Major New Planetary Mission (?), Rumor at another site Options

[GregM]

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[Guest_BruceMoomaw_*]

NASA is talking now about allying with the ESA on the Mars sample return -- but "relatively inexpensive" is not a phrase that comes to mind in connection with that one. If this rumor is true (and I'm extremely skeptical): maybe they're planning a multi-nation collaboration on Europa Orbiter, including a lander?

[djellison]

It all sounds very exciting, but there's no money for it.

I wouldnt call them the 'enemy' in any way shape or form. Certainly not for me anyway.

Doug

[hendric]

Maybe a Venus lander/blimp? Venus has the advantage of a quick time-to-payoff. Plus, other than the high-temp electronics , it should be a relatively easy planet to land on, ie nice constant atmo, close to Sun, Venus Express will be in orbit (does it have the same relay capability as MEx?), etc.

[GregM]

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[tty]

How about a near-earth asteroid orbit modification demonstration mission? If using the "gravity tug" concept it would be relatively cheap, it would be dramatic at first (though rather boring in the long run), and it would have a quite decent scientific payoff as well. A "gravity tug" must be fairly heavy, so it could carry a good science payload, and since it would literally be hanging around in more or less the same place close to the asteroid for years a very close study of it would be possible.

tty

[Guest_AlexBlackwell_*]

NASA is talking now about allying with the ESA on the Mars sample return -- but "relatively inexpensive" is not a phrase that comes to mind in connection with that one. If this rumor is true (and I'm extremely skeptical): maybe they're planning a multi-nation collaboration on Europa Orbiter, including a lander?

I'm skeptical as well. Not only is it unlikely that, assuming the rumor has any validity, a "huge profile showcase mission being planned" would be simultaneously "inspiring," "relatively inexpensive," though "involv[e] ESA and the Japanese," the only real reason for NASA to bring in international partners to such an endeavor would be to spread the cost and risk. If this rumored mission is so cheap, then that wouldn't really be necessary, would it?

Frankly, this rumor sounds like the buzz that preceded JIMO. Indeed, some of phrasing and locutions used by "Flighstar" are eerily similar (viz., "kept very secret with some guys at the top," "inspiring," "showcase mission," etc.) to what I recall reading when JIMO was unveiled. If that's the mission "Flightstar" is referring to, maybe someone should tell him/her to tell his/her "friend in the industry" that the mission was cancelled.

Having said that, though, I agree that international collaboration is probably the only way to save Europa Orbiter at this juncture.

[JRehling]

Frankly, this rumor sounds like the buzz that preceded JIMO. Indeed, some of phrasing and locutions used by "Flighstar" are eerily similar (viz., "kept very secret with some guys at the top," "inspiring," "showcase mission," etc.) to what I recall reading when JIMO was unveiled. If that's the mission "Flightstar" is referring to, maybe someone should tell him/her to tell his/her "friend in the industry" that the mission was cancelled.

I also seriously wonder if this is an "echo" of the JIMO buzz, although it would speak poorly of the whisper channel that was so far behind the times.

If this rumor has any basis (and most don't), I would say the most-likely-case is some kind of lunar gambit which is perhaps as poorly conceived as JIMO, or is a proposed follow-on to LRO, or is actually based on LRO itself. Some sort of low-orbit or surface base that served as a sort of lunar webcam might be affordable and, in someone's opinion, fit the bill of what was described here.

I can hardly think of a Venus or Mars mission that would fit the bill, with airplanes coming closest.

In any rumor-guessing contest, I would always, though, nominate "no basis in fact whatsoever" as the odds-on favorite.

[GregM]

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[Guest_BruceMoomaw_*]

Well, they keep talking about it. An ESA person has confirmed it - and passed some literature on to others there. Some sort of plan does seem to exist. Some hint at the idea of harnessing an asteroid and bringing it into Earth orbit. I would think that putting a second moon in the sky would qualify as groundbreaking!

How in the world would they do THAT cheaply -- and who in their right mind would trust them to do it at all?

[Guest_AlexBlackwell_*]

Well, they keep talking about it...Terms like "bloody amazing", and that it will be "worth the wait" are being used who have seen the concept. So, I must conclude that there is something out there.

Okay, since you put it that way, the rumor must be true.

BTW, where were you when I needed to unload some real estate in the Everglades?

Seriously, though, I've seen too many of these "rumors" over the years, so I'll wait for any press conference before getting excited.

