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#776 Re: Human missions » Mars Colonization Program - Mission 1: Your Comments? » 2005-06-01 00:13:15
It does make sense to use a cycler to deliver and return large cargoes between Earth and Mars as it comes down to efficiency. And since most cargoes will be going just one way and that is too mars the cycler can be refueled from the asteroid belts C type asteroids and return practically empty. Of course in Earth vicinity it can pick up the cargoes heading to Mars and the next colonists.
Still it all comes down to the goverment or goverments that has the political and financial will to actually go with a Mars colonisation plan.
Grypd, if a cycler is tracking a free return orbit (more or less) being "full" or empty" would seem largely irrelevant. Mars orbital capture and landing will require delta V - - going back to Earth's vicinity will be "free" - - no?
Solar thermal rockets (for example) can be used to incrementally adjust trajectories to remain "free return" meaning fuel requirements are minimal.
As far as re-using rockets, what about landing RL-10 propelled payloads on the Mars surface, refurbish the engines and send them back to Earth?
Ummm, free-return is not "free" by any means, free is simply referring that you are letting the suns' gravity do alot of the work so that you can depart from Mars at any time without any extra fuel compared to regular HTO. You still have to burn considerable fuel to leave Mars orbit.
No Bill, the vehicle used on the Mars-to-Mars Orbit and back must be reuseable AND Mars Colonization Program - Mission 1: Your Comments?] stationed on Mars. This is the only way to sufficently leverage Martian propellant production in order to hold down the per-sortie mass of each cargo trip.
By http://courses.ncssm.edu/math/TCMConf/T … t.pdf]free return I mean a trajectory that arrives in the vicinity of Mars and then Earth using gravity assists only. Such creatures exist but are difficult for Mars because of certain peculiarities in the Mars orbit. Aldrin cycler is another term that is used.
Tiny adjustments can be made by solar ion or solar thermal during the long passages between Earth and Mars and at Mars the colony simply does not stop, or even slow down - - one way settlers re-enter small capsules for aerobraking, aerocapture and landing while the more luxurious mother ship keeps going, with no aerobraking.
Perhaps the mother ship alters its course to stop at an Earth-Moon LaGrange point for another set of colonists. This way, tiny capsules (t/Space sized) can carry settlers from Earth to LEO/L1 and the colony ship and those same capsules are used to land on Mars while the six month journey is made feasible by living on board a larger ship.
With a genuine free return trajectory, the fuel needs are minimal to none. Mars Direct free returns are chosen based on propulsion failure.
= = =
The linked exercise is to design a lunar free return, defined as the ability to return from the Moon without any propulsive engines burns after the trans-lunar insertion burn.
A Mars free return would return a spacecraft to Earth, after a Mars fly-by without propulsive engine burns.
= = =
A http://news.uns.purdue.edu/UNS/html4eve … .html]2014 Mars free return trajectory that assumes main engine failure, thus very little propulsion is needed so that attitude control thrusters are sufficient.
Longuski and graduate student Masataka Okutsu discovered that the safest route to take would be one that permitted a quick return trip, via Venus, in case of an accident that forced the Mars landing to be aborted. The Martian gravity would bend the spacecraft's trajectory, hurtling it toward Venus, where another gravity assist would guide the ship to Earth. Because of the gravity-assisted trajectories, the spacecraft could make the return trip with only minor attitude adjustments from small thrusters, even if its main engine were disabled, Longuski says.
Using solar thermal, doing continuing burns between Earth & Mars, fuel consumption would be miniscule.
Edited By BWhite on 1117607050
#777 Re: Human missions » Mars Colonization Program - Mission 1: Your Comments? » 2005-05-31 18:05:46
It does make sense to use a cycler to deliver and return large cargoes between Earth and Mars as it comes down to efficiency. And since most cargoes will be going just one way and that is too mars the cycler can be refueled from the asteroid belts C type asteroids and return practically empty. Of course in Earth vicinity it can pick up the cargoes heading to Mars and the next colonists.
Still it all comes down to the goverment or goverments that has the political and financial will to actually go with a Mars colonisation plan.
Grypd, if a cycler is tracking a free return orbit (more or less) being "full" or empty" would seem largely irrelevant. Mars orbital capture and landing will require delta V - - going back to Earth's vicinity will be "free" - - no?
