An international team of astronomers, including Elisa Costantini (SRON/UvA), has for the first time directly measured how much sulfur occurs in gaseous and solid form in the interstellar medium. This helps to understand how gas clumps together to form stars and planets.

A European team of astronomers led by the Netherlands have uncovered a large filament of hot gas connecting four galaxy clusters. The filament contains so-called warm-hot intergalactic medium. The hot gas spans over a distance of 23 million light years, is more than ten million degrees hot, and may be part of what astronomers call the ‘missing normal matter’. The team used two X-ray space telescopes: the Japanese Suzaku and the European XMM-Newton. Publication on June 19^th in Astronomy and Astrophysics.

The board of the Pastor Schmeits Prize for Astronomy Foundation has decided to award the 2025 Pastor Schmeits Prize to two individuals: Yamila Miguel (SRON/Leiden University) and Else Starkenburg (University of Groningen). The prize was presented on 28 May 2025 during the 80th Dutch Astronomers Conference (NAC) in Berg en Dal.

A small international team of astronomers including Silvia Toonen (UvA) and Gijs Nelemans (RU, KU Leuven and SRON) has discovered two white dwarf stars orbiting each other that will merge and explode into a type Ia supernova. This missing link in astronomy has long been predicted. The researchers publish their findings today in Nature Astronomy.

Using the XRISM X-ray telescope, astronomers have observed hot gas sloshing back and forth in the core of a cluster of galaxies. This provides the first direct evidence of gas motions driven by a collision on cosmic scales. Publication in Nature.

Het wetenschappelijke consortium van ESA’s toekomstige NewAthena röntgentelescoop heeft haar doelen voor de missie gedefinieerd in een publicatie in Nature Astronomy.

Astronomers have used the James Webb Space Telescope to measure the infrared spectrum of a rocky planet in the auspicious planetary system of TRAPPIST-1. It is what you’d expect from a planet covered in volcanic rock. Another scenario includes an atmosphere full of CO2 and smog. The team, including Michiel Min (SRON), publishes the results in Nature Astronomy.

On December 10^th, ESA’s X-ray observatory XMM-Newton celebrates 25 years in space. SRON contributed to one of XMM-Newton’s three instruments—the Reflection Grating Spectrometer. From planets to black holes, the space telescope has delivered many ground-breaking observations of a variety of celestial objects. Let’s take a look at four fascinating discoveries from the past five years.

Kunnen we de grootste structuren in het universum onderzoeken door te kijken naar de kleinste deeltjes? Daarover gaat het onderzoek van Lydia Stofanova, promovendus aan de Leidse Sterrewacht en SRON—het Nederlandse instituut voor ruimteonderzoek. Ze bestudeert hoe elementen zoals zuurstof de grootschalige structuur van het universum beïnvloeden. Op 13 november verdedigde ze haar proefschrift.

An interdisciplinary research consortium, including Floris van der Tak (SRON/RUG) and Michiel Min (SRON) has been awarded an NWA grant by the Dutch Research Council (NWO) to investigate the origin of life on Earth and in the universe. The so-called PRELIFE consortium (Pathways, Reactions and Environments) receives €6.7 million to explore this research question.

The Astrophysics Centre for Multimessenger studies in Europe (ACME) has kicked off its activities in Paris. This EU-funded project aims to optimize the  European-wide accessibility and cohesion of multiple astroparticle and astronomy research infrastructures, such as VIRGO, KM3NeT, Auger Prime and LOFAR, to realize multi-messenger astrophysics.

Following its launch on September 7th, 2023, and the subsequent series of tests, the XRISM X-ray telescope has produced its first two scientific papers. The team marveled at a temperature of ten billion degrees Celsius inside a supernova remnant. And it measured the distance of the dust ring around a supermassive black hole. In the case of NGC 4151, this turns out to be 0.1 light years. SRON has developed the filter wheel and an X-ray source used to calibrate the energy scale of the Resolve instrument.

SRON astronomers have for the first time mapped the outflows from one of the closest quasars— I Zwicky 1. Quasars are bright cores of galaxies powered by the supermassive black hole in their center. The team has probed gas outflows in I Zwicky 1 to map its system of clouds being blown away at tens to thousands of kilometers per second. Publication in Astronomy & Astrophysics.

Every year SURF organizes its Research Support Championship Awards to give a platform to innovators of research support. This way they can increase their impact and reach and inspire others. SURF is a cooperation of Dutch educational and research institutions. This year, Jelle de Plaa (SRON) receives this award at the SURF Research Day.