[JRehling]

Well, they keep talking about it. An ESA person has confirmed it - and passed some literature on to others there. Some sort of plan does seem to exist. Some hint at the idea of harnessing an asteroid and bringing it into Earth orbit. I would think that putting a second moon in the sky would qualify as groundbreaking!

Bringing an 8km asteroid within 800km of the Earth would produce an object in the sky with the same angular diameter as the Moon. That prospect would have a number of characteristics:

1) It would be breathtaking.
2) It would enable some very good science, as huge telescopes scanned the object in great detail.
3) It would be terrifying and would produce a small but nonzero risk of a species-ending disaster.
4) It would rightly be perceived as a military threat by the enemies of the US, yet would also be part of the spectrum of responses that another nation (like China) could one day bring to bear against the US.
5) Given a long enough lead time, it is perhaps feasible, although not necessarily with an asteroid as large as 8km. Chaos being what it is, a small initial delta-v might produce a large translation of some eventual encounter between Earth and an existing NEO.
6) That would be a flyby, not orbit, if the body were of substantial size. If it is very small, then it would not be a large feature in the sky.
7) Plan B would smash the NEO into the Moon, which would possibly create dangerous secondary impacts on Earth, and might even pollute Earth orbital space with debris rendering many orbital projects permanently ruined.

[ljk4-1]

Bringing an 8km asteroid within 800km of the Earth would produce an object in the sky with the same angular diameter as the Moon. That prospect would have a number of characteristics:

1) It would be breathtaking.
2) It would enable some very good science, as huge telescopes scanned the object in great detail.
3) It would be terrifying and would produce a small but nonzero risk of a species-ending disaster.
4) It would rightly be perceived as a military threat by the enemies of the US, yet would also be part of the spectrum of responses that another nation (like China) could one day bring to bear against the US.
5) Given a long enough lead time, it is perhaps feasible, although not necessarily with an asteroid as large as 8km. Chaos being what it is, a small initial delta-v might produce a large translation of some eventual encounter between Earth and an existing NEO.
6) That would be a flyby, not orbit, if the body were of substantial size. If it is very small, then it would not be a large feature in the sky.
7) Plan B would smash the NEO into the Moon, which would possibly create dangerous secondary impacts on Earth, and might even pollute Earth orbital space with debris rendering many orbital projects permanently ruined.

It would need to be mined right away to start our space infrastructure, which would
also reduce its size and therefore its danger to Earth.

I also had this crazy thought of someone using this space rock as the ultimate
(though suicidal) threat. Ever read Robert Forward's Martian Rainbow?

[helvick]

Bringing an 8km asteroid within 800km of the Earth would produce an object in the sky with the same angular diameter as the Moon. That prospect would have a number of characteristics:

Ignoring all other problems, and there are many.

Taking a 1500kg/m^3 density as a pure guess and for the sake of argument assume that this would be an 8kmx2km approximately cylindrical rock pile. It would have a mass of around 37,500 million tons.

To impart a delta v of 1m/sec to that requires the equivalent of 10 kilotons of TNT, or 6700 first stage Saturn 5 engines in parallel.

With a typical current Ion drive, Isp ~ 30kN s/kg, we would need ~1.2million tons of fuel. VASIMR designs if proven in flight should get Isp ~300kn s/kg and would reduce that to around 120 thousand tons.

And that's just for a total 1m/sec delta v.

How exactly would that be done cheaply?

[Bob Shaw]

Ignoring all other problems, and there are many.

Taking a 1500kg/m^3 density as a pure guess and for the sake of argument assume that this would be an 8kmx2km approximately cylindrical rock pile. It would have a mass of around 37,500 million tons.

To impart a delta v of 1m/sec to that requires the equivalent of 10 kilotons of TNT, or 6700 first stage Saturn 5 engines in parallel.

With a typical current Ion drive, Isp ~ 30kN s/kg, we would need ~1.2million tons of fuel. VASIMR designs if proven in flight should get Isp ~300kn s/kg and would reduce that to around 120 thousand tons.

And that's just for a total 1m/sec delta v.

How exactly would that be done cheaply?

Using a gravitational tractor to gently nudge a threatening NEO into a non-Earth-intersecting (at least for a while) path is one thing; braking it into orbit is quite another. If it's a matter of saving the earth, then budgets might become available, but...

...just don't send any squid!

Bob Shaw