Research group The group for stars, planets and astrobiology

Up to six positions will be available in the areas of Stars, Exoplanets, Supernovae/Computational Astrophysics, Galaxies, and Cosmology at the department of astronomy.

Arjan Bik at the Department of Astronomy has been promoted to docent. Arjan’s research focuses on the effect massive stars have on their surroundings, both at small scales (on proto-planetary discs), and on larger scales (on the interstellar medium inside star-forming galaxies).

On October 18 2025, the 4-metre Multi-Object Spectroscopic Telescope (4MOST) facility, installed on the VISTA telescope at the European Southern Observatory’s (ESO) Paranal Observatory in Chile, obtained its first light. This milestone is a crucial step in the lifecycle of a telescope and marks the moment in time when it is ready to begin its scientific journey.

A study led by Jenny Frediani at Stockholm University has revealed a planet-forming disk with a strikingly unusual chemical composition: an unexpectedly high abundance of carbon dioxide (CO₂) in regions where Earth-like planets may one day form. The discovery, made using the James Webb Space Telescope (JWST), challenges long-standing assumptions about the chemistry of planetary birthplaces. The study is published in Astronomy & Astrophysics.

The exoplanet 55 Cancri e probably has an atmosphere dominated by carbon dioxide or carbon monoxide, according to a new study published in Nature. The planet was previously speculated to lack atmosphere, but new observations from the James Webb Space Telescope have enabled researchers to study the atmosphere around the Earth-like rocky planet.   

Where do we come from? How were all our atoms created? These are some of the intriguing questions that a group of astronomers called the R-Process Alliance are trying to answer. Today, they publish a new groundbreaking study in the prestigious scientific journal Science, where they show footprints from the cosmic creation of super heavy elements. Terese Hansen, researcher at the Department of Astronomy, is one of the co-authors. Where do we come from? How were all our atoms created? These are some of the intriguing questions that a group of astronomers called the R-Process Alliance are trying to answer. Today, they publish a new groundbreaking study in the prestigious scientific journal Science, where they show footprints from the cosmic creation of super heavy elements. Terese Hansen, researcher at the Department of Astronomy, is one of the co-authors. "Rapid neutron capture is an awe-inspiring cosmic phenomenon, responsible for the creation of the heaviest elements in our universe," explains Dr. Terese Hansen, Stockholm University, astronomer and co-author on the paper. "However, the site where the r-process occur which lead to the creation of super heavy elements has been a mystery to us, at least until now”. Dr. Hansen is one of the founding members of the R-Process Alliance. The R-Process Alliance has unveiled a groundbreaking revelation in their latest project, cracking the code to the formation of super heavy elements. As these elements form in the r-process to achieve their super heavy status, they become inherently unstable, ultimately fragmenting into elements like silver and palladium. This cascade of elemental disintegration has left a tell-tale signature in the atmospheres of stars, a silver fingerprint that the R-Process Alliance believe is the remnants of super heavy elements breaking apart. "In our pursuit of understanding the r-process, we have identified a distinct accumulation of silver and palladium in the atmospheres of stars," notes Dr. Hansen. "These elements are the offspring of super heavy elements that have undergone fragmentation, providing a tangible insight to the processes occurring in the extreme cosmic environments that form the nebulae where new stars are born." What makes this discovery particularly significant is that it offers a glimpse into the production of elements heavier than any man-made counterparts. While these super heavy elements remain elusive to direct observation, the indirect evidence found in stellar atmospheres serves as a testament to what may have happened in the environment that eventually led to the birth of new stars. The implications of this research extend far beyond the realm of astrophysics. By meticulously mapping the chemical compositions of stars, the R-Process Alliance is not only uncovering the ‘where’ and ‘when’ of rapid neutron capture events but also providing crucial insights into the quantity of heavy elements, such as silver, generated by these cosmic explosions. In short: it provides us with an unprecedented understanding of element formation in the universe. The study is based on observation of 42 stars in the MilkyWay. The team investigated 31 elements observed in 34 previous studies.