SAN FRANCISCO – Rubicon Space Systems won a NASA contract to develop a 110-newton ASCENT thruster prototype.
“It’s bigger than any ASCENT thruster we’ve sold previously,” Daniel Cavender, director of Rubicon, a division of Plasma Processes, told SpaceNews.
And as far as Cavender can tell, it’s the most powerful ASCENT thruster being built for the government. Cavender, who worked on ASCENT missions in previous roles at NASA, said the new contract could pave the way for ASCENT thrusters to serve as the main propulsion for large satellites, lunar landers and space stations.
First, though ASCENT thrusters must clear the power hurdle.
While some space system developers are eager to dispense with many of the safety precautions required for working with hydrazine, ASCENT is notoriously power hungry.
“The big question has been how far can ASCENT scale without becoming unreasonably power hungry,” Cavender said. “We need to address the power disparity that has slowed this transition away from hydrazine to more green fuels.”
To reduce the power demand for the 110-newton ASCENT thruster, Rubicon engineers focused intently on thermal design.
Simply scaling up small ASCENT thrusters would have produced a 110-newton thruster that required 400 to 500 watts to preheat. Instead, for the prototype scheduled to be delivered to the NASA Marshall Space Flight Center later this year, “we are pushing close to 100 watts,” Cavender said.
The 110-newton ASCENT thruster is “an important part of our roadmap,” Brandon Denton, Rubicon principal propulsion engineer, said in a statement. “With ASCENT’s nearly 50 percent higher impulse density from hydrazine, our 110-newton thruster will rival most bipropellant thrusters out there.”
ASCENT stands for Advanced Spacecraft Energetic Non-Toxic Propellant. ASCENT was developed by the U.S. Air Force Research Laboratory in the 1990s.
