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SpaceNut

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From: New Hampshire

Registered: 2004-07-22

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Mars supply chain

Founding SpaceX employee aims to build a ‘supply chain to Mars’

Tom Mueller was a founding employee of SpaceX. He was the lead designer on the Merlin engines that power SpaceX’s Falcon 9 rocket.

In 2020, he left SpaceX and founded his own company, Impulse Space, which recently launched its first spacecraft aboard a Falcon 9 rideshare mission.

In an interview with IE, Mueller explained how his company’s Helios spacecraft could dramatically improve access to geosynchronous orbit and pave the way for future missions to Mars.
Tom Mueller is arguably one of the most important figures in the space industry today.

In 2002, Elon Musk signed him onto his new venture, SpaceX. As a founding employee, he was tasked with developing a propulsion system to help SpaceX reduce the cost of reaching orbit to fly to Mars.

During his more than two decades at the company, he oversaw the development of the Merlin engines that power Falcon 9 during their ascent and landing.

Mueller left SpaceX in 2020, and he has since launched his own company’s spacecraft, Mira, aboard a Falcon 9 rideshare mission and announced another vehicle called Helios. Not only that, Impulse Space could beat SpaceX to Mars thanks to a collaboration with Relativity Space.

A less costly alternative to Falcon Heavy
Impulse Space announced its Helios in-space propulsion system in January. The company claims it will open up access to higher orbits, much like Falcon 9 made low Earth orbit (LEO) more accessible.

While Mueller helped SpaceX cut down the costs of satellite launches with the Merlin engine and Falcon 9, Impulse Space hopes Helios will do the same with satellite launches to higher geosynchronous orbits. It will do so without building any rockets. Instead, it is developing in-space propulsion spacecraft that can ride aboard existing rockets.
Falcon 9 can easily take payloads to low Earth orbit. Still, satellite operators and scientists looking to send payloads to geosynchronous orbit (GEO) typically rely on larger rockets like SpaceX’s Falcon Heavy or United Launch Alliance’s Vulcan Centaur.

Measuring under five meters in diameter, Helios was designed to launch aboard a rocket like Falcon 9. Once deployed in low Earth orbit, at an altitude of approximately 2,000 km, it propels its payload the rest of the way to the required higher orbits.

“The key differentiator is Helios’s engine will use chemical propulsion rather than electric, to achieve up to 15,000 lbf of thrust.”

“The benefit is that the satellite operator can start their mission much sooner without having to modify the satellite itself for heavy-duty propulsion,” Mueller explained, “while also being able to take advantage of the cheaper and more frequent LEO launches, versus having to pay for a GEO launch.”
Geosynchronous orbits are typically about 35,000 km above Earth, allowing satellites to remain in a fixed position above a specific location on Earth. Traditionally, they have been much harder and much more expensive to reach.

Impulse Space’s Helios system is much more powerful than the typical in-space propulsion system, meaning it can reach the intended orbit in a fraction of the time of other systems. From the moment of deployment, Impulse Space says Helios will take approximately 24 hours to reach its intended orbit.

What’s more, using the system is much cheaper than booking a slot aboard a Falcon Heavy rocket. According to Impulse Space, using Helios aboard a Falcon 9 rocket would provide the same performance as a Falcon Heavy rocket at two-thirds of the cost.

“Today, the status quo for many satellites launched to LEO that want to get to GEO is to use electric propulsion to slowly arrive at their target orbit over a period of months,” Mueller told IE. “The alternatives are to either include extra propulsion in the satellite itself, complicating the design and increasing mass and cost, or to pay for a much more expensive launch directly to GEO.”

“Helios will change this paradigm by allowing satellites to launch to LEO, and then transporting them all the way to GEO in about 24 hours, thanks to its powerful engine,” he continued. “The key differentiator is that Helios’s engine, Deneb, will use chemical propulsion rather than electric propulsion, allowing it to achieve up to 15,000 lbf of thrust.”

