A decision on the location of the underground gravitational wave observatory is due in late 2026 or 2027. The Netherlands, Belgium and the German state of North Rhine-Westphalia are preparing a joint “bid book” for the Meuse-Rhine Euroregion, where the three countries meet. Italy, which has proposed hosting the detector on Sardinia, has long been regarded as their main rival.
The eastern German state of Saxony had previously hinted at an interest in hosting the project, which could provide an economic boost to the former mining area. Its candidacy was officially confirmed last week.
What makes this development particularly noteworthy is Saxony’s plan to collaborate with Sardinia. This was confirmed last weekend by Günther Hasinger, the spearhead of the Saxon bid, in Belgian newspaper Het Belang van Limburg. Their joint proposal involves two detectors in an alternative configuration. While the observatory’s originally proposed design is triangular, Italy has long advocated for a cheaper L-shaped alternative. To achieve the same measurements as the triangle design, an L-shaped detector would need to be paired with a second L-shaped detector at a suitable distance. According to Hasinger, this option – with one detector at each site – has now become the “priority”, and Saxony and Sardinia will investigate it together.
The position of the German federal government may prove crucial. Last summer, Germany endorsed the Einstein Telescope project by placing it on a priority list of major scientific projects, but without indicating a preferred site. For North Rhine-Westphalia, federal funding for the construction of the observatory in the Meuse-Rhine Euroregion bid is a prerequisite for the state to make a “substantial” contribution as well. Hasinger has said that if the German federal government backs the Euroregion bid, Saxony will withdraw from the project entirely, even from a potential joint bid with Sardinia.
Amid the growing competition, the Euroregion bid continues to evolve. In an attempt to secure more political support, there are hopes that Luxembourg will join the candidacy, as Sjoerd Sjoerdsma – CEO of Einstein Telescope Netherlands – confirmed to BNR earlier this month. Talks are currently underway. Meanwhile, Flanders has increased its pledge from €200 million to €500 million. The Dutch government has already committed €870 million and Wallonia €200 million. Total construction costs are estimated at a minimum of €2 billion.