Stefan received a Phillip Leverhulme award for his work on star and planet formation.

Dr Stefan Kraus

Star researcher Dr Stefan Kraus is a a lecturer in Astrophysics whose research into protoplanetary discs was recognised by the Leverhulme Trust.

Stefan spoke to us about how it felt to win this award, how the grant will help his research and why research into planetary formation shows that there could be millions of planets that contain life.

What is your current research about?

In my research, I study the disks around young stars. These disks are crucial for our understanding of star formation and they provide the stage for the formation of planets.

I use a novel technique, optical interferometry, which combines the light of physically separate telescopes in order to generate images of unprecedented sharpness, up to a hundred times sharper than those of the Hubble space telescope, for instance.

With this tool I determine the physical conditions in the inner disk regions, study mass infall and mass ejection processes, and search for gaps that are carved out by young, orbiting planets.

How did it feel to have your research recognised by the Leverhulme trust?

It’s certainly a great honour that my work has been recognised with a Philip Leverhulme Prize.

Given that I work with a relatively young and emerging technique, I feel that the Prize gives also some recognition to the impressive advancements that have been achieved in my research field in the recent past.

How will the grant help your research?

The grant will allow me to hire a postgraduate student or postdoctoral research assistant that will work with me on the modelling of our observational data.

In my studies, I often combine data from different facilities or data that has been obtained with complementary techniques.

While this approach allows me to obtain a global view of the disk structure, it is exceptionally work-intensive, as I have to analyse datasets from various origins and find a model that is able to reproduce all constraints.

I look forward to work on these aspects now within a small team.

How did you first get interested in astronomy?

At age 11 I got my first telescope. This was a rather simple instrument with a good optics, but cheap mechanics and a poor mounting.

After a short time I got dissatisfied and started building new components, such as an own computer-controlled mounting, a CCD camera system, and an intelligent enclosure.

Over six or seven years I wrote a software package that was able to operate the observatory fully automatically and that analysed the data in an automatic fashion. For some time, I used this telescope to track asteroids and to search for new objects.

This passion for observational astronomy stayed with me during my physics studies and the years since.

You have previously worked in Germany and the USA, what brings you to Exeter?

Exeter has an outstanding research group in the field of star formation and on extrasolar planets.

Many group members work on aspects that are highly complementary to my research, which can result in very exciting collaborations.

I was very happy to join the group when I had the opportunity.

How can a member of the public understand the impact of your research?

Personally I see astronomy as an integral part of our culture, in a similar way as music, literature, or philosophy is. It touches fundamental questions, such as where our solar system comes from, or whether we are alone in the universe.

People have asked these questions since dawn of time, but it is just now that technology allows us addressing many of these questions in a meaningful way.

As individual scientists we are only able to focus on a specialised aspect of these big questions, but ultimately it is integrated into common knowledge as science progresses.

Some pieces also reach the public through press images, press releases, or articles in popular magazines.

What do you think the future holds for research into planet formation?

We are living in a very exciting age for planet formation research, in particular due to the powerful instruments that are just coming online.

First, there is the ALMA array that will image planet formation signatures in the cold, outer disk. Instruments at the VLTI array will probe hotter material in the inner disk regions.

With these facilities, it should be possible to detect some protoplanets that are still undergoing formation, allowing us to study planet formation in action. But they will also leave some important open questions, for instance about the earliest stages of the planet formation process and the formation mechanism of terrestrial planets, which happens very close to the star.

Answering these questions will require an even more powerful telescope array. I am co-chairing an international initiative, in which we aim to develop the scientific and technological roadmap for such a facility.

What makes you tick?

The potential for unexpected discoveries.

As in every job there is a lot of routine work but regularly one discovers also something surprising or finds that all pieces of a puzzle fall suddenly into place.

These are the moments that make it worthwhile.

Do you think there might be life on other planets?

One intriguing discovery of the last few years has been that planet formation is a very common and efficient process. In fact, there seem to be more planets than stars in our milky way!

A substantial fraction of those planets should be located within the so-called ‘habitable zone’, where liquid water can exist.

Accordingly, there might be millions of potentially habitable planets, and it is very plausible that biological evolution could have started and created life on some of these worlds.