What does it take to dismantle the deep rooted notion that an interest in science should always lead to engineering. The answer is simple, a love for Physics !

Khyati Malhan, our next pathbreaker, Postdoctoral Researcher & Astronomer at the Department of Physics, Stockholm University, Sweden, researches the long-standing puzzle of how did our Galaxy (the Milky Way) form and what are  its dynamical properties.

Khyati talks to Shyam Krishnamurthy from The Interview Portal about being intrigued by the concepts of Physics that govern the cosmos and taking a giant leap to answer those questions through a PhD in Astrophysics.

For students, in the race to crack entrance exams, never forget to appreciate the beauty of science for what it is, because those experiences might lead you on a path that you never imagined you would take !

Khyati, what can you tell us about yourself? 

I am an astronomer working at the Department of Physics, Stockholm University, Sweden. I work in the field of Galaxy  dynamics and formation, i.e., I address problems such as “How did the Milky Way galaxy form?”, “What is the total mass  and gravitational potential of the Milky Way”, “ What is the nature of the mysterious dark matter and how is it distributed in  the Milky Way?”. I completed my Ph.D. in astrophysics (2015-18) from Observatoire Astronomique de Strasbourg,  France, for which I was awarded the Ph.D. of the year 2018 prize by University of Strasbourg. Quite recently, I was  awarded the prestigious Humboldt Research Fellowship by Alexander von Humboldt Foundation, Germany.  

You may find me on:  



Let’s start from the beginning, from when you were growing up ? 

I was born and raised in New Delhi. Both my parents are ex-Government employees. My mother has an academic background in Mathematics, and during school days she was my Math Guru. My parents impressively struck the perfect work-family life  balance. It is their innate hard working and “never-give-up” attitude that consequently moulded me into a very gritty person (a  value in me that has often been appreciated by my friends and mentors). 

I did my schooling from Green Fields School, Safdarjung Enclave. During this time I took genuine interest both in studies and extracurricular activities. My mantra from the beginning was: while the primary goal of attending school is to enhance  knowledge through subjective classroom teaching, it is equally imperative to also participate in extra-curricular activities as  they are extremely useful in shaping one’s character and personality. For instance, during my school days, I was very keen on participating in public-speaking events, and I enthusiastically took part in numerous English, Sanskrit and Hindi recitation competitions. Little did I know back then that these childhood exposures (though totally unrelated to Astronomy) were  developing me into an eloquent speaker. This skill, that I developed gradually with time, helps me today to deliver scientific  presentations confidently at International conferences, and to also build strong collaborations. Additionally, I was strongly  inclined towards playing basketball, painting, music, watching documentaries and playing video games (I am unsure if I’d  recommend this to millennials). 

Surprising as it may sound, but I was not completely aware about the field of Astronomy even while graduating from school. Though, I was always fond of Mathematics and Science. These two subjects invariably gave me the priceless “Aha!”  moments (goosebumps that I still get when I stumble upon a new finding). By the time I joined XII standard, I had discovered my passion for Physics.  

What did you do for graduation/post graduation? 

I pursued B.Sc. (Hons) in Physics (2010-13 ) from Sri Venkateswara College, University of Delhi, and M.Sc. Physics (also  from University of Delhi, 2013-15). Admittedly, this choice was based on a complex trajectory. I did my PhD in Astronomy  & Astrophysics from The University of Strasbourg 

What prompted you to take up a career in Physics? 

During XI and XII standard, I had joined external coaching institutes to prepare for national level engineering entrance examinations like IIT, AIEE, BITS and IP. Back then, if you had opted for science in high school, then the idea was that “since you have taken Science, you obviously want to do Engineering”. This deep rooted notion was so powerful that it had overtaken me, and not for once did I consider asking myself “What exactly is Engineering?” and “Would I like Engineering as my career?”. I am not very sure whether this notion still exists. 

Meanwhile, I was perpetually enjoying the experience of learning Physics and solving problems. The reason behind this was that I had wonderful Physics teachers both in my school and coaching center. Before I realised, I had become more of a  Physics student than an Engineering student. I was intrigued by the concepts of Physics, and how they governed the cosmos.  

