn't decide to become an astronomer until I was in college. Before that I was heavily involved in music and thought I was going to study that. I changed my mind in my senior year of high school. When I went to college I didn't know what I wanted to do. Then one night I visited the observatory on campus, and looked through a big telescope at the moon. It looked like you could walk around in the craters! It was beautiful! I guess I remembered then how much I had liked astronomy and, well, here I am.
What interests you the most about astronomy? What areas have you studied in the greatest depth?
I like nature in general. Astronomy is cool because it allows us to ask questions about EVERYTHING. I admit I also like studying a part of nature that people haven't messed up yet with pollution or destruction of habitat. OK, I'll ignore the space probes that we left on the moon, Mars, and Venus, even though they are space junk now!
I am most interested in the youngest stars. I study how they are born and how they change as young stars on their way to becoming "adult" stars like our sun. The stars I study the most are called the T Tauri stars — they are like the sun when it was only a few million years old (that's young! Our sun is five billion years old!).
What do you like best about being an astronomer?
I had to think about this a long time. But I think the best thing is being able to share what I have learned about the universe with others and enjoy their enthusiasm and amazement!
How much schooling does it take to be an astronomer?
Anyone can be an amateur astronomer. All you need is a telescope or binoculars! Or maybe just your eyes! It takes a lot of studying, however, to be a professional astronomer. By "professional," I mean someone who does research, publishes in the professional journals, teaches at a university, and so on. First you must go through four years of college to get your B.S. degree. Most astronomers these days get a degree in physics, plus lots of courses in math and astronomy. Then you go to graduate school. Most astronomy departments that can award a Ph.D. are at fairly big universities. It usually takes around six years of graduate school. It takes about 10 years in school. It sounds like a lot of work, but if you like it then it doesn't matter!
Have you made any discoveries out in space?
I've made some discoveries about very young stars. Using the IUE satellite (the one I work at), I showed that even very young stars have magnetic fields and "storms" on their surface, just like older stars, only even more intense. The sun has magnetic storms too — have you ever seen sunspots?
Do you need a telescope to be an astronomer?
No, I started out reading books when I was young. It was very exciting to read about the planets and how the universe might have started, but I didn't have a telescope. If you live where it's pretty dark at night and you can see the sky, you can learn the constellations and how to find the planets and watch for meteors. Also, you can use the computer to find all kinds of neat things, like the great pictures that the Space Telescope takes. When I was a kid, they launched the first satellite into space! I remember my dad taking me outside to watch one of the first satellites, called Echo, go across the sky. It was big and bright and you could watch it zoom across the sky in just a few minutes.
Which planet are you most interested in and why?
Earth! I love nature — Earth would be fascinating even if people didn't live here.
Is it fun to study the planets?
Yes. Planets are not my specialty, but I like to keep up with the latest results if I can. The planets and their moons are all so different from each other. It makes me appreciate our home planet that much more.
Would you want to visit the other planets?
Sure, wouldn't you? I can picture a special tour we could go on. First, a stop on the moon. We'll put on our spacesuits and go exploring. Imagine playing volleyball in low gravity! Then we'll visit Mars. There are lots of places to visit there — the Grand Canyon of Mars, the ice caps, strolling along in the morning in the ice fog. Next we'll orbit Jupiter in our spaceship. We'll use special viewers to examine the dark band where Comet Shoemaker-Levy hit the planet last year. Go ahead — put together the rest of the tour of the solar system! We can go in our imaginations, even if there are no tour ships yet.
Have you seen the sun in a telescope? How?
Yes, very carefully! You know that looking directly at the sun can make black spots in front of your eyes — that's not good. A telescope collects light, so looking at the sun through a telescope could burn your eyes. What we do is use a special filter that lets through only a little bit of the sunlight. We can use a filter that lets us see special things. A filter that lets through just the red light of hydrogen lets us see lots of details on the sun's surface.
Have you been in space?
No, I'll wait until they have regular discount trips to the moon. My friend Ron Parise has been in space twice. He flew on the shuttle for the ASTRO mission. Their second mission was in February. But now he is home looking at the astronomical data that he collected while he was in space.
Have you seen UFOs?
Nope. Once I thought I saw one, but it turned out to be a Russian rocket that fell apart as it came down into Earth's atmosphere and burned up.
How did you get involved in space?
Years ago I studied astronomy at Ohio State University. I was studying very young stars, like our sun but only a few million years old. We got an announcement that NASA was planning a small astronomy satellite to study stars and galaxies in ultraviolet light. I thought that it would be neat to look at my stars in the ultraviolet — no one had ever done that before. So I wrote a proposal to study the stars with this satellite. That is how scientists get to use a satellite — they write a request explaining why this would be a good idea and then NASA chooses the best ones. At the time I knew nothing about space astronomy. I was very happy when my request was accepted by NASA. I got to participate in some discussions about how we were going to use the satellite even before it was launched. After it was launched, I got to visit NASA and observe my stars. I did the research and wrote papers about what I found.
