Karen Pollard and the Music of the Stars

This is the second article in my series of ‘Women in Astronomy’ article series, in honour of the International Astronomical Union’s Women and Girls in Astronomy month (February).

Dr Karen Pollard is an Associate Professor of Astronomy at the University of Canterbury in New Zealand. She is also the Director of the University of Canterbury Mount John Observatory, and her research interest is stellar evolution and pulsating stars.

Karen Pollard in her office in the Department of Physics at the University of Canterbury, with her first telescope.

Origins and Early Influences

Karen started her astronomical journey at a young age. She was born in Christchurch, New Zealand, and has been living there for most of her life. She was a creative child, and loved reading fantasy, sci-fi and astronomy books, doing art, playing the recorder, writing stories, and doing math. She wanted to be an astronaut as she was so inspired by reading her books about astronomy, although sadly she has motion sickness, but she still aspired to do science as a career!

One of Karen’s favourite astronomy books as a child, ‘The Junior True Book of Moon, Sun and Stars’.

At the age of around nine years old, she wanted a telescope, and asked her parents about getting one. Her wish was granted, and she got a little telescope which her parents had gotten from a garage sale, in her stocking at Christmas. Karen was thrilled with her telescope and used it to observe objects like the moon, the naked-eye planets: Jupiter and its moons, Saturn and its rings, star clusters like Omega Centauri, and even binary stars like Alpha Centauri! Once she even got up at 4am (and got up her family too) to observe Halley’s Comet.

Karen’s first telescope, a little 30mm zoom 10x – 30x telescope.

Throughout the rest of her childhood and teenage years, Karen had plenty of astronomical influences to keep her inspired and motivated. For instance, during her childhood/teenage years, the Voyager I and II spacecraft were travelling through the solar system, and she pinned several posters of the Voyager images all over her bedroom.

One of Karen’s favourite posters was the image of Saturn from Voyager II. Image source: NASA.

In addition, she was fascinated and inspired by Carl Sagan’s TV series, ‘Cosmos: A Personal Voyage’, and the BBC radio show ‘The Hitch-Hikers Guide to the Galaxy’, which motivated her, and inspired her passion in astronomy, and space in general.

“The cosmos is also within us. We’re made of star stuff. We are a way for the cosmos to know itself.” – Carl Sagan (Karen’s favourite quote from ‘Cosmos: A Personal Voyage’.)

At high school, not only was Karen enjoying her studies in science, maths and writing, but she was also very involved in her school community and participated in a lot of sports. She was in the first teams for athletics, cross-country, road racing, soccer, basketball, and cricket. After high school, Karen decided to study towards an engineering intermediate degree at the University of Canterbury (UC), because she enjoyed physics, maths and chemistry and wanted to keep her options open.

University Years

Karen was a bright student, and passionate about her studies. After her first year of university, she was invited to do an accelerated Physics/Chemistry Honours degree. She chose Physics (even though she also enjoyed and was good at Chemistry) and graduated with her Bachelors of Science with Honours degree in Physics in 1988. She won a scholarship during her summer vacation from 1987 – 1988, and travelled to the Australian National University in Canberra, Australia. There, with two professional infrared astronomers, she worked on a stellar project at Siding Springs Observatory, New South Wales for a few weeks.

Australian National University’s Siding Springs Observatory in New South Wales, Australia, where Karen worked on a summer project. Image source: Wikipedia.

Karen started her PhD in Astronomy in 1989, studying R Coronae Borealis and RV Tauri variables (some unusual supergiant stars), and got to do a lot of observing at the University of Canterbury’s Mt John Observatory. Her fellow classmate from her undergraduate days, Michael Albrow, was also doing a PhD in Astronomy, where his project was modelling Type I Cepheid stars. During their PhD, Karen and Michael got married.

A photo of the University of Canterbury’s Department of Physics and Astronomy staff and graduate students. (Karen second-to-right in sitting row).

Starting Her Professional Career: Post-Doctorates

After earning their PhDs in 1994, Dr Pollard was offered a post-doctoral research fellowship at the South African Astronomical Observatory (SAAO) in Cape Town, South Africa, and Dr Albrow was also offered a reputed post-doctoral research fellowship, which allowed him to work in Cape Town with Karen.