In XII, I scored 88% (87/100 in Physics and 92/100 in Mathematics). I lamented the 13 mark deficit in the subject I loved. It  took me a couple of days, and my dad’s Lemon Chicken, to make peace with it (because when life throws lemons at you, you  quickly make Lemon Chicken out of it!!). In the parallel universe, with regard to Engineering entrance exams, I managed a  terrible score in the IIT exam, secured a decent rank in AIEEE, and was ranked among top 4000 in BITS and IP exams. But, I never applied for any Engineering college counseling sessions because I wanted to pursue Physics. When my father asked me the cliched “So, what’s the plan?” question, I replied with uncertainty, “Is it okay if I pursue further education from  University of Delhi?”. My father boosted my confidence by asking, “Which course are you thinking of?”, and I confidently declared “Physics”.  

During three years of B.Sc., I thoroughly enjoyed exploring various topics in Physics: Mathematical Physics, Classical  Mechanics, Quantum Mechanics, Nuclear Physics, Wave Mechanics, Electricity and Magnetism, etc. Thanks to my lecturers,  I achieved 2nd rank in the University of Delhi South Campus in 2013.  

After passing B.Sc. in 2013, the natural next step for me was to pursue M.Sc. Physics. I decided to do M.Sc. from Delhi University, and their brilliant Physics faculty made me confident about my decision. In 2015, I passed M.Sc. with distinction  (78% aggregate), with specialisation in topics: Quantum field theory, Nonlinear dynamics, Electronics, Particle Physics,  General Theory of relativity and Cosmology.  

How did you end up in such an offbeat, unconventional and uncommon career? 

There were several key drivers for pursuing Astronomy 

In addition to being influenced by my teachers at school and lectures in the college, I was also influenced by the lectures of the physicists Stephen Hawking, Carl Sagan and Brian Green. I used to enjoy watching documentaries on TV channels as well as online. I also used to enjoy reading about the ground breaking discoveries in Astronomy. One credit that I would give myself is that I have always kept myself aware of the opportunities, and have grabbed them crazily without being too picky (as  described below). 

During B.Sc., I also explored some internship opportunities: In 2012, I worked in the Laser lab of Defence Research and  Development Organisation, Delhi for ~2 months, and in 2013, I worked in the Plasma lab of Saha Institute of Nuclear  Physics, Kolkata. With these achievements and hands-on experiences, I started to visualise the field of Physics as a possible  career option. By the end of graduation, I had gained interest in Quantum mechanics and Particle Physics.  

During M.Sc. I obtained the winter school fellowship at Tata Institute of Fundamental Research, Ooty in 2014. Exploring  these internship opportunities is extremely extremely important. This is because (1) these experiences give you real exposure to the field (and there are plenty of such opportunities both in India and abroad), (2) as you advance in your career, such real life experiences outweigh the relevance of exam-scores.  

I gained knowledge about these internships mostly from the University office, but sometimes also  through friends. The application procedure to apply for such internships includes preparation of a “Letter of Motivation”  (where the applicant describes his personal interest in Physics and the sort of research activities they are interested in conducting) and approaching their mentor/teacher to submit a “letter of recommendation” to the research institute. Through these internships, I gained real experience on how research is conducted, how a problem is explored from the very beginning, how  experiments are performed in real life, and how a team of scientists collaborate and agree to pursue a very big problem. I was  amazed by the passion and persistence of these scientists. In these internships, I was searching answers for some very new and interesting questions. One of the motivations behind research is that your contribution to the field is real, i.e., you help in  advancing the field in real time.  

On completion of my M.Sc. Physics, I was offered the position of Asst. Professor by the esteemed Aakash Institute for preparing XI and XII students for Engineering exams (yes, what an irony!). Though I was interested to pursue Ph.D. on a topic related to Particle Physics, I deemed it best to take up the position of Asst. Professor, and postpone the option of doing a Ph.D.. However, destiny had a different plan for me!  

