MPE News

Interview with Prof. Paola Caselli, coming soon as director to MPE

February 17, 2014

Starting 1st April 2014, Paola Caselli will take up a directorship at the Max Planck Institute for Extraterrestrial Physics. So far, she held several research positions at the Harvard–Smithsonian Center for Astrophysics, the University of California at Berkeley, the Harvard University, and the Osservatorio Astrofisico di Arcetri (INAF), and is currently part of the astrophysics group at Leeds University. Her main research interests are astrochemistry, galactic and extragalactic star and planet formation, molecular astrophysics and astrobiology.

Future MPE director Paola Caselli Zoom Image
Future MPE director Paola Caselli

How did you get interested in astronomy?

When I was 12 years old and in my last year of middle school, I started to think a bit more seriously about my future. At that time, I thought that the most fascinating things I could do were art (especially painting) to express my "inner world", or science (especially physics and astronomy) to explore and try to understand the "outer world".

I knew I had to decide, as I had to choose between a scientific and an artistic high school, but it was hard… until my teacher suggested that I should read a book by Fred Hoyle, “The Black Cloud”. This "living cloud” and the ingenious astronomers at the Palomar Observatory in California fascinated me so much that I wanted to be one of them. So, this book was the turning point and I decided to pursue a scientific career.

It is intriguing to me that I am still studying dark clouds and organic material in space - after all these years. Besides, I ended up at the University of Leeds, where Fred Hoyle studied chemistry toward the end of his school career. During the past six years I have actually lived less than 10 miles away from the village in West Yorkshire where he was born.

 

Close-up of the gas cloud L1544 with the water spectrum seen by the Herschel satellite, taken from the centre of the pre-stellar core. Together, the emission and absorption signatures indicate that the cloud is undergoing gravitational contraction, that is, it is collapsing to form a new star. Herschel detected enough water vapour in L1544 to fill Earth's oceans more than 2000 times over. Zoom Image
Close-up of the gas cloud L1544 with the water spectrum seen by the Herschel satellite, taken from the centre of the pre-stellar core. Together, the emission and absorption signatures indicate that the cloud is undergoing gravitational contraction, that is, it is collapsing to form a new star. Herschel detected enough water vapour in L1544 to fill Earth's oceans more than 2000 times over. [less]

Why did you choose star & planet formation and astrochemistry as your research interest? What do you find fascinating about these topics?

The driving mystery behind this is linked to one of the big questions we all have: what are our origins?

Studying regions where stars and planets are forming now gives us clues on the process that gave birth to our solar system. Molecules are the best tools to study the physical properties of these stellar nurseries and unique tools to unveil the dynamical evolution of star and planet forming regions - astrochemistry is fundamental to progress in this field.

If we want to decipher the molecular signals gathered with our telescopes, we need to understand the chemical processes and how they are linked to the physical structure of an astronomical object. Also, it is fascinating that most of the observable molecular material in the universe is made out of organic molecules mixed with water. It is in the harsh environment of interstellar space that the first steps toward life are made.

 

Recent image of Paola Caselli at the site of the ALMA Observatory. The "Atacama Large Millimeter/sub-millimeter Array" is an interferometer of 66 high-precision radio telescopes in the Atacama desert in Northern Chile. The telescope array will observe at millimetre and sub-millimetre wavelengths to probe the very first stars and galaxies, and directly image exo-planets, possibly discovering the first traces of life. Zoom Image
Recent image of Paola Caselli at the site of the ALMA Observatory. The "Atacama Large Millimeter/sub-millimeter Array" is an interferometer of 66 high-precision radio telescopes in the Atacama desert in Northern Chile. The telescope array will observe at millimetre and sub-millimetre wavelengths to probe the very first stars and galaxies, and directly image exo-planets, possibly discovering the first traces of life. [less]

In astronomy, what is the most pressing question for you?

Stars and planets are the outcome, when dense fragments of giant molecular clouds collapse because of their own gravity. How do these fragments form and how do they evolve in different environments? These are some of the pressing questions that we will address. We will need to run comprehensive simulations, including magnetic fields, turbulence, chemistry, and use observational results as well to put stringent constraints on theory.

Similarly pressing is the formation of protoplanetary disks within the dense cloud fragments and how their characteristics change with the physical structure of the parent cloud.

Finally, it is important to understand how the complex organic molecules, observed in cold pre-stellar clouds and in warm regions close to young stellar objects, form and evolve. Are these molecules important for the chemistry of the future planetary systems? Are they stored in the icy mantles of dust particles and then transported to the protoplanetary disks and eventually to planet surfaces? Amino acids (the building blocks of proteins) have been copiously found in meteoritic material. Are those the result of reprocessing of the organic material observed in star forming regions?

 

<p>This simulation shows how ALMA would observe dust continuum emission at 300 GHZ of a self-gravitating protoplanetary disk around a star with the same mass as our Sun. This image is extracted from a recent paper by Douglas, Caselli et al. 2013. </p>

This simulation shows how ALMA would observe dust continuum emission at 300 GHZ of a self-gravitating protoplanetary disk around a star with the same mass as our Sun. This image is extracted from a recent paper by Douglas, Caselli et al. 2013.

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Do you already know Munich?

I have been to MPE long time ago (1995) as a postdoc, but only for three months because I got my permanent position at the Arcetri Astrophysical Observatory at around the same time. So, it is almost as starting from scratch…

 

What will be the first thing you do when you arrive?

Getting to know my colleagues better and starting to build up the Centre for Astrochemical Studies at MPE! It will be great to be next door to so many great scientists and I am thrilled by this amazing opportunity to assemble an astrochemistry group.

 

Is there something that you will miss from the UK?

I will miss my friends and colleagues, who have helped me so much in the past years by taking care of my daughter when I had to travel. This has been fundamental for me and my career. A big “Thank you!” to them! 

Also, I will miss the quiet and beauty of the Yorkshire Dales. A piece of my heart will remain there, on top of some moors.

However, I am looking forward to exploring the Alps and the beautiful countryside around Munich.