First Post-Doctorate

When they got to Cape Town in 1995, they found it a different environment from New Zealand, yet enjoyed it a lot. For her post-doctorate research, Karen used the SAAO telescope infrared equipment to study the dust environments around evolved stars that experienced mass loss.

The South African Astronomical Observatory (SAAO) telescopes, where Karen obtained data for her first post-doctorate research project. Image source: Wikimedia.

During their time in Cape Town, Karen and Michael, and two SAAO astronomers founded the Probing Lensing Anomalies NETwork (PLANET), a new worldwide collaboration, the aim of which was to employ a network of telescopes around the world (Chile, Australia and South Africa) in longitude, to undertake intensive photometric observations of microlensing events to search for extrasolar planets. This collaboration started in 1995 and has been continued since! Karen left in 2010 to pursue other research, however PLANET is still successfully ongoing.

Around the same time in 1995, Karen also worked with MACHO (another microlensing collaboration similar to PLANET, but in search of dark matter instead of extrasolar planets). She searched MACHO’s database of photometric data of the Large and Small Magellanic Clouds, in search of RV Tauri and Type II Cepheid stars (these are types of variable stars), because it was unknown whether RV Tauri stars existed outside our galaxy. Karen found that these stars did indeed exist outside the Milky Way, because she found evidence of them in the Large Magellanic Cloud (which is a dwarf galaxy). She also found new star members of the Type II Cepheid class of variable stars. This was some leading-edge research because Karen had solved the problem which had plagued astronomers for several years!

Karen showed that Type II Cepheid and RV Tauri stars were related since they obeyed the same Period-Luminosity-Color relationship, which she derived from the data from the MACHO project.

That same year in 1995, Karen and Michael attended the historic conference in Florence, Italy, where the discovery of the first extrasolar planet around the star 51 Peg was announced! The next year in 1996, they attended another conference in Paris, France, where Michael presented a paper on his research on Type I Cepheid star models, and Karen presented her work about finding RV Tauri stars in the Large Magellanic Cloud. Both of their papers were highlighted in the conference summary by a distinguished professor from Harvard University, which led to more recognition of their work.

An artist’s impression of the first extrasolar planet found, 51 Peg b, and its star, 51 Peg. Image source: Wikipedia.

Second Post-Doctorate

After Karen’s post-doc, Karen and Michael returned to New Zealand in 1997. Karen obtained another post-doctoral research fellowship while Michael became a co-PI on a funded research project, both at the Department of Physics at UC. Additionally, they brought with them a proposal from the Director of the SAAO for UC to collaborate with them on a new telescope project, the Southern African Large Telescope (SALT), which was planned to be an 11m telescope. The Vice-Chancellor of UC supported this collaboration, and allocated UC research money, to design and build a high-resolution echelle spectrograph for the SALT telescope (which was successfully designed in 2005).

Karen and some staff and students at UC.

Three years later in 2000, Michael was offered another post-doctoral research fellowship at the Hubble Space Telescope Science Institute in Baltimore, USA. Karen says she drew a circle of reasonable commuting distance and applied for jobs in that radius. She was offered a position as an Assistant Professor in the Physics Department at Gettysburg College in Pennsylvania, where she taught astronomy and physics courses. The same year, they were both offered a position as a lecturer in the Department of Physics and Astronomy at UC, and they split the position in half, i.e. Karen and Michael each had a half-time position.

Becoming A Professor

They started their positions in June 2001, where Michael started his work full-time and Karen initially worked half-time so that she could remain flexible with her children. They have been working at UC ever since. A few years later in 2003, Karen organised a large international conference, the International Astronomical Union Symposium 193 on Pulsating Stars in the Local Group’, which was quite successful.

Logo of the International Astronomical Union, a section of which Karen organised a successful international conference for. Image source: Wikimedia.

