Lee Billings describes the ARM policy mess.
It’s a mission they came up with for an overpriced, non-existent and unnecessary rocket looking for a mission. And note this rationale:
She and other NASA officials note that the advanced propulsion required for ARM would be enabling technology for a broad range of future missions and that ARM would be a crucial test for many deep-space activities crucial for someday reaching Mars. And it would do all this while keeping astronauts sufficiently close to home so that if something goes wrong, they could attempt an emergency return to Earth.
Safety is the highest priority.
I find it a hoot that NASA says they can have the robotic tug at an asteroid by 2021. The James Webb Space Telescope program was begun in 1996. They hope to launch it in 2018, but I wouldn’t hold my breath. This is, on its face, ridiculous.
Off topic, but this screamed “How about on a spaceship?” to me:
http://www.wired.com/2014/11/nano-sub-co2-scrub/
A submarine is a perfect test bed for lots of space technologies. Same goes for NEEMO, and I hope they test it there too.
I’m actually a fan of at least the underlying concept of the Asteroid Redirect Mission (though if they were trying to do the mission for the most affordable price tag, they probably wouldn’t be using either SLS or Orion for the project). Grabbing a boulder off an asteroid and bringing it back to lunar orbit basically adds another moon to the earth-moon system, but one that delta-V wise is just about as easy to reach as L1 or L2. It also gives them a chance to flight test some of the planetary defense technologies people have come up with over the years, and get a little more experience with robotic operations at asteroids. But the key to me is that you’re adding another more reachable moon to cislunar space, one that >99.9% of its mass will still be in a 100+ yr stable orbit once NASA’s done with it.
Are there definite implementation details that could make this concept easier, cheaper, and better? Sure. But is the underlying concept of bringing a rock back to cislunar space silly? No.
~Jon
(PS: I am a bit biased–we’re getting paid to do a study on one of the asteroid capture mechanisms for the ARM mission. I’m not counting on a follow-on contract, but it is one of our bigger contracts at the moment)
Grabbing a boulder off an asteroid and bringing it back to lunar orbit basically adds another moon to the earth-moon system,
But we haven’t explored those we already have.
It’s been shown mathematically that Earth must have at least one “temporary moon” at any given time. If nature’s already done 95% of the work for us, why not take advantage of it?
Locating those mini-moons might not be easy, but I suspect astronomers could do it for a small fraction of the $1B being mooted for the ARM.
you’re adding another more reachable moon to cislunar space, one that >99.9% of its mass will still be in a 100+ yr stable orbit once NASA’s done with it.
At which time it becomes a national monument, like the Apollo landing sites?
This is the government that recently declared meteorites to be “antiquities” rather than minerals, making public lands off-limits to prospectors. The same government that declares lunar samples to be “irreplaceable national treasures.” Do you think they’re going to allow you to pilfer their rocks?
What Jon said. I’m no fan of SLS, but the basic idea of ARM seems pretty attractive. If it’s easier to bring the rock to the astronauts than vice versa, why do it the hard way?
I agree an ARM is a good mission, but only if done with commercial launchers. The same is true for Mars sample return and a Europa mission, simply because they could establish a propellant market. They only make use of the higher throw weight of SLS by using it to launch additional propellant, so they are not using any unique SLS capability. Just goes to show how utterly useless SLS if even its proponents can only come up with missions for it that can also be done by other launchers.
I agree an ARM is a good mission, but only if done with commercial launchers.
Then why not do the whole thing commercially?
Remember that NASA didn’t start talking about this until *after* Planetary Resources proposed the exact same mission.
It’s surprising how the same people who complained about the Space Shuttle competing with private enterprise and pleased, even thrilled, about NASA using ISS, ARM, etc. to compete with private enterprise.
There’s also the usual naïveté in assuming that the government will do things the way you want, just because you want it. That’s never worked in the past, but it will this time. “Law of averages,” right?
Once the project is underway, of course, everyone will scale down their wishes to fit whatever NASA is gracious enough to offer. Just as expectations for COTS and CCDev have been scaled down every time NASA changed the terms of the deal. In the end, everyone will pretend that whatever they got was just what they wanted all along.
Surely, there has to be a better way?
How about this for an idea. Obviously NASA only plans to return a very small sample of the asteroid to Earth, because the sample has to be brought inside the Orion by an astronaut.
Wouldn’t it make more sense to use a commercial launcher to send up a PICA-X heat shield and a parachute (plus accessories) and bring back a much, much larger hunk of the rock? Instead of hauling back 200 pounds of asteroid, a dedicated capsule could re-enter with 5 to 10 thousand pounds of asteroid.
Why not use a really big rock and just drop it on Washington / Moscow / Beijing / Paris? 🙂
“It’s a mission they came up with for an overpriced, non-existent and unnecessary rocket looking for a mission. ”
Check out the list of authors on the Keck Report. Chris Lewicki, John S. Lewis, Don Yeomans, etc. No, they aren’t shills for SLS. They’re well known asteroid guys.
Developing mining asteroid technology will be a process of trial and error. Gathering this experience on an asteroid in heliocentric orbit would be extremely difficult. Launch windows years or decades apart, trip times the better part of a year. Light lag latency often the better part of an hour.
In contrast a rock parked in lunar orbit would have launch windows and trip times on the order of weeks or days. Light lag latency around 3 seconds. This allows for a faster paced learning curve. 3 or 4 orders of magnitude less time consuming than a test bed in heliocentric orbit.
Mining heliocentric orbits without that experience. That’s Syke’s Kool-aid.
Redirecting an asteroid will also be a process of trial and error and for the same reasons. Moving one to Earth orbit, even a relatively stable orbit like L4 or L5, is non-trivial. And then you’re still faced with the same issues except the light lag. It’s all a matter of trade-offs. Having many groups pursue this with different strategies will yield faster reduction in unknowns.
Parking at L4 or L5 isn’t being proposed. If you want to comment on the Keck Report, you’d do well to read the Keck Report.
It would take about about 6 years to bring back a rock.
Once parked in lunar orbit, launch windows from a given low earth orbit would open each two weeks. Trip time would be a little less than a week. As mentioned light lag latency is about 3 seconds.
In contrast let’s look at an asteroid in an earth like orbit. Say with a semi major axis of 1.1 AU. Such a rock would have a period of 1.154 years. Earth’s period is 1 year. So synodic period would be (1.154*1)/(1.154-1) or about 7.5 years. Trip time would be about 6 months.
So let’s say the first microgravity excavator doesn’t work as planned and we want to send a modified version 2. We’d have to wait 7.5 years for another launch opportunity. If it takes 6 tries to land a satisfactory piece of equipment, that’d be 45 years.
In contrast 6 missions to an asteroid parked in lunar orbit could be easily be done in a few years. Heck, with trip times of ~1 week, we could send humans to the site to tweak the equipment.
No, the issues aren’t the same.