Solar thermal rockets (for example) can be used to incrementally adjust trajectories to remain "free return" meaning fuel requirements are minimal.
As far as re-using rockets, what about landing RL-10 propelled payloads on the Mars surface, refurbish the engines and send them back to Earth?
Edited By BWhite on 1117584524
#778 Re: Not So Free Chat » Did Robert Zubrin Design A 3 Player Chess Game? - Saw it in a magazine » 2005-05-31 16:25:07
Google:
http://www.google.com/search?as_q=Zubri … ges]Zubrin (Not) Robert
#779 Re: Not So Free Chat » Did Robert Zubrin Design A 3 Player Chess Game? - Saw it in a magazine » 2005-05-31 16:19:36
http://www.chessvariants.org/multiplaye … pdf]Patent link
I will bet a dollar its our same Dr. Zubrin.
= = =
Question: Is ANYONE named Zubrin except Robert?
Bill White? I am the mayor of Houston not to mention David White, Robert White, Charles White etc. . .
Is there anyone else named Zubrin? In the world? I suspect its one of those names that got "created" at Ellis Island.
Edited By BWhite on 1117578192
#780 Re: Not So Free Chat » Did Robert Zubrin Design A 3 Player Chess Game? - Saw it in a magazine » 2005-05-31 16:15:54
Another version, not Zubrin's.
http://www.math.tau.ac.il/~gvili/worksh … p/Req.html
Hmmm. . .
1974? I believe I subscribed to S&T back then. :;):
#781 Re: Not So Free Chat » Did Robert Zubrin Design A 3 Player Chess Game? - Saw it in a magazine » 2005-05-31 16:06:43
google is great
http://www.chessvariants.org/multiplaye … ...ss.html
Send him an e-mail and ask. :;):
= = =
http://www.ee0r.com/tri-chess/]Martian Chess & Go
Edited By BWhite on 1117577429
#782 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 13:14:04
http://www.andrewsullivan.com/index.php … 282]Andrew Sullivan:
But we can parse what we know and the empirical evidence points to widespread abuse and torture of detainees in every field of operation. The patterns of abuse were very similar - geared toward humiliation of Muslims through nakedness, use of dogs, sexual shame, etc. - and they crop up everywhere. Abu Ghraib was "Gitmoized" and techniques approved for the CIA in cases of al Qaeda big-shots "migrated" throughout the system, as the government reports delicately put it. The memos lowering U.S. moral standards were part of the Iraq war-plan, even though no observers would dispute that the Iraq war was covered by the Geneva Conventions in every respect. The evidence of abuse - far greater than any infractions in domestic U.S. jails - is now simply indisputable. It is telling, it seems to me, that the administration's essential defense now is that all the abuse was a result of military insubordination, i.e. that it was not in control of its own soldiers. So you get to pick between a deliberate legal choice of abuse and incompetence on an epic scale. But if it was incompetence, why have none of the architects been fired? In fact, they've been rewarded.
Heh!
And Cheney is outraged. We aren't as bad as Hitler, so stop whining.
#783 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 13:03:28
http://instapundit.com/archives/023326.php]Glenn Reynolds is a very pro-Bush blogger. Read his links about torture.
#784 Re: Human missions » Mars Colonization Program - Mission 1: Your Comments? » 2005-05-31 12:50:32
If cargo payloads track a weak stability boundary trajectory (the so called "Lo Roads") no exotic propulsion is needed. Just a supply chain pipeline filled with modules. Change the ratio of "LEO mass" --> "Mars delivered mass" from 1/5 to 1/2 or better and the capital expense of exotic propulsion may not be justified at least for cargo.
The slow boat to Mars will replace the slow boat to China in story and song.
Earth to LEO remains the big price component, not LEO to Mars, at least for cargo.
Edited By BWhite on 1117565934
#785 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 12:18:06
"The new ruler must determine all the injuries that he will need to inflict. He must inflict them once and for all."
Wimpy Romans beget quagmires.
#786 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 11:50:53
Road trip movies can be so lame. . .
Unless they are done well. Good luck!
#787 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 11:30:34
Dude, who are the administrators, and who are the trolls?
I'm obviously wearing the wrong underwear today if I have to ask.
Dude, we are discussing one the best movies, evar.
