Saturday, June 17, 2006

It is not, however, my design to dwell upon observations of this nature. I am well aware that it would be disingenuous to resolve indiscriminately the opposition of any set of men (merely because their situations might subject them to suspicion) into interested or ambitious views. Candor will oblige us to admit that even such men may be actuated by upright intentions; and it cannot be doubted that much of the opposition which has made its appearance, or may hereafter make its appearance, will spring from sources, blameless at least, if not respectable--the honest errors of minds led astray by preconceived jealousies and fears. So numerous indeed and so powerful are the causes which serve to give a false bias to the judgment, that we, upon many occasions, see wise and good men on the wrong as well as on the right side of questions of the first magnitude to society. This circumstance, if duly attended to, would furnish a lesson of moderation to those who are ever so much persuaded of their being in the right in any controversy. And a further reason for caution, in this respect, might be drawn from the reflection that we are not always sure that those who advocate the truth are influenced by purer principles than their antagonists. Ambition, avarice, personal animosity, party opposition, and many other motives not more laudable than these, are apt to operate as well upon those who support as those who oppose the right side of a question. Were there not even these inducements to moderation, nothing could be more ill-judged than that intolerant spirit which has, at all times, characterized political parties. For in politics, as in religion, it is equally absurd to aim at making proselytes by fire and sword. Heresies in either can rarely be cured by persecution.
And yet, however just these sentiments will be allowed to be, we have already sufficient indications that it will happen in this as in all former cases of great national discussion. A torrent of angry and malignant passions will be let loose. To judge from the conduct of the opposite parties, we shall be led to conclude that they will mutually hope to evince the justness of their opinions, and to increase the number of their converts by the loudness of their declamations and the bitterness of their invectives. An enlightened zeal for the energy and efficiency of government will be stigmatized as the offspring of a temper fond of despotic power and hostile to the principles of liberty. An over-scrupulous jealousy of danger to the rights of the people, which is more commonly the fault of the head than of the heart, will be represented as mere pretense and artifice, the stale bait for popularity at the expense of the public good. It will be forgotten, on the one hand, that jealousy is the usual concomitant of love, and that the noble enthusiasm of liberty is apt to be infected with a spirit of narrow and illiberal distrust. On the other hand, it will be equally forgotten that the vigor of government is essential to the security of liberty; that, in the contemplation of a sound and well-informed judgment, their interest can never be separated; and that a dangerous ambition more often lurks behind the specious mask of zeal for the rights of the people than under the forbidden appearance of zeal for the firmness and efficiency of government. History will teach us that the former has been found a much more certain road to the introduction of despotism than the latter, and that of those men who have overturned the liberties of republics, the greatest number have begun their career by paying an obsequious court to the people; commencing demagogues, and ending tyrants.

- Hamilton, Federalist Papers #1

Some things never change. The things that don't often provide an interesting perspective on the modern age.

I'm going to take a break from reading my usual political blogs, and go through the federalist papers and other interesting historical documents. If you ever get bored with yours, there is an incredible wealth of interesting stuff, from time periods ranging from the bronze age to turn of the century, available for free online.

Saturday, June 10, 2006

About those GCRs?

I've often heard of radiation given as an "insurmountable" problem to getting men to mars. Or even sending them back to the moon. And yet, people spend months at a time on the ISS, orbiting the Earth above the atmosphere. In terms of uncharged radiation, they should be getting about half of all the stuff that Mars or moon astronauts would get (The earth shields the sun about half of the time). The only type of radiation that space station astronauts aren't getting in equivalent quantities are the charged radiation due to the van Allen belts sheilding them.
The main radiation culprit fretted over are galactic cosmic rays - very energetic free nuclei that have the energy to punch through most shielding, generating secondary particles as they go. The thing that gets me though, is that nuclei are all charged. If a planetary magnetic field is enough to shield you from GCRs while in low earth orbit, why can't you just set up your own magnetic field to deflect charged radiation?

A little back of the envelope non-reletavistic highschool physics says that a magnetic field of strength B would deflect a particle in a loop of radius r = mv/qB. You would have to make the field stronger to cause tighter deflection, but the particles should loop around the field lines until they impact the magnet.

Doesn't sound so insurmountable to me. Furthermore, it sounds a whole lot more reasonable than lining your crew cabin with 10 feet of lead. You're going to have to have a reactor on your mars spacecraft to power propulsion anyway. If you take more payload weight (all the shielding), you'll have to spend a lot more energy on propulsion to accelerate. If you can save on payload weight by having lighter shielding and a magnetic shield, I wonder if it makes more sense to spend some energy on that instead?

Just an idea. Correct me if I'm wrong. (The magnet would have to be too energetic/ other serious radiation threats/ ect)