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Comment by T-A | Hacker News Reader

From the article:

Once the Gateway is up and running, the PPE element will provide power (in the 60-kilowatt), high-speed communications, attitude control, and Solar-Electric Propulsion (SEP) capabilities. This will allow it to alter its lunar orbit as needed, giving crews greater access to the lunar surface than was ever possible with conventional missions.

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So instead of launching the vehicle into whatever plane you need for a specific mission, they’re going to do a plane change manoeuvre for the entire station for each mission?

If it takes no fuel (from being solar-electric powered), and can be accomplished in parallel while the spacecraft on Earth is prepared, why not? Sounds reasonable to me.

Plane changes always require fuel. Solar-electric propulsion, in particular, requires fuel. Its high specific impulse means that it needs less fuel, but also would take many months for a small change of orbital plane.

Requires solar fuel, which is free...

Many months is ok, because it can happen in parallel with the spacecraft being prepared on Earth.

It uses energy from the sun to turn xenon gas into plasma and shoot it into space. This makes it use 10 times less propellant than conventional systems.

The xenon gas is the propellant. This still comes from the earth so it's far from free. It's just more efficient.

There is no such thing as "solar fuel". Nothing in space flight is free except failure.

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