That and how the guy who pushed for freedom fries has http://www.theage.com.au/news/World/Fri … e]recanted.
#788 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 11:21:20
Elwood: Oh no.
Jake: What the #### was that?
Elwood: The motor. We've thrown a rod.
Jake: Is that serious?
Elwood: Yup.
= = =
Jake: You were outside, I was inside. You were supposed to keep in touch with the band. I kept asking you if we were gonna play again.
Elwood: What was I gonna do? Take away your only hope? Take away the very thing that kept you going in there? I took the liberty of bullshitting you.
Jake: You lied to me.
Elwood: Wasn't lies, it was just... bullshit.
Edited By BWhite on 1117560133
#789 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 10:52:44
Elwood: It's got a cop motor, a 440 cubic inch plant, it's got cop tires, cop suspensions, cop shocks. It's a model made before catalytic converters so it'll run good on regular gas. What do you say, is it the new Bluesmobile or what?
Jake: Fix the cigarette lighter.
#790 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 10:49:57
"We're on a mission from God."
Context is everything:
Jake: First you trade the Cadillac for a microphone. Then you lie to me about the band. Now you're gonna put me right back in the joint.
Elwood: They're not gonna catch us. We're on a mission from God.
I've always liked this one:
Elwood: It's 106 miles to Chicago, we've got a full tank of gas, half a pack of cigarettes, it's dark and we're wearing sunglasses.
Jake: Hit it.
#791 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 10:37:27
I mean if we have to have fascists, why not inept fascists? What could be better?
Effecient communists. You'll understand once you get to the gulag.
Blues Brothers may be too old of a movie for all the young people here but its still full of great lines.
"Nazis? I hate Nazis, especially Illinois Nazis"
Edited By BWhite on 1117557464
#792 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 09:42:38
Heh! I need to be more sanguine.
Bush and Cheney being the posterchildren for fascism is actually a very good thing. I mean if we have to have fascists, why not inept fascists? What could be better?
#793 Re: Not So Free Chat » Political Potpourri V - Continued from previous » 2005-05-31 09:29:50
Nah, you missed the point.
Even Epcot in Orlando has an exhibit on the expectations game. Put you hand in cold water then luke warm water. The luke warm water seems HOT, right?
Compare Cheney to Hitler and what? Voila! He's dang near Florence Nightingale. 
Of course, Cheney isn't Hitler but by making the comparison his very real failings pale to insignificance. Me? Compared to the true commies, I would appear to be an Ayn Rand loving Uncle Milty wannabe!
= = =
The biggest problem with Gitmo is that we get NO BENEFIT from running it. Being nasty when necessary is, well, necessary.
Being nasty for the sheer pleasure of being nasty is inept and stupid.
= = =
Actually, Gitmo and Abu Ghraib happened (I believe) because our leaders are in over their heads and are making up plays as they go along.
The Israelis learned long ago that sexual humiliation is a lousy method of interrograton, it just doesn't work. Read my original post - - I very strongly believe we have garnered almost ZERO useful intelligence from the folks at Gitmo.
And now we have a prison full of low level operatives and some innocents and we are stuck being unable to admit error.
Edited By BWhite on 1117553941
#794 Re: Human missions » Mars Colonization Program - Mission 1: Your Comments? » 2005-05-31 09:02:22
If we cut to the quick, I mostly agree with GCNRevenger.
That said, if Mars settlement becomes a race to spread selfish memes (will English or Mandarin or Hindi be the dominant language in the solar system 500 years from now?) Terran people may well voluntarily pay to help support Martian settlers.
#795 Re: Not So Free Chat » Apropos of Nothing *4* » 2005-05-31 08:55:20
well, I still don't understand why men have nipples.
So much for "intelligent design".
Here is a more serious http://www.heartcenteronline.com/myhear … 306]kludge If we were intelligently designed, I want to file a claim under the warranty. ???
Building on earlier research, the Mayo Clinic researchers discovered a defect on a gene called RyR2 that may contribute to electrical problems in the heart. When these occur, the person may experience a brief abnormal heart rhythm, or arrhythmia, and faint momentarily.
If this occurs on the land, the person may fall and suffer minor bruising. While exploring the reason for fainting with a physician, the patient may eventually be diagnosed with a heart condition. However, even a brief episode of fainting while in the water may be fatal or cause a near-drowning accident that results in serious injury.
