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Comment point of no return (Score 1) 540

How is it possible to demonstrate that there are any sort of psychological evaluations that can determine if a potential Mars astronaut is actually ready for this sort of mission? This mission promises to set up a sustainable and growing community, but for an individual astronaut, there is also going to be a complete and final separation from damn-near everyone they know, and everything they've known, and all the millions of things anyone has come to take for granted after living on Earth for at least 25 years. So there is a sense in which this is comparable to a suicide mission, because of the separation. We also know from survivors of suicide attempts that if there is time for contemplation after the point of no return, there is nearly universally regret of the attempt. Those who jump off a bridge, and survive, nearly universally report that mid-air they had immediate regrets of jumping. How can it be possible to ensure that, once the astronauts are past the point of no return in the mission, there won't be a similar feeling of regret?

Comment Space for growing food? (Score 5, Interesting) 540

Your FAQ, in the "sustainability" question, states

The first four will also be carrying a device similar to a portable greenhouse, that will allow them to grow their own food.

If we take 2000 calories per day as a baseline human need, that's 730,000 calories per [Earth] year, or about 3 million calories per Earth year per four-person crew, and the total need will grow by 3 million calories per Earth year every two years as more missions arrive. The diet would need to be varied, both to guard against catastrophic crop failure and to provide an appropriate spectrum of nutrients, and a reasonable estimate (e.g. based on a combination of corn, beans, and squash) suggests that 1 acre on Earth can provide such 3 million calories. But Mars gets, on average, only about 44% of the insolation as Earth does, so the first-order estimate suggests you'd need about 2.3 acres per mission-load of astronauts to grow a subsistence diet. This presumes that radiation won't negatively impact the crops, that the yield throughout the Mars growing season scales comparable to the Earth's, that your soil is comparable to Earth's, and many more things. You'll also need enough additional carbon and water to make the non-edible parts of the plants and soil, and you'll need to make sure there exists a suitable microbial community to decompose crop waste and turn it back into a useable food-growing medium (i.e. compost).

I don't see in your concept drawing anything that approaches the size of land that would be needed to come anywhere close to such sustainable food production. Do you even have a back-of-the-envelope plan for sustainable food production, or is the bulk of the astronauts' calories going to need to come in perpetuity from the Earth?

Comment Test score growth: don't trust it (Score 3, Interesting) 343

I realize TFA is more like the author's off-the-cuff musings and less like a rigorous study, but it does recommend looking at test score growth, and in the process fails to mention something that's both nearly obvious but almost always overlooked when discussing test score growth. When test scores grow, one is by definition comparing the scores that one group of students took on one test to the scores that another group of students got on a different test. With that in mind, there are 5 principal ways that test scores can "go up":

1. students cheat on the second test
2. the second test is easier
3. students who score low on the first test don't take the second test
4. students, who score high on the second test, were added to the testing group but did not take the first test
5. more individual students score better on the second test than perform worse on the second test

Cheating does happen, but it's probably rare. Tests can be psychologically validated to ensure constant difficulty, but this isn't done as often as it should. Nevertheless, #3 is by far the most common and least talked about way for test scores (particularly relative test scores) to improve. TFA recommends looking at the relative standing of a schools 2nd graders and 5th or 6th graders. We'd like to think that the students are being educated so successfully that their performance improves, but anyone making such a claim ought to be required to (rigorously and mathematically) prove that changes in the student population are not the primary cause. There is pretty good evidence, for example, that the high-profile improvement in the charter school that Michelle Rhee worked at was rather effective at "counseling out" the consistently low scoring students to have apparent test score gains that had little to do with their instructional program. I can well imagine the administrative staff of a school "working with" the parents to help find a school that's "a better match" to their kid's "unique learning style."

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