Throughout this time, both Karen and Michael continued their PLANET collaboration research, and even received a grant in 2005, allowing them to travel to do observing, and to present their results at conferences. The PLANET collaboration had some successful papers, one of them about the discovery of a 5.5 Earth mass extrasolar planet discovered through microlensing in 2006, and another paper demonstrated (through statistics of several years’ worth of data) that every star in the galaxy has at the very least one planet, in 2012, both of which Karen and Michael were involved with.

Karen and Michael were in the New Zealand media for the PLANET collaboration’s 2006 extrasolar planet discovery event.

In 2008, they took a sabbatical year in Europe, and worked with many collaborators. Karen wrote a proposal, ‘The Music of the Stars’ to use Mount John Observatory’s 1m telescope and the HERCULES spectrograph to do cutting-edge research on asteroseismology, which is the determination of the interior structure of stars by studying their tiny surface vibrations. During this time, she also became the Director of the Mount John Observatory.

Karen with the 1m McLellan Telescope at Mt John Observatory.

Current Work

With so much academic involvement, Dr Pollard leads a busy and active life. She teaches undergraduate astronomy, astrophysics and physics courses, and a typical work day for her involves a lot of teaching, giving lectures, overseeing tutorials and labs, and the usual university administrative work. Besides teaching, she also supervises her graduate (Honours, Master’s and PhD) students, and spends a lot of time answering emails, proposals, reviewing and refereeing articles for several scientific journals, and meeting with her colleagues, collaborators, students, and others.

Karen, along with some of her undergraduate and graduate students, on a trip to visit NASA’s SOFIA plane.

She also squeezes in the admin work for Mt. John, because as the Director of Mt John Observatory, Karen has to go over observing proposals which are submitted by fellow astronomers, researchers, students, and international collaborators, and allocate observing time at the telescopes and create schedules. She even helps organise trips to Mt John for the UC Alumni Association, or the Elaine P. Snowden program (an astronomy camp for enthusiastic Year 13s interested in pursuing a career in astronomy/space science), or even her colleagues and collaborators.

Furthermore, Karen is a Councillor of the Royal Astronomical Society of New Zealand (RASNZ), and she says that it is a more local role, which gives a point of contact between local astronomical societies and local astronomy amateurs or enthusiasts and gives a nice link between amateurs and professionals. In the past, she has been a member of various astronomical organisations, such as the International Astronomical Union, and the Royal Society Committee on Astronomical Sciences.

She also needs to do her research, and finds time to do this. She often lets her graduate students help her with research, and she does a lot of collaboration, often on an international scale. Karen finds the best way to do research is through collaboration, which is something that she enjoys a lot. She regularly attends a lot of conferences to present her scientific work, and has organised several conferences too. She also gets to travel the world for things like visiting professorships and fellowships.

During the summer of 2017 – 2018, Karen and Michael were invited to be Senior Visitors at the Paranal Observatory in Chile, where they did some research.

Her research is very interesting and varied. She has studied and continues to research stellar variability, evolved pulsating stars, asteroseismology of pulsating stars, protoplanetary disks, planets around young stars, luminous blue variable stars, stellar atmospheric analysis, and the microlensing search for extrasolar planets. She is very passionate about what she has termed ‘The Music of the Stars’, which is the idea that through asteroseismology, we can study the pulsations, or vibrations of stars (since many periodically swell and contract), and learn a lot about the nature of the star.

Karen at SALT in South Africa with a colleague.

Outside of her academic work, Karen also leads a very active life, similar to her high school days. She does Tai Chi, which she had picked up at high school, and continued as a university student, which she found very calming and helpful to relax. After a brief period of no Tai Chi, she has recommenced her practice of Tai Chi again. Likewise, she also does some yoga, aerobics and swimming, and bikes to the university.

I asked Karen if she had any advice for women considering careers in STEM, and she says that being able to balance things is very important. In addition, having a good support system enables one to have a balanced life, for example, she and her husband Michael Albrow support each other, and being prepared to work the job half-time each, as well as dedicating time with family, has helped both of them live a balanced life.

Karen at the Very Large Telescope in Chile.

I am truly inspired by Dr Pollard’s work in astrophysics as a Woman in Astronomy, and wish her all the best for future endeavours and research! Many thanks to Dr Karen Pollard for this interview.