One afternoon, in the summer of 2015, my classmate brought to my knowledge an open Astronomy Ph.D. position in a  French University. The opportunity sounded very appealing, and in an instant I prepared my resume and emailed it to France, to Dr. Rodrigo A. Ibata (Dr. Ibata would eventually become my Ph.D. supervisor, and is now a life-long collaborator). Thereafter, I went to sleep laughing and wondering as to, “what are the odds of receiving a reply from this famous  international astronomer, who probably receives hundreds of emails from opportunists like myself”. To my surprise, within  an hour, I received a reply from Dr. Ibata suggesting a skype interview. I was both thrilled and nervous. We spoke, and he  immediately endorsed me as a Ph.D. candidate. Later that year I started my doctoral studies in Strasbourg, France.  

The topic of my Ph.D. thesis was  “Detection and analysis of stellar streams of the Milky Way”. Briefly, stellar streams are “fossils” of the Galactic formation process. These star structures orbit the Milky Way galaxy and they are extremely powerful tools to understand (1) the  formation history of the Milky Way, and (2) constrain the properties of the mysterious dark matter (a particle that makes up  over 70% of the mass budget of the Universe). During my Ph.D., I build the STREAMFINDER algorithm to find stellar  streams in the Milky Way. This algorithm is mostly coded in C++ and Fortran language. The mission of STREAMFINDER  is to analyse the Gaia dataset (astronomical dataset of our Galaxy) and discover new streams of our Galaxy. This map of stream detections is shown below. Additionally, during my Ph.D., I also undertook analyses of these stream detections to  constrain both the mass and the three-dimensional dark matter distribution in the Milky Way.  

Stellar Streams

How did you plan the steps to get into the career you wanted? Or how did you make a transition to a new career?  Tell us about your career path 

I had a vision for my career – to join the field of academics and become a researcher in the field of Physics, and my methodology was to set short term goals (on the horizon of 2-3 years), and then achieve these goals.  

My mantra has always been, One goal at a time! Whenever I have made an academic decision, I have pursued that goal single-mindedly. I have never thought of myself as extraordinarily intelligent or smart, but I know for a fact that I am  extremely persistent and dedicated in my work.  

During B.Sc., I managed to get into two internship programs: In 2012, I worked in the Laser lab of Defence Research and  Development Organisation, Delhi for ~2 months, and in 2013, I worked in the Plasma lab of Saha Institute of Nuclear Physics, Kolkata.  

During M.Sc. I obtained the winter school fellowship at Tata Institute of Fundamental Research, Ooty 

To pursue a PhD in Astronomy, it is a prerequisite to have degrees of Bachelors and Masters in either Physics or  Astronomy. However, a small fraction of PhD positions are also offered to exceptional students from other fields (e.g.,  those from computer science, mathematics, statistics).  

Undoubtedly, building a network is extremely important! Interact with teachers to communicate your interests and your  career plans, as they will be your best guides while recommending you for higher positions (be it for internships, fellowships,  or PhD). Also, make a group of friends who also share similar interests, and help each other in your common pursuit.  

In sum, and frankly speaking, there is no defined plan for anyone to gain success in their career. It naturally boils down to a hit and trial approach. You aim for 10 different opportunities, and bag 2 out of them. This is a success and one should celebrate it. This means you are on the right path.  

How did you get your first break?  

I believe that my first break was getting a Ph.D. position in 2015 in Strasbourg, France. As already explained, this could not  have happened without my classmate who shared this opportunity with me. Yes, your friends play a huge role in shaping your life, so choose your friends very wisely.  

What were the challenges you faced in your career? How did you address them? 

It was initially quite challenging to pursue PhD in France due to two main reasons: 

Challenge 1:  

For the first time I was away from home and in a new country. It was challenging to adjust to the new and  unfamiliar territory. This initial feeling of unfamiliarity stressed me for sometime, often followed by the feeling of  homesickness. Nevertheless, I kept my patience and this feeling subsided. I started to familiarize myself with the indigenous  crowd and the wonderful French cuisine. I also indulged myself in several cultural activities. These motivational encounters  helped me to firmly seize this opportunity. Instantly, I fell in love with Strasbourg (Gosh, I miss that town!) 

