Pretty much. For it to be effective as a relay it would need some large dishes and a large power supply (large solar array) plus a good amount of propellant for station keeping.
So it would be a quite expensive option when it is only really required for a few weeks a year.
Also with the mass it would likely have to be I doubt there was a heavy lift rocket that could do the job in recent times until Falcon Heavy came along.
plus a good amount of propellant for station keeping
Aren’t L4 and L5 naturally stable points? A large propellant budget shouldn’t be required for station keeping.
They are much more stable than other locations but are not completely stable, so station keeping is required. In a theoretical two body system Lagrange points would be perfectly stable but that is not the case with the solar system. Eg: The orbit of the moon ever so slightly effects the Sun - Earth Lagrange points.
The JWST is a good example. The expected observational lifespan of the telescope is based on how long it is able to remain at L2.
NASA Says Webb’s Excess Fuel Likely to Extend its Lifetime Expectations
The JWST is a good example. The expected observational lifespan of the telescope is based on how long it is able to remain at L2.
I thought L1, L2, and L3 were unstable but L4 and L5 were stable. Hence why asteroids and other detritus tend to collect at L4/L5.
Edit: Huh, it looks like the stability of L4 and L5 are dependent on the mass ratio of the two bodies. The ratio works out for the Sun-Earth system, so it should also work for the Sun-Mars system.
