So the location of the Apollo 12 S-IVB is known, any chance of finding the four panels connecting the S-IVB to the CM? They would be a challenge to find. Would it even be possible?

Would a future deep-space rendezvous with Pioneer 10/11 or Voyager 1/2 be possible?. I'm sure we have pretty accurate trajectory data for them, but how close would that get you? Once you got there, would you still have to search around with telescopes or radar to find them?

Just asking...

I'd love to see a recovery mission for some of these "ancient" spacecraft. But finding a needle in a haystack might be easy in comparison.

A future assignment for astronautics grad students: Find and recover Luna 1.

One thing we can look for is out-of-equilibrium chemistry. An example is the molecular O2 level in Earth's atmosphere, which is driven by plant respiration. Absent biology it's difficult to figure out how natural processes could sustain a 20% oxygen atmosphere. And forgive me if I'm wrong about this, but as far as I know you don't generally see oxygen floating around all by itself when there's energy and plenty of other stuff it can combine with.

Another example would be Titan's abundance of methane. By no means am I claiming this is evidence of life, but out-of-equilibrium chemistry could be a "flag" for possible life or life-like activity.

Speaking of tools, nice drill ya got there...

This was interesting:


Hammer*, drill, and detachable bits! Next thing you know, they'll add pry bars and brushes!

(*I know, it's not really a hammer, but they used the word "hammer")

Good point. A hook could potentially get snagged. A tapered probe could also get wedged into something. A thin straight-sided probe may be the lowest-risk design.

Brush bristles could also get snagged in the joint between metal plates. Obviously this would all need to be designed and tested well, and only used when absolutely necessary. But I think it would be a good risk trade off, and could actually reduce risk for accomplishing the overall mission goals.

Phil: Understood. As always, it's a risk/reward tradeoff. Would the cost of adding these tools be worth the added weight and risk penalty? I think it would be. I'm not prepared to back that up with rigorous analysis, but I can point to the difficulties with TEGA as an example. It would have been really helpful to have the option pry open the doors or brush away excess dirt, and it would not have required more than a few extra ounces of equipment.

Of course the problems with TEGA were unforeseen, but that's why you should always bring some generic tools when you are far from help. You never know what you're going to need.

And: I don't in any way mean to be critical of the people who developed and built TEGA. They and the whole Phoenix team have done a magnificent job on a planet that tends to eat spacecraft. I'm just being a Monday morning quarterback here.

"KISS" is a widely used though informal engineering term, not something I just made up. It's generally considered to be a good thing, not a criticism.

My fault for using "prybar", which implies the kind of heavy steel thing you can buy at a hardware store. I meant that as an analogy, not a description. In my mind, I was really picturing something like a small screwdriver or even a dental pick.

The "brush" (again, in my imagining) would be along the lines of a large artist's brush, perhaps an inch wide.

I can't imagine those two items adding more than a few ounces. If Phoenix had them right now, they could at least attempt to "pry" open the TEGA doors, and brush away the excess soil.

A compressed air system would add considerable complexity, weight, and power demand. But a small brush would work and be really simple and lightweight.

I keep saying robotic missions should include some basic tools. These would have been really handy on Phoenix:

1. A prybar: just a metal probe, to push, pull, pry, or whatever's needed. (forcing open TEGA doors)
2. A brush for general cleaning, (like cleaning TEGA). Another brush mounted to the lander somewhere would be handy for cleaning sticky stuff out of the scoop.

These could have been permanently built-in to the RA, perhaps on the back of the scoop, no need for extra moving parts.

A hammer of some sort might be useful but would probably require a solenoid actuator, which means added complexity, weight, and power draw. Always KISS (Keep It Simple Stupid) or you're just adding problems.

Yeah, but picture the rovers running around brandishing a feather duster! And wearing a little apron!

(sorry: too much coffee, not enough sleep)

Yet another reason future missions should include some simple tools. A small pry-bar attachment for the robot arm would be really handy right now. Doesn't even need to be a moving part, it could just be a probe extending from the back of the scoop. Retract the scoop all the way and use the probe to lift the door open.

We already have a "hammer" of sorts, by touching the scoop to balky equipment and vibrating.

Spirit and Opportunity should have brought a feather duster.

Thanks, I feel slightly less stupid now!

Is that soil hanging from the edge of the scoop?
Now what would cause that? Moisture? Static cling seems unlikely.

Note for future missions: Bring a tool kit!

Seriously, a few attachments for the scoop would be really handy: A small pry-bar, something like a hammer, and a brush. Any other ideas?

imipak: Agreed, they must have tested the doors exhaustively (They did, didn't they?). It's hard to see how mere soil could jam up the doors. But if water or brine or whatever got into the hinges and froze, that could be another thing altogether.

Seems like repeatedly pushing on the doors with the scoop, allowing them to spring back over and over again, might work the ice/brine/grit out of the hinges. Or how about holding the scoop against the doors and vibrating the scoop? Just a thought.

And: Howdy all. Brilliant forum you got here!