Later, when I was looking for a job, I found out that they needed a staff astronomer to help run the satellite. I applied for the job and — 14 years later — I'm still here and working with this satellite! The name of the satellite is the International Ultraviolet Explorer (IUE for short). It is sort of a little brother (although older) to the Hubble Space Telescope.
How do you become an astronomer?
There are only a few thousand professional astronomers in the U.S. Many are professors at colleges and universities. They teach astronomy courses and usually do research. Others work at NASA or, like me, with companies that work with NASA, or at the National Observatories. Nearly all professional astronomers have a Ph.D. This normally requires two years of astronomy courses, doing research projects, and then two to three years doing a doctoral dissertation, which is a major research project. The training is roughly comparable to what a medical doctor goes through. Of course you don't have to go this far to enjoy astronomy!
There are many amateurs and others who just enjoy space and astronomy on their own. To anyone who is planning to go to college, whether they study astronomy or not, I recommend getting a broad, solid education. Study at least one foreign language. If you are majoring in a science area, don't neglect other areas. Every scientist must be able to write effectively, read tons of technical papers, present reports, give speeches, and communicate with other scientists from all over the world. Finally, I should mention that the job market in astronomy is pretty bad. The kind of work we do is "pure research," which means it doesn't help put bread on the table or build better planes. With problems in government funding, there aren't many job openings. This has been true pretty much since before I got my Ph.D. — back in 1976!
Some of you may be interested in astronomy and astronomy education materials. Here is a great resource, the Astronomical Society of the Pacific. The ASP is for amateur and professional astronomers and anyone interested in astronomy, especially teachers. They have several education-related projects. They also have a catalog of all kinds of astronomy-related stuff (slides, videos, books), much of which is useful in the classroom. For instance, you can get a project STAR build-it-yourself telescope with tube and lens. Also there is a free newsletter for teachers. They are at:
Astronomical Society of the Pacific 390 Ashton Avenue San Francisco, CA 94112 (415) 337-1100
What is the hardest thing about being an astronomer?
I think that hardest part for me and for most astronomers is having to keep asking for money so we can do research. In order to get the money to visit observatories, pay students to help reduce the data, publish papers, buy and use computers, etc. astronomers frequently have to write proposals. These are requests, sometimes rather lengthy, explaining what science we would like to do, how we want to do it, how much it will cost, and so on. These proposals are competitive — there is only so much money, so only the best proposals will get funding. Many of us write several proposals a year. It is no fun, and it takes away from our time to actually do the science!
Did you ever have a hard time learning and want to give up on your goals?
Yes, there were some things that I found to be hard. My background is mathematics, but I took a number of physics courses. I found some of the physics courses hard — I can always understand the principles but I had a hard time applying them to problem sets (does this sound familiar?). But I kept trying, and I think that my professors understood that. So my grades in a couple of courses were nothing to brag about but I struggled through anyway.
When I was about halfway through getting my Ph.D., the situation with jobs in astronomy got really bad (it is still pretty bad). I wondered if I was working really hard, living on very little money, and spending the best years of my life so I could get my Ph.D. and then end up unemployed. I thought about other careers. I would like to be an archaeologist, but I would have to start all over AND there aren't many jobs in that either! So I decided to just keep going no matter what. My first couple of jobs weren't great, but they were jobs. Then I came to the IUE Observatory and I've been very happy. I have never regretted my decision to keep going, even though sometimes things were rough.
Is it fun looking at stars in a telescope?
Yes!! My first telescope was a 3-inch Edmund Scientific telescope. I could see a lot from my backyard in Ohio. I especially liked to use it to project an image of the sun and look at the sunspots and any other features on the sun's surface that I could pick out.
I think the best night I ever had looking through a telescope was using the 90-inch telescope at the University of Arizona. The scientific equipment had broken down, so we just went stargazing. I saw the Ring Nebula in Lyra and the globular cluster in Hercules — they were amazing! I could see even the faintest stars and the colors of the nebula and the stars. Usually when you look through the telescope it doesn't look like the photographs, but this time it did!
What is the power source for your satellite, and how much energy does it use?
You asked about the power source of my satellite, the IUE. It uses solar arrays. It is so far from the earth, about 25,000 miles, that it is in the sunlight almost all the time, so the solar arrays work great. Twice a year it goes into Earth's shadow. During that time we use two batteries on board the satellite to keep it running until it goes into the sunlight again. I bet you can't guess how much energy we use to run the satellite. Only 140 watts! That's about the same as a bright light bulb!
Does Orion equipment help you when you're looking up at the stars that are real far from Earth?
Most of the equipment that I use is specially built for professional astronomers. Right now I use our NASA satellite, the International Ultraviolet Explorer, to get data on stars. I have also used the big telescopes at Kitt Peak National Observatory. Some of my friends use the Hubble Space Telescope, radio telescopes, and infrared telescopes. So sorry, no Orion equipment.
The newest telescopes use something called "adaptive optics." This is a way for the telescope to adjust for the blurring by the air in our atmosphere so that we can see clearer pictures of the sky, without going into space.