SRON astronomer Floris van der Tak has received an ENW-M1 grant from NWO to study the life cycle of stars and planets. Together with a PhD student, he will study the presence of carbon and nitrogen in tenuous gas clouds—the precursors of baby stars. They will analyze data from the recently conducted balloon mission GUSTO, for which SRON developed the cameras.

Astronomers have discovered possible atmospheric gases on 55 Cancri e, a hot rocky exoplanet at 41 light years from Earth. This is the best evidence yet for an atmosphere around a rocky planet outside our solar system. Gas bubbling up from a lava-covered surface possibly feeds an atmosphere rich in carbon dioxide or carbon monoxide. The researchers, including astronomers from SRON and Leiden Observatory, publish their findings in Nature.

The Japanese X-ray telescope XRISM has officially started its nominal phase of operations. After its launch on September 7^th 2023, XRISM went through a series of checks in the commissioning phase, which is now completed. To mark this milestone, new images have been released to the public. SRON has contributed the filter wheel including calibration source to the Resolve instrument.

On Sunday 3 March 2024, the third mobile planetarium of the Netherlands Research School for Astronomy (NOVA) was officially inaugurated – the SRON planetarium. This took place at the alumni day of the IMC Weekend School at Nyenrode Business University in Breukelen. The event also marked the start of a project to use the inflatable stars to reach more children in socio-economically disadvantaged and rural neighbourhoods.

After a record-breaking 57 days, 7 hours and 38 minutes, NASA’s balloon telescope GUSTO completed its flight above Antarctica by landing on the ice by parachute. The mission was designed to last 55 days. GUSTO has observed atomic clouds in our own galaxy and its nearest neighbor with far-infrared cameras, developed by SRON and TU Delft.

The Laser Interferometer Space Antenna (LISA) opens up a new part of the gravitational wave spectrum as the first space-based detector.  It is now officially adopted by the European Space Agency (ESA) as one of its large class missions. Launch is scheduled for the mid-2030s. The Netherlands plays a large role in the development of hardware and software. 

With the release of its first two images, JAXA’s X-ray telescope XRISM has officially reached the milestone of First Light. The images show the galaxy cluster Abell 2319 and supernova remnant N132D, demonstrating XRISM’s large field-of-view and high spectral resolution. SRON has developed the filter wheel and an X-ray source used to calibrate the energy scale of the Resolve instrument.

NASA’s GUSTO balloon telescope has launched from Antarctica on December 31st. The far-infrared observatory carries out the first large-scale survey with velocity-resolved imaging of the spectral lines emitted by three cosmic elements between stars. GUSTO is equipped with three 8-pixel cameras. SRON and TU Delft made one of those and contributed to the other two.

The discovery of a planet that is far too large for its sun defies models of solar system and planet formation. In an article published in Science, researchers report the discovery of a planet over thirteen times as heavy as Earth orbiting the ultra-cool dwarf star LHS 3154, which is nine times less massive than the Sun. The mass ratio of the newly discovered planet and its parent star is more than a hundred times higher than that of Earth and the Sun. One of the authors is Yamila Miguel (SRON/Leiden Observatory).

An international team of astronomers, co-led by Michiel Min (SRON), has discovered a silicate-based weather system on a fluffy gas planet around the star WASP-107. It is the first time that scientists find clouds and rain made of sand. They also conclude that the temperature deeper in the atmosphere is rising surprisingly rapid. Publication in Nature.

A group of scientists, including Michiel Min (SRON), have for the first time observed ammonia isotopologues in the atmosphere of a celestial body. They used the James Webb Space Telescope. It gives astronomers new tools to deduce how gas giants are formed. Publication in Nature.

NASA’s GUSTO balloon observatory has arrived on Antarctica onboard the Wallops C-130 airplane. It is scheduled for launch around the 15^th of December. GUSTO is equipped with  three 8-pixel far-infrared cameras delivered by SRON and TU Delft and will carry out the first large-scale survey with velocity-resolved imaging of the spectral lines emitted by three cosmic elements between stars.

After lift-off on September 7th 2023, the X-ray space telescope XRISM goes through various tests to check whether all parts have survived the launch. All detector elements of the Resolve instrument, which SRON has contributed to, have now picked up X-rays from the calibration source. They achieve an energy resolution better than 5 eV.

The XRISM X-ray telescope is successfully launched on the early morning of September 7th from Tanegashima Space Center in Japan onboard a JAXA H-IIA rocket. SRON Netherlands Institute for Space Research is part of the consortium and has developed the filter wheel including calibration system.  

Terri Brandt has made her way from NASA to start as the new head of SRON’s astrophysics program. ‘SRON’s unique triangle of expertise provides us with many possibilities for audacious science.’