Challenge 2:

My Ph.D. was in astrophysics – a subject in which I had negligible formal experience in. Therefore, I spent the  first trimester of my 3 year PhD program educating myself about this field. I extensively studied lots of books, tried to solve various numerical problems, and worked on Python computer programming. Though this was hard to do all at once, I was starting to equip myself with new skills and tools. My colleagues and PhD supervisor also helped me a lot during the initial  periods when I was struggling. 

Where do you work now? Tell us about your research 

At present, I work as a Postdoctoral Researcher at the Department of Physics, Stockholm University, Sweden.  

My work focuses on (1) understanding the long-standing puzzle of how did our Galaxy (the Milky Way) form and what are  its dynamical properties, and (2) constraining the physical properties of “dark matter” (a mysterious particle that makes up  >75% of the mass budget of the Universe). These are two of the most fundamental problems of astronomy, and they are also  inter-linked. This is because, as per the standard theory of cosmology, dark matter particles are the major cosmic drivers of the Universe, and their physical properties influence the process of galaxy formation. I should also highlight that this growing  field of “Galactic dynamics and formation” is a rather young field (~30 years old) compared to other fields of astronomy.  This makes this field particularly exciting and competitive as there is a lot to explore.  

What are the skills needed to be an Astronomer? 

The skills that are needed for a typical Postdoctoral position in astrophysics:  

> Hard Skills:During my Ph.D., I learnt about the field of astronomy itself (by reading books, scientific papers and interacting with colleagues and seniors), gained working experience in computer programming (in addition to C/C++ language, I also  learnt Python and bash) and numerous astronomical tools. I learnt how to analyse astrophysical datasets to learn about the  dynamics of stars in our galaxy. During doctoral studies, one also naturally learns the skill of writing scientific papers and  proposals. Make sure that you learn this skill of being a very good scientific writer, as this skill decides the chances of your success in the field. This is because the only way for the community to judge you as a researcher is based on the quality of  your published papers.  

> Soft Skills:The values of being patient and persistent are extremely important in the field of research. This is because, as a  researcher, you are expected to stick to a particular problem for a very long time (typically ranging from a couple of months  to a couple of years). This duration of toil is proportional to the complexity of the problem at hand.  

What is a typical day like? What do you love about your job? 

A typical day from the outside seems monotonous, but, in reality, it is not. For instance, if you were to observe me working in my university office, you would see me following a 9am-6pm routine, mostly writing python, bash and C/C++ scripts, and  frequently gazing through some colorful figures on my desktop screen. Quite uneventful, right? But in reality, I (like any other researcher) deal with a slightly different problem on a daily basis. That is, a researcher strives to make progress in a certain direction by solving the next problem that comes his way. This is what research is. Since every day is a new challenge, and  you try to answer a new question, this nature of work also keeps you interested and motivated in research.  

There are several aspects I love about my job. (1) Astronomy provides me with the opportunity to address very interesting  questions about the Universe, and I like to be part of the cutting-edge field of research. (2) The field of research also offers  me independence to pursue problems that I like (typically after Ph.D., a researcher is expected to design and lead their own  research programs). (3) Astronomy also offers the wonderful experience of learning new skills, astronomical tools, and the thrills of analysing the data of stars and galaxies. 

How does your work benefit society?  

Honestly, there is no direct way of gauging how the work of an astronomer benefits society. Indeed, if an astronomer has  discovered a new star that moves with a speed of 1000 km/s, or if he has discovered the most massive galaxy in the  universe, how can these discoveries possibly help the underprivileged, uneducated and unemployed of our society? But  history provides evidence that astronomy is indeed quite beneficial to the society. To give you a small example, the  Global Positioning System (that we quite commonly use on a day-to-day basis for navigating from one place to another) is  a byproduct of the “Theory of General Relativity” that Einstein originally developed in 1916 to understand the birth and  the dynamics of the universe. I doubt anyone would have seen this present day application of Einstein’s theory 100 years  ago. Indeed, the fact that astronomy has survived as an important subject till present day is a testimony to the fact that it  must be beneficial for the human race.  

