Space/Science — HabitableZone

Space/Science » in reply to You're right, Mark, it is a mess...

Digging Through For Some Key Issues Like Delta V

Getting back to DeltaV: Why is a 4.0 Km/s deltaV to EML so great when it is 3.2 to reach the Moon and 2.7 to land (which I think you need even coming from EML) and 3.6 top reach Mars and 1.0 to land. The landing delta V for Phoebos and Demos is 1.9 km/s so I would expect similar values for most asteroids since there is a big size difference in those two. Again I don't know how you calculate those values. I can only look at the trends in the numbers I have. I would guess this leveling off effect is related to a similar effect on surface gravity which is caused by being closer to the center of mass at the surface on a smaller body despite a weaker overall gravity field. You spend more energy to reach an orbital point, still have to pay some deltaV to reach another point, and still have to pay the deltaV to land. This sounds like the silliest most idiotic waste of resources I've ever heard of. To want to go there because its easy to go somewhere else from there without bothering to note that you just made the whole trip harder to obtain no resources is just stupid. EML only makes sense to me when that is the final destination because of orbital stability/positioning requirements.

You can compare the Moon and Mars agendas by clearly killing the false arguement that the Moon is a key path to Mars and then by comparing the inate value each have in their own right. The focus on the delta V issue is to kill the false arguement that the Moon is a key path to Mars. It's not the only issue, but is the key false issue that keeps raising its ugly head. Far to many people buy the arguement that we have to go back to the Moon to go to Mars rather than focusing on which is of more inate value as a target.

As far as Mars NEO detection goes you keep avoiding admitting you grossly misrepresented the context of the Mars/NEO debate. You can't build consensus by paying so little attention to others views that you totally misrepresent their arguements. You especially can't do it if the misrepresentation is intentional which I assume it wasn't, although continued evasion of admitting the error makes that appear more likely.

Setting spending priorities mean you spend more money on higher priority items and only spend 0 on items you care nothing about. It doesn't mean you spend money only on priority 1 items. NASA's relatively low priority is reflected in its low percentage alllocation. Your comment does not address the issue at all that we can address NEOs and manned missions to Mars with existing funding levels. You don't need to abandon human spaceflight to finance an orbital NEO detection system. You only need to cancel or postpone ONE robotic mission. This is simple math Ken. Anyone who can do deltaV calculations should be able to add and subtract sufficiently to understand this arguement.

Your speculation on life in comets is at odds with the scientific consensus. Your idea that comets contain detectable levels of planetary material also sounds ludicrous. How would you plan to determine that tiny fractions of comets contained elements from planets rather than blow-off from dying stars? That is not a basis for building consensus in a scientifically inclined community. Push that boat if you want, but don't claim your primary goal is building consensus.

Regards,
Mark

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