NASA’s GUSTO balloon telescope has passed its payload pre-shipment review. It will now ship from the University of Arizona to Johns Hopkins Applied Physics Laboratory for the final integration onto a gondola. This means GUSTO is on schedule for launch in December from Antarctica. SRON and TU Delft together developed GUSTO’s three 8-pixel cameras that will observe cosmic material between stars.

A Dutch consortium led by SRON has received an NWO grant of twelve million Euro, making The Netherlands an important partner within ESA/NASA’s LISA mission—the first space detector for gravitational waves. It also prepares The Netherlands for its role within LISA’s terrestrial cousin—the Einstein Telescope.

Planetary researcher Yamila Miguel (SRON/Leiden University) receives an ERC Consolidator grant of two million Euro to study the interior structure of giant planets in our Solar System. She will use data from the Cassini and Juno missions around Saturn and Jupiter, together with the detailed data on exoplanet atmospheres obtained with the recently launched James Webb Space Telescope.

An international team of astronomers, led by Yamila Miguel (SRON/Leiden Observatory), has found that Jupiter’s gaseous envelope doesn’t have a homogeneous distribution. The inner part has more metals than the outer parts, adding up to a total of between 11 and 30 earth masses, meaning 3-9% of Jupiter’s total mass. This is a high enough metallicity to conclude that kilometer-sized bodies—planetesimals—must have played a role in Jupiter’s formation. Publication on June 8th in Astronomy & Astrophysics.

Mercury harbors water ice in the shadows of the steepest craters around its poles. But it is unclear how those water molecules ended up on Mercury. Now a new simulation shows that incoming minor bodies such as asteroids, comets and dust particles carry enough water to account for all the ice sheets present. The study could form the basis for new research on water in exoplanetary systems. Publication in Icarus on April 19th.

An international team of astronomers made the most detailed images of the largest cosmic shock wave visible from earth. These gigantic shock waves are much larger than our entire galaxy and they form when clusters of galaxies collide in what are the most energetic events after the Big Bang.

Astronomen hebben een model over hoe botsende clusters van sterrenstelsels de verschillende stadia van hun botsing doorlopen, waarbij ze steeds een nieuwe vorm aannemen. Een stompe vorm verandert in een scherpe kegel, die weer transformeert tot de vorm van een tong. Die eerste en die laatste zijn al vele malen waargenomen, maar de scherpe kegel ontbrak nog. Tot nu. Publicatie in Astronomy & Astrophysics op 7 december. 

An international team of researchers, including astronomers from ASTRON, SRON and Leiden University has for the first time observed the full extent of the evolution of hot gas produced by an active black hole. Eventually this hot gas encompasses a much larger area than previously thought and impacts objects residing at great distances. Publication in Nature Astronomy. 

SRON and Nikhef receive an ENW-M grant (€500,000) from NWO for the development of the photoreceivers for the gravitational wave detector LISA. It enables them to further develop the existing prototype towards a final version that meets the strict accuracy requirements. They work together with the Dutch companies BRIGHT Photonics and SMART Photonics to produce a photodiode that is large and noiseless enough to pick up LISA’s laser beams of only one nanoWatt.

Our telescopes have never detected a black hole more massive than twenty times the mass of the Sun. Nevertheless, we now know of their existence as dozens of those black holes have recently been “heard” to merge via gravitational wave radiation. A team of astronomers led by Peter Jonker (SRON/Radboud) has now discovered that these seemingly disparate results can be explained by biases against massive black holes in conventional telescope observations. 

Conventional theory states that light stars like our Sun gently blow off their layers when they die, while heavy stars explode as a supernova. But for some reason, we are so far failing to find supernovae from stars heavier than eighteen solar masses. Now a team led by SRON astronomers finds a new clue that fuels this apparent mystery. Publication in Astrophysical Journal Letters.

An international team of astronomers, including Elisa Costantini (SRON), has for the first time observed light from the far side of a black hole. Initially this light, in the form of X-rays, is emitted by a corona surrounding the black hole. A series of strong X-ray flashes from the front was followed by a series of weaker flashes, which the researchers determined are from the back side and reflected off the black hole’s accretion disk. Publication in Nature.

Between the stars in our Milky Way, vast amounts of tiny dust grains are floating aimlessly around. They form the building blocks of new stars and planets. But we still don’t know what elements exactly are available to form planets like Earth. A research team at SRON led by Elisa Costantini has now matched observations from X-ray telescopes with data from synchrotron facilities to create a map of interstellar grains in the Milky Way.