Successful first test for inflatable telescope
By Heather Allen
The secrets of the universe’s origin came one step closer earlier this month with the successful first test of a new inflatable radio antenna.
Niels Vertegaal, a PhD candidate from Eindhoven University of Technology (TU/e) is developing the antenna to help him realise his goal of examining the origins of the universe. The telescope will operate from the far side of the moon, free from earthly interference, which will enable it to detect these signals. The Big Bang theory sets the origins of the universe at around 13.8 billion years ago, within the scope of the antenna, which can capture faint, 14 billion-year-old signals in space.
The experiment was conducted in Sheffield, England, where Mr Vertegaal enlisted the help of the company Sent into Space, who specialise in executing and supervising this type of experiment. On 6th December, the weather conditions were favourable to allow the prototype inflatable radio telescope and weather balloon to climb into the stratosphere to an altitude of 30 kilometres. Once the weather balloon reached 20 kilometres, the antenna started to unfold. At 30 kilometers, with the air getting thinner and thinner, the balloon started to bloat, due to the pressure difference. Eventually, according to plan, the balloon tore, and a parachute then brought the equipment safely back to the ground.
During the experiment, the antenna did unfold completely, but later than Mr Vertegaal had expected. However, the antenna was operational for long enough for him to run enough measurements to determine whether the antenna was functioning properly.
Following the test, Mr Vertegaal said: “I still need to analyse the data, but I already saw that the antenna does work. Either way, I’m happy with how everything went.”
So why an inflatable antenna? It’s all down to cost, Mr Vertegaal explains: “Because every gram that goes into space is very costly. So the question is how you can make an antenna that’s large in space, but very small and light when it’s launched. In a vacuum you only need a tiny bit of air to inflate something.”
When launched, the antenna is contained in a small (ten centimetre) cube. Inside is a paper-thin film, which measures one metre square when unfolded. The film is covered by a two-micrometre thick conductive layer of copper, which functions as a radio receiver. The process of unfolding the antenna is conducted by blowing compressed air into its arms, followed by a small dose of CO₂. Prior to the experiment, Mr Vertegaal released a video of laboratory tests, where the antenna resembles a balloon being inflated, slowly revealing its final shape.
A consortium, which includes Radboud University Nijmegen and TU/e, is working on submitting a proposal to the European Space Agency. The goal is to use an inflatable antenna as a radio telescope on the far side of the moon.
“I really hope that space exploration missions to the moon will end up embracing this idea,” Mr Vertegaal said. “With an antenna that can capture ultralow frequencies behind the moon, free from interference from earth, we expect to gather information on the origins of the universe.”
Source https://www.tue.nl/en/news-and-events/news-overview/08-12-2023-research-into-the-big-bang-an-inflatable-antenna-in-space