Time scale matters. Long term considerations are completely irrelevant when you won't hold a stock long enough for them to matter. Meanwhile if you're planning to buy and hold for a long time, you shouldn't be trying to time the market or making a lot of trades.

Rather than the silly argument that something is a Ponzi scheme just because one guy profits from a completely different approach to investing than you would take, recognize that it takes a peculiar skill set and effort/focus to be good at any sort of market making or other short term trading. This guy happens to have those skills and to take the effort.

Instead, we have what would, if it were an attempt at investment, be a guaranteed money loser for anyone putting in now, with a built in huge incentive for the federal government to cut back on future benefits in order to pay current benefits. That's the real Ponzi scheme.

And in the process, Social Security as it currently stands lessens ownership of capital (none of that money enables the Social Security pensioner to own even a little bit of a company or other capital), which unlike labor is not declining in value, while dumping that money in the hands of special interests who pick up public funding. Plenty to like about that scheme.

Sounds like you should have ignored what you were thinking too.

Indeed. Notice I never said anything to disagree. I didn't speak at all of DreamChaser's features which would mitigate or evade the Challenger and Columbia disasters.

Not at all. Keep in mind that Apollo 13 accident happened just prior to a propellant burn to insert the capsule in lunar orbit. The Shuttle under the same situation would have propellant on board and some sort of active rocket engine for conducting the burn (though not necessarily the Main Engines). In that situation, damage to the heat shield is still possible depending on where everything happens to be. For example, if the Shuttle is still piggy backing on the side, then the heat shield is still exposed to potential damage.

And not much of a reason to care either since the heat shield has been inspected on the ground. But I suppose we could stick a couple of cameras on the service module to image the heat shield, should this ever become a problem.

So what? Lockheed Martin would spend more than that, if we let them. The cost of their projects tend to be sized to the available funding. None of the other capsule builders have this sort of problem.

You can "shield" your engines just by not pointing the exhaust directly at the target you're trying to sneak up on.

"Probably very hot" is considerable fail right there. For example, the exhaust temperature of chemical rockets drops considerably as it passes through the "throttle", a constriction and subsequent expansion which converts most of the thermal energy of the exhaust into kinetic motion. So the exhaust as viewed from the side is vastly cooler than if you're looking directly down the throttle to the burn chamber.

Further, the "shielding" that everyone talks about just isn't that heavy. The bell of a chemical rocket already acts as a simple shield and one can put a lightweight (as in lighter than the bell's mass which is already pretty negligible) shroud outside that to mask the heat radiated from the bell.

And of course, there's the mass driver approach which allows one to decelerate in line with a target and produce no notable heat signature while spewing projectiles in a militarily useful direction.

If you're going to bring that up, please remember that the above observation is completely irrelevant since spacecraft can move a lot faster than the Voyager spacecraft, are trying to hide, and aren't deliberately broadcasting signals at the enemy to pick up.

A wealthy idiot who probably made more in ten years trading stocks than you'll make in several lifetimes. If the "idiot" achieves by their actions a considerable gain (be it money or not), then maybe you should reconsider whether the term is appropriate.

More like 10 per day. Banker holidays.

For example, the author asserts that "stealth efficiency" of rockets (in an equation he uses) are "0.0". But you can do better than that (I'd say near 1.0 to be honest) merely by not pointing your rocket directly at a detector.

Unless you aren't firing your engines. Or the enemy can't detect the output of your engines (eg, certain light based, railgun-style propulsion, and "propellantless" drives) or maneuver tricks that don't involve thrust (such as slings and gravity assists).

And the linked article you refer to doesn't understand the idea of directed power. If an enemy starship that is trying to sneak up on you has their terawatt engines firing in your direction, it's because they're trying to cut your ship in half. When engines aren't pointed at you, they have a much lower energy signature and aren't detectable all the way out to Alpha Centauri (though obviously a torchship is going to be pretty easy to detect just the same). Similarly, the two Voyager spacecraft have easily detectable signals because those signals are directed by a high gain parabolic antenna at Earth, because the signal has a narrow bandwidth, and because there's a huge dish at Earth to pick up the signal.

On that last point, there's the matter of detecting signals. The problem here is that you need a lot of surface area and scanning to get the sort of sensitivity discussed in the article. You want to hear a 20 watt narrow bandwidth signal at 120 AU? You need a 70 meter dish and extremely low noise sensor or equivalent in alien technology. This stuff has mass and doesn't handle acceleration well. So now, your system is split into at least two parts, a delicate sensor side and the blow-them-up side.

And if it's coming in fast enough, even the flak can kill you.

Except that the federal government doesn't have any such "right". At best, the federal government has the legal authority to regulate interstate commerce, but not necessarily intrastate commerce, like Iowa's regulation of car dealerships. You have to show violation first. And I don't buy that is actually happening here.

One can always make a sufficiently adventurous court decision, but that approach has a lot of blowback, more likely to cause trouble than to fix it especially once the adventurers start dealing with the inconvenient laws that help keep US citizens mostly free. The commerce clause in particular is a far too flexible means as it is of doing whatever the central government wants at the expense of everyone else. You don't really want a court to run with that just to break the power of Iowan car dealerships.

Why are you posting then?

We can look at Apollo to see what human-level exploration and research looks like. I find it disingenuous to equate human-level exploration with no exploration at all.

That's why sky divers use them only for emergencies. Pardon my sarcasm. And you're not "flying" with parachutes, but landing with them - a place where they have quite a bit of success and have turned out to be quite reliable.

To the contrary, in the Challenger accident, two things would have been different. First, the capsule would have been on top of the vehicle. Second, it would have a launch abort system attached. That combination would have made the accident survivable.

The same goes for the Columbia accident. The capsule would not have been situated on the side of the launch vehicle where it could receive an impact and hence would not have had said basketball sized hole in the vehicle.

Finally, it's worth noting that NASA didn't have a need for a vehicle larger than a big capsule. They never had more than seven people in the crew. And payloads were no more massive and only a little bit bigger in width than the current Delta IV Heavy and the 80's Titan IV could handle.

A big part of the reason I'm not convinced is because of how much boosters of unmanned-only exaggerate the capabilities of such machines. There's no current machine that can beat a pressure-suited expert on the ground. And merely having better sensory equipment (when that actually is the case) doesn't mean a better ability at spotting the unusual.

In the meantime, the current desultory effort at studying Mars, means we'll lose at least a whole generation of researchers long before we get to human-level science acquisition on Mars.

Depends how important you think it is to do that. If you're willing to spend a billion dollars, then that's a strong indication to me that you should be interested in the advantages of having a human on site. If you don't think it's that valuable, then it isn't that valuable with humans either.

The problem is that the operators remain on Earth not Mars. There's a hard lag time which can be over an hour one way.

Move around on the surface of Mars and examine objects with lag time to a human operator of about a tenth of a second.