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Dr. Renu Malhotra: pick important problems, and don’t sweat the small stuff!

April 25, 2011

Dr. Renu MalhotraDr. Renu Malhotra is a professor of planetary sciences at the University of Arizona’s Lunar and Planetary Laboratory (LPL). Her research in orbital mechanics has spanned a wide variety of topics, including extra-solar planets and debris disks around stars, the formation and evolution of the Kuiper belt and the asteroid belt, the orbital resonances amongst the moons of the giant planets, and the cratering history of the inner solar system. She has helped revolutionize our understanding of the early history of the solar system using the orbital resonance between Pluto and Neptune to infer large-scale orbital migration of the giant planets and to predict the existence of the “Plutinos” and other small planets in resonance with Neptune. Her most recent publication is in press at the Astrophysical Journal and is titled “Secular resonance sweeping of the main asteroid belt during planet migration” (Minton and Malhotra, 2011). 

Kathryn (Kat) Gardner-Vandy, a graduate student at LPL, interviewed Dr. Malhotra in person for the 51 Women in Planetary Science series:

Tell me about your journey to get where you are today.  How did you first get interested in planetary science?  

My earliest memory of becoming interested in science would be in the 6th or 7th grade.  I was in an all-girls school; we had very good teachers and good labs.  I was good in math and enjoyed math and science.  One of the memories I have from 7th grade was getting a fabulous new textbook for geography.  It made me want to study nature.  Also, around the same time, I got into a conflict with a teacher about how to prove that air has mass. I thought that the proof she advocated was completely wrong and didn’t work.  As punishment for insubordination, I had to stand outside the classroom for a while.   It got me more motivated to study nature.   

Did you then decide to major in a science in college? 

In India, you picked a direction after the 10th grade: science, humanities or business.  In science, there were two streams: physical sciences or biological.  I chose the physical sciences.  At the end of 12th grade, I took a national entrance exam for the five elite engineering institutes (Indian Institute of Technology (IIT)).  It was a very competitive exam, and I just barely got through.  That was significant because the major you got to choose depended on your ranking.  The popular major was computer science and electrical engineering, and I did not have a rank high enough do that.  But thankfully that didn’t matter too much; I wanted to study physics.  Two years into college, my grades were good enough that they offered me a one-time opportunity to switch my major.  I had a lot of pressure from family to switch to computer science, but I stuck with physics and graduated from the IIT with an M.S. in Physics in 1983. 

Tell me about grad school.  Where did you go and how did you decide? 

I applied to grad school in the US.  I wanted to come to the US because of the reputation of its higher education system, but also, in my imagination, the destination was the US because of the notion of being free.  India was not a free country, from my point of view.  At the time, I felt very constrained.  My family’s ambitions for me were either to become a school teacher or perhaps go into the Indian Administrative Service. So, this idea of being free in the freest country on earth was a big dream. 

Where did you end up going to grad school and what did you study?    

I went to Cornell and did my graduate studies in the Physics Department.  I wandered into planetary sciences. My first summer there, I got a project with Mitchell Feigenbaum.  He was not doing your standard physics and is very well known for non-linear dynamics and chaos.  He was great to talk to, and I apparently did something clever enough that he liked it and was very supportive of me.  But he left Cornell two years after I got there, to go to the Rockefeller University.  I didn’t want to move to NYC, so I got in touch with people in Astronomy who studied planetary dynamics, which is the preeminent non-linear dynamical system!  I found an advisor in the Astronomy Department, Stanley Dermott.  I worked on the Uranian satellites which was a rather current topic then in the wake of the Voyager 2 flyby of Uranus in 1986.  The first problem Stan handed me was about the anomalous motion of Miranda, and within a few weeks, I came up with an answer of what was going on with Miranda’s orbit.  I hardly knew anything about orbits at that time. It was all about knowing the equations and getting a feel for where the anomaly was coming from.  Solving that problem got me some attention from the wise people in the field.  I think I was very lucky to get two excellent mentors in grad school: Mitch Feigenbaum who introduced me to non-linear dynamics, and Stan Dermott who introduced me to planetary dynamics.  This was a whole new world, and I just felt like it fit me.  Like a key fitting a key hole: this was my field.  I just loved working with the equations of orbital mechanics.

What next? 

