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[Trekkin]

(silently titters at the highly absurd notion of an interstellar scramjet, that is fusion powered, and uses a huge magnetic ram scoop to suck in interstellar hydrogen for fuel.)

To be fair to Bussard, though, he was working on estimates of interstellar matter density that were orders of magnitude too high. It's not so much "highly absurd" as based on faulty data.

[Madman198237]

It's usually referred to as a ramjet. I suspect that if you could get it moving fast enough it would work even with lowered densities, but it needs fuel to get to speed, but it needs speed to get fuel. Paradox!

[wierd]

Solution:

Fire the whole damned ship out of a mass driver-- THEN turn on the engine.

[Trekkin]

It's usually referred to as a ramjet. I suspect that if you could get it moving fast enough it would work even with lowered densities, but it needs fuel to get to speed, but it needs speed to get fuel. Paradox!

Not Bussard's original design, no; the drag on the electromagnetic ramscoop far exceeds the thrust that could be generated by fusing together the collected matter regardless of scoop size or speed. Such a ramscoop makes a fine brake, though.

One alternative is to carry fusion fuel onboard and use the ramscoop as a propellant source once the ship is over the critical speed, which significantly reduces the required propellant mass at launch. Using an externally accelerated particle stream to provide the initial acceleration would bring the propellant requirements down to an absolute minimum, particularly if the propellant tanks could be loaded from the stream itself.

Kind of like firing the ship out of a mass driver, just gentler.

[Baffler]

NASA and Roscosmos revealed plans today to cooperate on a jointly operated station in lunar orbit.

https://www.theguardian.com/science/2017/sep/27/russia-and-us-will-cooperate-to-build-moon-first-space-station
http://www.telegraph.co.uk/news/2017/09/27/russia-us-agree-cooperate-building-first-lunar-station/

They're in the early stages, just working out common technical standards for parts to be manufactured later, but from the looks of it this is the real deal.

[sluissa]

Sounds great. US had already planned a token one. Maybe working together we can figure something out thats actually worthy of the attempt.

[WillowLuman]

Can't wait to see it in action! When are the prospective dates?

[Trekkin]

Can't wait to see it in action! When are the prospective dates?

Apparently construction is supposed to start in the mid-2020s. As this is beyond the end of the current presidential administration, expect it to never happen; one of the first things every new President does is tell NASA what their multi-decade-long plan should be. Even if their mandates stayed the same for long enough, they'll never have enough money to do anything manned again after the ISS is shut down.

This is a pipe dream. This is a bunch of political administrators demanding the nerds in their employ do something cool and overruling their objections because who listens to scientists anyway? It will never happen.

[Reelya]

Well yeah, even JFK's moon landing could have occured towards the end of his administration, if he'd survived and run for two full terms (1960-1968).

And Nixon decided to support the Space Shuttle shortly after his inauguration in 1969. While the first orbital tests took as long as 1981, in 1969 it might have appeared plausible that they could have them up and running before the end of Nixon's presumed 2 terms in office.

So ... if you want Trump to authorize something, tell him it'll be up and running by 2024 and it's 100 times as likely to get funded.

[martinuzz]

Opportunity has now been roving the surface of Mars for 5000 days.
Quite impressive, for a rover that was made to last 90 days.

[smjjames]

Opportunity has now been roving the surface of Mars for 5000 days.
Quite impressive, for a rover that was made to last 90 days.

Yeah, our technology on Mars continues to surprise us with resilience.

[Madman198237]

We built it to last, after all. It had to make 90 days for sure or it was a colossal waste of money.

By the way, it was not a colossal waste of money.



But yeah, score 5000 for modern engineering. We sent a probe to a place no human has ever visited, fully prepared to lose it en route, on landing, and every day of its mission. Now, in one of the harshest imaginable environments, it is still running, at almost 56 times its life expectancy.

[Starver]

All hail Opportunity! (But given how we treated it and Spirit...)

[redwallzyl]

There's gold in them their stars!

http://www.npr.org/sections/thetwo-way/2017/10/16/557557544/astronomers-strike-gravitational-gold-in-colliding-neutron-stars

[Jopax]

Juno takes some sexy french girl photos of Jupiter, oh myy.