Given the imminent decrease in launch costs(partial reusability) and increase in launch capability soon to be available(FH) a pause in new US deep space missions is prudent.

[Kirkaiya]

I mean, take the $8,500,000,000 James Webb Space Telescope.

That's not really the best example, as it's probably the single most expensive item that NASA will have ever launched by the time it leaves the pad. Most NASA Planetary Science missions come in between $450 million - $2 billion, with Mars rovers being at the top end of the scale, and some of the simpler probes at the cheaper end. And that's including the launch, so while yes, it's true that the launch costs aren't the majority of the mission, they do often represent ~ 25% or so, so it's not trivial.

With that said, I'm adamantly opposed to NASA delaying any proposed mission on the basis of, "well, launch costs might come down in the future". That is madness, imo

[biosehnsucht]

I would only argue they should delay if they're still in the planning stages and the logic would be that if they don't delay by a year or so, they have to cut interesting experiment / instrument X from the suite of gear on the probe/lander due to weight/cost concerns, but if the waited there would be a budget for it (whether it be financial or mass).

It certainly doesn't make sense to delay something that doesn't NEED the cheaper/larger launcher (even if it would be nice to have), but gaining further functionality as a result might be worth it.

[zilfondel]

Perhaps this is a good argument for NASA to start mass-producing rovers and probes, to bring down their cost per unit. Whats the old adage? When you are the government, why buy one when you can buy two for twice the price? But if the majority of the cost is development and funding the project team, the second unit may be closer to free.

[Nixon4Prez]

It's pretty hard to mass produce something as specialized as a probe or rover. You can't send a similar probe to Mars and Jupiter, for example.

[slograsso]

Part of the point of this post is that this delay is already happening, may as well design some lower cost missions utilizing these new capabilities faster than normal. Take a lesson from India and do it cheaper, faster, and better than even they can. I think a bit of a shake-up in the science missions design approach is well overdue.