I graduated from Cornell with a Ph. D. in Physics in 1988.  I stayed at Cornell for a year as a postdoc and got married at the end of that year.  My husband took a postdoc in Santa Barbara and I took one in Pasadena at Caltech, and the distance was a big part of our early relationship.  The reason I got the postdoc was that Peter Goldreich visited Cornell, and I had just written the paper about the Uranian satellites.  I think he was taken by the very simple, elegant solution I had produced.  Actually, I had two postdoc offers, one from Caltech, the other from the Canadian Institute for Theoretical Astrophysics (CITA).  Ultimately, I decided to go to Caltech because I wanted to stay in the US.    I found Caltech a very vibrant place.  It was very interactive.  There were lots of conversations in hallways.  At Caltech, I had one foot in Astronomy and one foot in Planetary Science, so I was never short on stimulation. 

How did you find a job after your postdoc? 

After the postdoc at Caltech, I went to the Lunar and Planetary Institute (LPI) from 1991-2000.  I was looking for jobs and got two job offers, one was (again) at CITA and one from LPI.  I think in the end it was again about being in the US.  Also, CITA had a strong group, heavyweights in theoretical astrophysics. My thought was that I would get into projects that were other people’s projects. I would be going with the bandwagon.  I would not be doing my own projects. Going to LPI was a non-standard decision.  None of my mentors understood why I went there.  Nobody saw the logic.  I visited Houston, gave a talk, and liked the people I interacted with there.  I even liked Houston!  It was green and beautiful and had open spaces.  And I thought I’d be my own boss there.  I’d do things that I wanted to do.  It was a bit scary once I got there, to be completely on my own.  I had to figure out my own problems to work on.  But then very quickly things began to happen.  Shortly before I got there, there was the discovery of planets around a pulsar, so there was a lot to do.  It was just fun.  I did some of my best work there.  It was a dream job in some ways: 100% research and fully funded.  Your only responsibility was your science.  Also, the director at the time, David Black, was yet another good, supportive mentor for me.  He hired me and protected my time, and we talked science.  His background was in cosmochemistry but he was interested in orbital mechanics. For me it was “an island” where I could do my science with my own ideas and nobody else’s opinions.  That can work out or it cannot.  But it did work out for me.   

How did you end up at LPL?  Was it your intent to find a faculty position?  

It was accidental.  LPI hosted LPSC, and I was on the programming committee for a couple of years, so I started running into a lot of planetary science people.  I ran into Mike Drake at one of those meetings, and on a message board there was a message about LPL hiring new faculty.  I talked to Mike, just making conversation, and I had just seen this ad.  Mike asked if I was interested and said he hoped that I would apply.  I didn’t know Mike Drake or LPL before that. I sent him an application, got called for an interview and was offered the job.  I learned more about LPL and it was a good place to be. Also, Tucson seemed like a nice place to live.  My husband got interested, too.  He is also an immigrant, not from India but from Russia.  We both had the notion of the freedom of the western frontier.  It sounds childish now, but we both wanted to live in “The West”.      

You mentioned earlier that you have children. When did you have your children, and how did that play into your career? 

I had both my children while in Houston working at LPI.  I had six weeks paid maternity leave, and I had accumulated vacation time to use.  My second child was born at the end of my time at LPI.  I actually put off coming to LPL for a year to have my second child.   I moved to Tucson with a 5-month old, which was challenging, but Mike [Drake] was very supportive.  He allowed me to put off teaching until my second year.  People often say there isn’t a good time to have kids.  I’d like to say that there isn’t a bad time to have kids.  You make it work out.  In fact, I think that grad school would be a great time. You have fewer responsibilities and more flexibility.          

Do you have advice for mothers (and aspiring mothers) on how to manage family and have work/life balance? 

The most, most, most important thing is to have a supportive husband.  Everything else is secondary.  How to manage it?  I’ve just muddled through.  There is no formula.  There is always a new situation that you have to manage.  You shouldn’t sweat the small stuff.  Every difficulty is just a temporary phase.  I live in the moment, and I don’t plan too much.  Difficulties do pass and fade away and you get through them.  Something that I have not done right, I feel, but I think has affected me and could be done better is that you have to understand yourself. Know what your limitations are. What gets you aggravated or happy?  Know your own threshold for pain, especially what gets you down. For example, my threshold for household cleanliness is quite different from my husband’s.  What I wish I had done better was to employ household help.  We have not done that.  I have frustration from it, and I know it gets me down.  I suspect it affects my work.  So, to make life easier, I would say to get household help if you can afford it.  I’ve learned to lower my standards.

What was the hardest thing about transiting from a full-time research position into a faculty position? 

