Astronaut Tim Peake praised Northern Ireland's "cutting-edge" technology as he opened a new space propulsion centre at Thales, in east Belfast.
It's the first centre of its kind in the UK - and a major step forward for Northern Ireland's space sector.
After he opened the new centre, Peake also met children from 200 local schools on a visit to W5.
Thales will be manufacturing propulsion systems for sending high-tech satellites into space - for everything from telecommunications to weather-forecasting - as a result of Thales' £6m investment in its Belfast factory.
Peake famously spent six months in the International Space Station, where he entertained the world and inspired the next generation of scientists.
He described the range of his work for the European Space Agency.
"I can go from melting metal alloys in the European lab, to the US laboratory, working with proteins for the pharmaceutical industry.
"It gives me as much, if not more pleasure, to come back and visit industry that is driving investment in cutting-edge technology."