Your Majesty, your excellencies, Professor Ewine van Dishoeck, dear colleagues, Ladies and Gentlemen.
It is a great honour and a great pleasure for me to motivate the choice of Professor Ewine van Dishoeck as recipient of the Niels Bohr International Gold Medal 2022.
It is said that when a butterfly flaps its wings in Brazil, it may set off a tornado in Texas. Such a statement, attributed to the mathematician Edvard Lorenz, is made to make us wonder at how the smallest things in our chaotic world can influence events on a much larger scale. Today’s Niels Bohr Gold Medallist, Ewine van Dieshoeck, takes this statement to the extreme.
In her research she shows how single atoms and molecules, which are a 100 million times smaller than your average butterfly, can influence the formation of stars and planets, and even the evolution of galaxies – structures that are a 100 trillion times larger than the distance from Brazil to Texas.
Thus, she draws a direct line from Niels Bohr’s studies of atomic structure to some of the greatest questions that mankind has asked through time: “How was our world created?” and “What is the origin of life?”.
When Niels Bohr proposed his atomic model in 1913 he used quantization of the momentum of the electrons with respect to the atomic nucleus – their angular momentum – to determine their stable orbits. When an electron transitions from an orbit of high energy to one of lower energy it will emit a photon – a quantum of light – with a wavelength determined by the energy difference between the two orbits. Since the stable orbits are characteristic of the specific type of atom or if the atoms are bound together in a molecule, of the specific type of molecule, this means that each atom or molecule emits and absorbs light at specific wavelengths. We can say that they have a characteristic spectral fingerprint. Indeed, one of the successes of Niels Bohr’s atomic model was its ability to explain the characteristic spectrum of light emitted and absorbed by the hydrogen atom.
Ewine van Dishoeck makes use of these characteristic spectral fingerprints of atoms and molecules to detect them in interstellar space and in regions of star and planet formation. Highlights of her research include the disclosure of the chemistry of interstellar carbon monoxide with potential impact on the isotopic composition of water on our Earth, the detection of interstellar organic molecules and insights into their formation pathways, with potential impact on our understanding of the origin of life, and insight into the physical structure and chemistry of planet-forming discs around young stars, with impact on our understanding of the formation of The Solar System.
As I entered the field of astrochemistry as a young researcher, Ewine was clearly among the brightest stars in the field. Not only is she rumoured to be the most cited scientist in astrochemistry, she is also an undeniable presence at conferences and meetings. Her astounding overview of the field, her drive to get to the bottom of scientific questions and to focus on the most important challenges to our understanding, as well as a lack of patience for the woolly and the imprecise make her a fixpoint in the ongoing scientific discussion and in the community at large.
Ewine van Dishoeck is not only a true scientist, she is also true to science. Thus, she is an inspiration to us all, scientists young and old.
Today’s Gold Medallist comes from the home country of Vincent van Gogh. With the help of paint and brush he created beautiful pictures of the starry night that we still marvel at today. Like Vincent van Gogh, Ewine van Dishoeck makes beautiful pictures of the starry sky. But she has a somewhat more expensive taste when it comes to her choice of tools. Her newest paintbrush is a $10 billion space telescope.
During these last few months, I am sure that we have all marveled at the beautiful pictures delivered by the James Webb Space Telescope of distant galaxies, of molecular clouds in interstellar space and of some of our local planets. The James Webb Space Telescope is, however, so much more than an expensive paintbrush.
I think it is fair to say that we right now stand on the threshold of the James Webb Space Telescope era in astronomy, astrophysics and astrochemistry. The unrivalled spatial and spectral resolution of Webb holds the potential to observe the earliest galaxies, to allow us to witness the formation of new stars and planetary systems, and to reveal signatures of life in the atmosphere of planets around foreign stars.
While the rest of us are standing on the threshold to the James Webb Space Telescope era, Ewine van Dishoeck has already stepped through the door. Along with her collaborators, she is among the first to report the detection, with Webb, of the spectral fingerprints of complex molecules frozen out in ices on nanoscale dust grains around a forming star. Such observations may allow us to understand the complex processes involved in star and planet formation, and to determine whether the molecular building blocks of life can form in interstellar space, even before the formation of stars and planets.
Ewine van Dishoeck has played a key role in shaping the future of astrophysics and astrochemistry research in the decades to come. She has done this through her involvement with the development of the mid-infrared instrument – MIRI – on the James Webb Space Telescope, through her patronage of the Atacama Large Millimeter/sub-millimeter Array and through a relentless pushing of the-state-of-the-art in laboratory astrochemistry and in molecular astrophysics modelling. However, her influence on the future of astrochemistry is not limited to scientific breakthroughs, hardware and new methodologies. Maybe the most important mark that she has placed on the future of research in the field is via the many PhD students, post docs and collaborators that she has interacted with and whose research trajectories she has helped shape over the years.
Ewine van Dishoeck is Professor of Molecular Astrophysics at Leiden University and External Scientific Member of the Max-Planck Institut für Extraterrestrische Physik in Garching. Until this summer she was the President of the International Astronomical Union, representing 10,000 astronomers from close to 100 different countries. Ewine van Dishoeck has strong ties to Danish research with collaborators at Århus University, Copenhagen University and the Technical University of Denmark.
The Niels Bohr International Gold Medal committee finds that Ewine van Dishoeck’s work represents an important extension of Niels Bohr’s seminal work on the atomic model to modern day astrophysics. Ewine van Dishoeck’s work is based on the detection of atoms and molecules in interstellar space via their spectral signatures, and is aimed at elucidating how the microscopic atomic and molecular world impacts the macroscopic structures of stars, planets and galaxies. The scientific quality and the implications of this research for our understanding of the universe and our origins make Ewine van Dishoeck an excellent choice for the Niels Bohr International Gold Medal 2022.