Astronomy has always been one of the most fascinating subjects. If you really think about it, the field of astronomy is also a  bit romantic: wondering about stars and galaxies that light up the night sky! Admittedly, there are tremendous opportunities in  this field; especially in the young and vibrant field of “Galaxy dynamics and formation”, there remains a wide landscape  waiting to be explored. In this field, we are currently trying to understand how did our Galaxy form? How is it evolving with  time? How many other Milky Way-type galaxies exist in the universe? How can we interpret the dynamical properties of  these galaxies to learn about the nature of the mysterious dark matter? Particularly in regard to this field, you can find plenty  of career options in, for instance, the U.K., U.S., Europe (specifically France, Germany, Netherlands, Sweden, Spain, Italy)  and Australia. In India, there are many other interesting fields of astronomy that you may consider pursuing (e.g., in the field of gravitational waves, radio astronomy, theoretical physics, to name a few).  

Tell us an example of a specific memorable work you did that is very close to you!  

In the field of astronomy, I am best known for my work on stellar streams of the Milky Way.  

For instance, during my Ph.D., I developed the STREAMFINDER software. STREAMFINDER is a state-of-the-art algorithm that analyses the positions and velocities of the Milky Way stars and detects stellar stream structures (see figure below where  stellar streams of the Milky Way are marked in color).  

Figure Description: Our home galaxy, the Milky Way, comprises about a hundred billion stars, and all the stars typically move on very different orbits. In this image, a linear group of colored points highlights those stars that move on very similar orbits. These structures are called “stellar streams”, and stars in a given stream originate from the same “star cluster” as they get torn off by the gravitational force of the Milky Way. The color indicates distance from Earth, with “red” denoting very distant systems (~ 100,000 light years), and “blue” denoting relatively nearby systems (~10,000 light years). These streams were detected by analysing observations of the ESA/Gaia satellite using the STREAMFINDER algorithm. These streams are currently helping us to address two fundamental puzzles of astronomy – the formation of the Milky Way and the nature of the mysterious dark matter.  

Your advice to students based on your experience? 

1> Be passionate and gritty about your field of interest. 

2> The only way to find passion is to explore: Apply for scholarships, fellowships, conference travel grants, quizzes,  competitions. Attend conferences and seminars. Also, solve as many physics problems as possible – that’s the only way to  know how creative you can be in this field.  

3> Learn to make peace with your failures: During this process of exploring and competing, you will fail. You may fail  several times. But that is okay! In fact that is good. This means you are trying something new in your life. This means you are  pushing your boundaries, learning new skills and becoming more than what you were yesterday. This means you are gaining  experience and becoming an adult. Failing is hard, I admit. But it should not deviate you from your path. Talk to your  teachers, and ask them how you can turn this failure into success. Try second time, third time. With some smartness and  experience, you should be able to crack it eventually. If you think you are failing even after trying several times, either you are doing something wrong, or you are not well equipped for the field and may consider changing it.  

 4> Fall in love with computer programming willingly, and don’t make the mistake I made :I hated computer programming  until my M.Sc. I was wrongly assuming that computer is going to play no major role pertaining to my subject. I was utterly  wrong. General advice: irrespective of whether you become a theoretical researcher or an experimental researcher, at some  point you will have to work with computers. And trust me, the knowledge of computer programming will help you immensely in your career, or at least in making your career options flexible. Try to become a master of at least one computer  programming. In astronomy, we generally use Python, C/C++, fortran or bash. 

5> Read, read, and read a bit more! Reading is essential and you can absorb unfathomable amounts of knowledge by  developing your reading habit

Future Plans?  

I was recently awarded the prestigious Humboldt Research Fellowship by Alexander von Humboldt Foundation in Germany.  I will be using this fellowship to start working at the Max Planck Institute of Astronomy (MPIA), Heidelberg, Germany from  September 2021. My broader goal as an astronomer is to address the cutting-edge problems of astronomy, and continue  contributing to the field of “Galaxy dynamics and formation”.  

I was, am, and will always be, a student of Physics. And in the field of Astronomy, sky’s the limit! (literally).