UG to build more detectors for ALMA radio telescope

Technicians from the Kapteyn Institute of Astronomy have been asked to build another 66 detectors for the ALMA radio telescope in Chile, together with partners in Sweden and Italy. ‘We have proved that we can build series of detectors to a consistently high standard, which makes us unique’, explains Joost Adema, who is coordinating the Groningen side of the project. The consortium with Sweden and Italy is being coordinated by the Netherlands Research School for Astronomy (NOVA).

The Kapteyn Institute at the UG has a long history of building highly sensitive instruments, which is not unusual for an institute of astronomy. ‘Most of the instruments we make are unique and you only need one’, says Adema. But the ALMA radio telescope consists of 66 dishes, each one fitted with the same equipment. ‘We’re talking about high-grade detectors that have to be totally reliable.’

Complex molecules

ALMA can analyse radiation from space at various wavelengths. A separate detector has been developed and produced for every band. In the past, the Kapteyn Institute provided detectors for Band 5 (wavelengths 1.8 - 1.4 mm) and Band 9 (wavelengths 0.5 - 0.4 mm). The latest order is for Band 2, for detecting wavelengths from 2.6 to 4.5 mm.

This wavelength enables the radio telescope to find complex molecules in space, which could have played a role in the origins of life. Life on Earth is based on complex carbon-based molecules, such as sugars or alcohols. The million-dollar question is: where did they come from? For decades, scientists studying the origins of life assumed that they originated on Earth, in shallow pools, for example. ‘But in recent years we have been discovering more of these types of molecules in space’, explains Adema.

DNA

In addition to sugars and alcohols, researchers have also come across simple building blocks for DNA in space. Astronomers therefore want more detailed information about where these building blocks for life are found. ‘This will help us to understand how they evolved, and perhaps arrived on Earth from outer space.’

It would also be interesting to search for planets in ‘hotspots’ in space, where large numbers of these types of molecules are found. These would possibly contain many more of these types of building blocks for life, increasing the chances that this is where life originated.

But the detectors need to be developed and built before researchers can make these discoveries. ‘It takes two years to work out how to build these detectors’, says Adema. They are being developed in collaboration with colleagues from the University of Gothenburg (Sweden) and the University of Bologna (Italy). This will be followed by a three-year project in which the entire series will be built, tested and delivered.

Metalworking

Engineering companies from the region are helping the Kapteyn Institute to build the detectors with services such as metalworking and building printed circuit boards. Not many institutes are able to build a whole series of detectors of a consistently high quality. ‘We have proved that we can build series of detectors to a consistently high standard, which makes us unique’, says Adema. This is why they were awarded this new project.

Six people will work on the project in Groningen. The total budget (including for the partners) is around € 13 million, € 11 million of which will go to the Kapteyn Institute. ‘Some two-thirds of our budget will be spent on specialist components, and the rest on staff and business operations.’ If all goes well, the last detectors will be shipped to Chile in five years’ time. ALMA will then be in an even better position to search for the building blocks of life between the stars.