Edited By BWhite on 1117571875
#796 Re: Not So Free Chat » Empire vs Rebel Alliance » 2005-05-27 20:33:42
If this was noted above, my apologies.
Elsewhere in blog-o-land people are starting to notice that the Jedi use blue swords and the Sith use red swords. I mean come on, was George Lucas that transparent?
People like Orson Scott Card.
I did read a marvelous snarky comment though, to the effect that Orson Scott Card was a good writer until he went all "Bobby Fischer on us"
Don't know whether to agree or disagree but "going Bobby Fischer" needs to be added to our vernacular.
IMHO, as always.
= = =
Maybe going http://www.hatrack.com/research/questio … html]Bobby Fischer is kind:
With nut cases like that actually in power, why in the world would you want to attack the utterly powerless religious right?
= = =
http://www.dailykos.com/comments/2005/5 … 4/21#21]Ha! Ha! Ha!
Edited By BWhite on 1117248800
#797 Re: Not So Free Chat » Apropos of Nothing *4* » 2005-05-27 19:25:44
http://www.northjersey.com/page.php?qst … dnFlZUVFeX
kz]Buzz Aldrin says:
Feelings? Girls have feelings. Boys do things. :;):
#798 Re: Science, Technology, and Astronomy » UCS Warning on Weaponization of Space » 2005-05-27 15:32:38
merely sets the US up for a military disaster, IMHO, as always.
*The U.S. always faces military disasters? How did we become the most powerful nation on Earth then?
Bill, I thought you were willing to take a "wait and see" approach. ?
But it seems futile all the way around (comment directed towards these situations, not directed at you).
--Cindy
Cindy, some people (not necessarily here) "sell" weapons in space as a substitute for sending our soldiers into harms' way.
=THAT= attitude is very, very dangerous.
Such platforms may indeed be useful. No argument from me.
More useful than another division of Marines? More useful than better armor for our troops and better benefits for our soldiers and their families? Today, retaining mid level officers (captains & majors) is becoming a huge problem. Money spent on "rods from God" is money that cannot be spent keeping the families of our essential officer corps happy. If our infantry is hollow, space weapons won't be a successful substitute.
Tax the top 1% a little bit more and maybe we can buy both. :;):
Edited By BWhite on 1117229684
#799 Re: Science, Technology, and Astronomy » UCS Warning on Weaponization of Space » 2005-05-27 14:49:13
Again, "space based weapons" encompasses all sorts of things. It can mean satellites equipped with ASAT countermeasures as much as orbiting lasers and the rod of God.
ALAA, Automated Laser Armaments Array, that's what we'll call it, keeping with the whole deity theme.
Anyway, equipping our satellites with ASAT defenses is only prudent, it won't be long before those assets are at substantial risk. But once we've done that, why not put offensive weapons up? It's not as though we're talking about putting up a giant cannon right away and waving it around, ASAT defenses are the first order of business. Once they're in place, the door is open.
Besides, let our enemies try to keep up. Let them become dependent on their technology. That much easier to beat them if we can defend ours while denying them theirs.
Wow, I pretty much agree with this.
Like I said before, I have few moral or ethical qualms with space based weapons. I just see a whole lot of people advocating trillion dollar systems that might not actually accomplish anything useful.
If we are unable or unwilling to get our boots muddy "rods from God" won't help. If we are good at getting our boots muddy, rods from God are not really necessary.
Selling rods from God as an alternative to "muddy (& bloody) boots" merely sets the US up for a military disaster, IMHO, as always.
There was nothing wrong with the Maginot Line EXCEPT that the French relied upon it to feel secure. If we come to believe space weapons can save us from the pain of infantry deaths we WILL suffer a France 1940-like defeat.
Therefore more armor for our Humvees will be a better value than ground strike orbital weapons.
Edited By BWhite on 1117227124
#800 Re: Science, Technology, and Astronomy » UCS Warning on Weaponization of Space » 2005-05-27 14:41:05
http://www.sfgate.com/cgi-bin/article.c … DTL]Timely, no?
40,000 more Marine riflemen are a more pressing need, today, than rods from God.
Technology to defend and replace surveillance sats and com sats if we lose ours? Sure I can accept that. Bunker busters? There are many more important needs that should come first.