91直播 researcher helps capture most detailed picture of the Milky Way鈥檚 crowded heart
Researchers at The University of Manchester have played a key role in a new scientific release from the European Space Agency鈥檚 Euclid mission, unveiling the most detailed photo ever made of our Milky Way galaxy鈥檚 centre in visible light.
The image, which contains more than 60 million stars, offers scientists an unprecedented view of the galactic bulge 鈥� the dense, bright heart of our Galaxy 鈥� and could help researchers confirm the existence of any exoplanet found in this region and measure their mass.
The new data comes from the Euclid Galactic Bulge Survey, a dedicated observing programme designed to support the discovery and study of exoplanets using a technique known as microlensing.
Captured over around 26 hours on 23 March 2025, the Euclid space telescope covered nine neighbouring fields of view, . The result reveals a region of sky packed with stars, nebulas and star clusters in extraordinary detail.
, Astrophysicist at The University of Manchester, said: 鈥淥pening Euclid鈥檚 eyes towards the centre of our Galaxy was a very exciting moment for the team. It was the culmination of years of preparation and simulations to ensure Euclid could observe such a crowded region of the sky successfully, and without impacting on Euclid鈥檚 main science goals. The view Euclid gives us of the Galactic Centre region is absolutely stunning.鈥�
The new observations show how Euclid鈥檚 capabilities can also be used for a broad range of astrophysics.
In this case, researchers are using the mission鈥檚 exceptionally sharp visible-light observations to identify the host stars to planets that cause microlensing events. Microlensing occurs when a foreground planetary system passes in front of a distant background star, briefly magnifying its light.
Dr Kerins co-led the Euclid Exoplanet Science Working Group between 2023 and 2025 and helped lead the effort to secure approval for the Galactic Bulge Survey, shape how it would be carried out, and help coordinate its successful execution.
The work required significant innovation, as Euclid was not originally designed to observe such a densely crowded region of the sky. Dr Kerins worked closely with colleagues within the Euclid Exoplanet Science Working Group, as well as the Euclid Project Scientists, instrument teams and spacecraft operations teams across the Euclid Consortium. He also helped to press the science case to Euclid colleagues and to ESA and international partners involved in Euclid. Extensive simulations and technical studies were undertaken to ensure the spacecraft could operate effectively in these conditions without affecting its core mission to study dark matter and dark energy.
The Euclid Galactic Bulge Survey targets regions rich in past microlensing events observed from the ground, where the lens and source have since begun to separate.
鈥淭his time baseline makes it possible to track the motion of the host stars and better characterise the planetary systems, ultimately enabling more accurate mass estimates for planets as small as Mars,鈥� says Dr Kerins.
Because the centre of the Milky Way is so densely populated with stars, it provides one of the best places in the sky to look for these events. 鈥淭owards the centre of the galaxy, there is one chance in a million for a star to be magnified, while it would be one in a billion on other lines of sight.鈥� states Matthew Penny, Assistant professor at Louisiana State University and current lead of the Euclid Exoplanets team. Dr Penny is a 91直播 Physics undergraduate and postgraduate alumnus.
The survey is expected to help scientists better characterise known planetary systems and prepare for future discoveries. In particular, the Euclid data will provide an important reference point for observations to be made by NASA鈥檚 upcoming Nancy Grace Roman Space Telescope, which will repeatedly observe the same region of the sky as part of its own microlensing and transit planet-hunting programmes.
Roman has recently arrived at the Kennedy Space Centre and is due to launch on August 30th this year. The European Space Agency is a partner in Roman and Dr Kerins is the ESA-appointed scientist to the Roman Galactic Bulge Time Domain Survey. Dr Kerins leads the exoplanet demographics working group within the transit science team that is expecting Roman to discover around 100,000 exoplanets across the Galaxy.
By comparing Euclid鈥檚 earlier images with future exoplanet detections from Roman, researchers expect to be able to confirm transiting planets more robustly and determine the masses of microlensing planets with greater precision.
Dr Kerins adds: 鈥淲e are at the dawn of an exciting new age of exoplanet discovery, and Euclid has just fired the starting pistol鈥�.