As I mentioned before, Mike allowed me to wait until my second year at LPL to teach because I had just had a baby.  But gosh, was it hard teaching that 2nd year.  I had no experience before that.  Plus they threw me into NATS 101.  It’s a very steep learning curve.  You have to be on your feet all the time.  But it was one of my best experiences. Looking back, I advise new professors that they should not teach these large classes first.  Start with upper division or graduate classes first.  It’s a much more sane way to teach your first time.  It’s not just the number of students, it’s the fact you have non-science majors.  You have to hone your teaching skills for their sake.  In the upper division classes, your teaching skills are secondary.  The students are motivated; they have learning skills already.  First-year students, especially non-science majors, have a lot of issues to deal with.  But for me, looking back, even though it was hard at the time, it taught me how to deal with problem students.  The best thing was how much geology and biology I learned in teaching those classes.  My background in planetary sciences was actually nearly zero.  I came as a physicist.  So that was a great learning experience.

Do you have advice specifically for young scientists? 

Pick important problems!  There are interesting problems everywhere.  You just have to look to find them. For me in grad school, it was Pluto.  It was peculiar, it didn’t fit in.  I don’t know if anyone recognized it as a major issue, but it bothered me, and festered in my mind.  In other words, if you recognize an anomaly in your area, dig into it.  More often than not, you’ll find something interesting.  I’d say that’s been what I spend my time doing: digging into anomalies.  Also, students should work hard.  They need to push themselves.  Doing science is not a 9-5 job.  Especially when you are starting out, it occupies your mind 24/7.  You think about it in the shower.  That’s how you get breakthroughs, and that’s how you make major contributions.  If you find yourself in grad school without having passion for it, you’re in the wrong place.  I’m not saying you have to be passionate 100% of the time.  There will be low periods.  But in your core, you have to know that this is it!          

That advice goes well for advisors, too: make sure to discuss big problems with your students.  What other advice do you have for advisors and mentors? 

The role of the advisor is to pick good problems for students.  Sometimes students pick their own problems.  But more often than not, the advisor identifies good problems and introduces the student to the field.  Advisors should always be an example to their students of what it means to have that life in you about your field, an example of what it means to live science.   

Any final comments? 

I think doing science is probably the most uplifting of human activities.  I can’t think of a better way to spend my life.  And I think it’s great we live in a country and a time when it is affordable.  I suspect that historically it is unprecedented how much science is being supported by the public. I feel very lucky to be in this country. 

Thank you, Renu, and Kat for doing this interview!

Dr. Malhotra is being featured here as one of 51 Women in Planetary Science, a series of interviews with successful women scientists on career choices, sequencing, publishing, review panels, and other tips for success. Questions or suggestions for future interviews (we encourage both senior and junior scientists to volunteer to do interviews!) can be sent to us directly or to our email list, which all planetary science women can join!

5 Comments leave one →
  1. July 20, 2015 9:39 am

    My personal opinion about the origin of the SOLAR SYSTEM, express myself on this topic because I think be a subject with particular scientific interest.

    Regional Solar System at the beginning of their training for thousands of years.

    Mars is only a reference that I use to demonstrate what I believe, which may have been exactly how it happened.

    There is an important factor with regard to the current location of Mars and the Earth in the Solar System.

    At the beginning of the formation of the Solar System, originally these two planets were in their position, current, because at the time of the formation of the Solar System, the inner planets were much closer to the Sun than at present, with the exception of mercury, which today still retains the same original position.

    Mars in your position today dai land which once far-flung this world may have had life. A possibility to be taken seriously.

    I think Mercury existed, at the time possibly this small planet was a moon of Venus. Another issue to be examined in detail, because I think it very likely that.

    The sequence of the planets at this time, it was Venus was in the place where is currently mercury, Earth in the position of Venus, Mars in your position today the Earth.

    This issue must be taken into account, that because the universe is evolving.

    I present this opinion, because with the investigations that are being made with the help of the New Horizon, much of which expose can be confirmed.

    Thank you for expressing your opinion on what I present, for being of particular interest to me.


  2. julie permalink
    April 25, 2011 9:50 pm

    Such a nice interview!!

  3. April 25, 2011 3:38 pm

    *Feels inspired to study*

  4. April 25, 2011 3:16 pm

    Dr. Malhotra, I loved your talk about the outward migration of Neptune at the Great Planet Debate, held at the Johns Hopkins University Applied Physics Lab in August 2008. That was a terrific conference; all the scientists were approachable and eager to talk to anyone interested in the subjects being discussed. Are you still doing any work regarding Pluto? I find that little world extremely fascinating!


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