One of the coldest, hottest and most powerful superconductor electric rocket thrusters to be tested in space is being built in a hi-tech shed at the bottom of Wainuiomata Hill.
The superconductor magnet and its accompanying thruster are being assembled in Seaview, Lower Hutt. It will be checked in Houston, launched in Florida and installed on the space station, where it must take its turn to be tested in space for the first time.
“We’re going to have [to] turn off during space walks to ensure we don’t interfere with the astronauts’ equipment if they’re in the area,” Randy Pollock, the mission’s American chief scientist and engineer, says.
In the humming Seaview shed, Pollock is supervising the assembly of a superconductor magnet that runs at minus 200 degrees Celsius, outside a core thruster that runs at a blue-hot 1000C. All of it can just about be held in your two hands.
“The group here has a unique knowledge of superconductors,” he says.
“We’re the only group in the world that is both building our magnets and building our thrusters and operating them, frankly, in the same room.
“The magnets were built over here behind me, the system for the space station is being assembled there, and in the back of the room is the test facility for our thruster.”
The thruster tester is a shining stainless steel vacuum tube the size of a car, nicknamed Geraldine – Gigantic and Extremely Radical Atmospheric-Lacking Device for Interesting and Novel Experimentation. (“Engineer humour,” someone comments.)
Two years of work on the “Hēki” experiment has come down to an intense six to seven weeks of testing and assembly by three researchers in blue smocks and masks in a clear plastic booth like a quarantine unit, bolting bits together, religiously recording every single step.
Then to Texas, for more tests. Then to space, for more again.
The aim, eventually, is to come up with an electric rocket engine way more efficient than those in use now – which are already sending Nasa spacecraft to the asteroid belt – that with wee squirts of argon (it shoots out of the thruster in tests at 10-20 kilometres per second) could push a rocket to Mars.
“If you ran a chemical rocket, you might fire for tens of seconds or even maybe tens of minutes,” Pollock says.
“This you will run for weeks or months or years ... so it enables a class of missions that just wouldn’t be practical because of the amount of fuel you would normally have to carry.”
“If you want to move large amounts of cargo to the moon, to Mars.”
None of this would be taking place in New Zealand if not for Nick Long.
The country’s grandfather of superconductors, Long has spent three decades helping crack the puzzle that makes them usable in experiments like Hēki.
“When they were first discovered, people thought, ‘Oh, this is great, we’re gonna have wires, you know, before we know it,’” Professor Long, director of the Paihau-Robinson Research Institute at Victoria University, says.
“And actually, it turned out to be incredibly difficult.”
The superconductor magnet runs at -200C. Photo / RNZ / Reece Baker
Now, though, the crystals for superconductors can be grown into 100-metre lengths and bought off the shelf, to wrap into the dense coils at the heart of the magnets.
Hēki presents a milestone for Long and his team to see the impact in space in a new way – if they can only get past the nerve-racking countdown to a February launch on a SpaceX rocket from Florida.
“It’s your baby you’re sending up there and it has to work, right?” Long says.
“You can’t go up and fiddle with it.
“I mean, I’m a laboratory experimentalist and I always like to fiddle with things. They never work first time.
“Luckily, we’ve got people here who know about sending things into space and making sure they’ll work up there, when we, you know, can’t get in there with a screwdriver.”
Randy Pollock is one of those people and he has already been to Mars, in a sense: a rock sniffer he made for Nasa’s jet propulsion lab in California is currently on the front of the Perseverance rover as it seeks signs of ancient life on the red planet.
But unlike the rover that never returns, New Zealand’s landmark superconductor thruster will.
“It goes out an airlock and will spend several months operating on the outside of the space station,” Pollock says.
Inside the vacuum chamber. Photo / RNZ / Reece Baker
“At the end of that time, it comes back in and, for the first time in my career, I will actually get the hardware back at the end of a mission.