Chemical over electric propulsion
In November last year, Impulse Space launched its first spacecraft, Mira, aboard a Falcon 9 rideshare mission as part of its LEO Express 1 mission. After launch, Impulse Space announced it had successfully established contact with the spacecraft.

Mira will perform last-mile delivery services in low Earth orbit, and Impulse Space already has a few customers in line to use that service, including Orbit Fab. Much like Helios, Mira uses chemical propulsion to give it an advantage over other in-space propulsion systems.

“There are a lot of learnings we’re taking from our first Mira flight into our development of Helios,” he continued. “For instance, many of the components we built for Mira, like star tracking and avionics, will be directly transferable to Helios. The experience we’ve gained operating Mira in space will also be very informative as we move forward with our Helios work.”

Companies, including Momentus Space and D-Orbit, have developed in-space propulsion systems, though these use electric propulsion. They take much longer to travel to the intended orbit and have a lower payload capacity. For example, Momentus Space’s Vigoride space tug can carry 750 kg to low Earth orbit locations. In comparison, Helios can deliver payloads weighing up to 4,500 kg to higher orbits.

“Helios’s engine is more powerful than most other in-space transportation options because it uses chemical propulsion instead of electric propulsion,” Mueller explained. “Chemical propulsion allows a vehicle to achieve much higher thrust. Helios also has a very high specific impulse, meaning that it’s incredibly efficient in how it uses its propellant, which is a combination of liquid oxygen and liquid methane.”

Impulse Space also says Helios can move itself to a graveyard orbit after a mission, meaning it won’t contribute to space debris. The space tug may also eventually be adapted to provide space debris removal services. The company aims to test fire Helios’ Deneb engine for the first time this year, with a view to a first demo flight in early 2026.

Founding SpaceX employee looks to Mars
Much in the same fashion as SpaceX, Impulse Space partly sees its satellite services as a means for funding more ambitious projects that will fly much farther into space.

The company, for example, recently announced a partnership with Relativity Space to send a robotic lunar lander to Mars by around 2026. It would be the first commercial lander to touch down on the Red Planet if successful. Moreover, if it touches down in 2026 or 2027, it could make Impulse Space and Relativity Space the first private companies to fly to Mars, ahead of SpaceX.

According to Mueller, however, the goal isn’t to beat his former employers to the Red Planet. “We’re passionate about making the inner solar system more accessible through powerful in-space transportation,” Mueller said. “More than having claims of being “first,” this is what motivates us to explore opportunities like the Impulse and Relativity Mars mission – the chance to push forward the state of the industry and open doors for others.”

Still, Mueller explained that “we’re still excited by the opportunity of a Mars mission and are in ongoing conversations with our partners at Relativity. Spaceflight is an incredibly challenging feat, and it’s important to do things the right way and take the time needed to achieve milestones safely. We’re continuing to pursue this opportunity and will share updates on timing as they are available.”

Overall, Mueller sees last-mile delivery closer to Earth and missions to Mars as part of a vast network of future missions connect us to the solar system.

“We also envision our fleet as working in a complementary fashion to help build a robust in-space logistics infrastructure,” the Impulse Space founder explained. “For instance, while Helios is like a long-haul truck that can take a lot of payload across great lengths, Mira is more like a last-mile delivery van that can nimbly get to a precise final destination. We’ll need both capabilities – along with other pieces of the puzzle – to build a supply chain to Mars.”

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,428

Re: Mars supply chain

Thanks to Void we have another to make use of in "Mars Direct 3 is a Mars mission architecture developed by Miguel Gurrea" topic.
https://www.marspapers.org/paper/Gurrea_2021.pdf

Plus Mars direct was a 40mT payload
https://www.marspapers.org/paper/Zubrin_1991.pdf

A reuseable craft requires the means to make the fuel of choice.

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,428

Re: Mars supply chain

more stuff