Chen, K. Joseph, McConaghy, T. Troy, Landau, Damon F., Longuski, James M., Aldrin, Buzz , "A Powered Earth-Mars Cycler with Three Synodic-Period Repeat Time,” Journal of Spacecraft and Rockets, Vol. 42, No. 5, September–October 2005, pp. 921–927.
Chen is grad student at Purdue (same as Armstrong). Landau (grad student at JPL now) Lonuski (Ph.D. advisor for Troy)
"contact light" - Aldrin was first person to talk on the moon (he says) - "Encounter with Tiber" - went to West Point, in Korean War, MIT Ph.D. (known later as "Dr. Rendezvous" later) -- sister called him "Buzzer" and that was shortened to Buzz and he legally changed it from Edwin to Buzz.
In 1983-4 he was talking about a "cycler" orbit to Mars like a bus that passes by the stops repeatedly, passing by Earth and Mars. You have to find natural paths under gravity of sun, Earth, and Mars. You can take a taxi spacecraft up and down to Mars/Earth.
Hollister considered this earlier in for Venus as "castles in space"
Aldrin "cycler" was discovered and Buzz went over to JPL to Dennis Burns and Longuski and they helped with calculations and if it would work - how long it would take (1985 classic paper)
Niehoff and Freedlander cycler - visit 1 and 2.
Around 2001 Buzz was thinking of these again but involved in space community and thinking of new ones and contacted Dennis Burns (Longuski left JPL in 1989 and became Troy's advisor). Buzz will call by teleconference - listen? Sure! Really cool... Filled up conference room... Cathy Howe (also prof on trajectories and body problems) was there. Called and described ideas and we drew sketches and Troy started to think about this....
Ended up having 7 more conferences...on cruise ship and at Pentagon and we ended up writing 2 conferenc papers and 1 journal papers.
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Questions:
[12:14] Troy McLuhan: Chen, K. Joseph, McConaghy, T. Troy, Landau, Damon F., Longuski, James M., Aldrin, Buzz , "A Powered Earth-Mars Cycler with Three Synodic-Period Repeat Time,” Journal of Spacecraft and Rockets, Vol. 42, No. 5, September–October 2005, pp. 921–927. [12:14] Troy McLuhan: http://www.troymcconaghy.com/papers/ [12:15] Rocket Sellers: what was the purpose of the paper? intellectual exercise or seeking research funding to really build such a thing?
S1L1 Ballistic Cycler Troy discovered - 158 days to Mars or vice versa... not much effort...
Not anytime soon... about Enterprise sized vehicles...
[12:16] JS Uralia: which is the most attractive and how many days is it?
Q: Which is the most attractive and how many days is it?
Less fuel and time and propellant criteria...
[12:17] Vic Michalak: I know about the Langragian points under the Earth-Moon gravity infuence - static points? --- but are these cyclers static or vary depending on the relationship between the Earth and Mars -- in other words, are they time dependent?
1.5 AU Mars and 1.0 Earth counterclockwise around sun... Cyclic trajectory leaves Earth and Mars is there when you reach it... Angle between Earth and Mars and sun will repeat every once in awhile... Turns out for Earth and Mars it takes 2 1/7 years for this angle (25 degrees as example)... Earth-Mars synodic period --- see www.damninteresting.com/?p=960
Periodic solution to the 4-body problem, but not very useful because 4-body problem is a difficult one...
[12:18] Rocket Sellers: how close to earth are the cycler paths? [12:21] Tenk Kidd: There is a simplified Aldrin Cycler animation at http://www.damninteresting.com/?p=960
[12:22] JS Uralia: I guess I meant to ask, which is the fastest cycler which doesn't require an inordinate amount of fuel, and how many days is it?
Closer to Earth you fly, the more gravity assist you get...
With the Aldrin cycle you would have to pass under the Earth's surface to sustain it, so they use 200 miles...
[12:24] Troy McLuhan: McConaghy, T. Troy, Landau, Damon F., Yam, Chit Hong, and Longuski, James, M., "Notable Two-Synodic-Period Earth-Mars Cycler," Journal of Spacecraft and Rockets, Vol. 43, No. 2, March–April 2006, pp. 456–465.
2006 paper funded by Dennis Burns -- was going to be called the McConaghy cycler but advisor thought too presumptous, so only called xxxx cycler..
[12:25] Tenk Kidd: Do cycler solutions exist for all planetary pairs? [12:25] JS Uralia: http://en.wikipedia.org/wiki/Mars_cycler says there's a 75 day cycler, is that one a big fuel burner?
"Advice to Rocket Scientists" by Longuski "Seven Secrets of How to Think Like a Rocket Scientist" by Longuski
3rd book with Massive(?) Hutu kid book about flying to Europa and finding fish, etc... with big monster...
When Longuski was working at JPL he was working on gravity-assist vehicles visiting moons around other
Crashed Galileo into Jupiter... Cassini is still going...
[12:29] Caledonia Heron: how long would a mission using this kind of cycler take? say to mars from earth?"
[12:29] JS Uralia: 146 days
Want to take less than 6 months... but do not want to use a lot of propellant
[12:30] Rocket Sellers: did you look into the costs of creating such a system? and what it would look like?
Landau looked at costs and examined all the ways to get to and from Mars --- amazing paper --- ---> Look for this
(check this)
Construction costs...propellant costs... [$10K/kg but Falcon 1 would be less]....otherwise too expensive
[12:32] Rocket Sellers: 10,000/lb [12:32] Rocket Sellers: oh i thought you said milligram [12:32] Paradox Olbers: what about cost takiing possible water in martian moons> [12:32] Rocket Sellers: ?
Easier to take off and land on Mars -- Damon did consider that to use water to create fuel.
[12:33] Paradox Olbers: into account [12:33] Paradox Olbers: for oxidizer [12:33] Paradox Olbers: but getting down to mars is costly [12:33] Paradox Olbers: martian moons are low delta-vee from earth [12:34] Rocket Sellers: zubrin
"Case for Mars" Zubrin?
[12:34] Nicholas Hawthorne: doesn't nasa have the same idea for the moon? [12:34] Rocket Sellers: or watch Martian Underground on YouTube [12:35] Nicholas Hawthorne: i mean in terms of the propellent
Actually considered --- Apollo 13 was the first case...
[12:35] Rocket Sellers: when you do these calculations , do you take the paths of asteroids and comets into account?
negligible gravity
[12:35] Nicholas Hawthorne: i mean using water to make propellent, didn't nasa think of it for the moon and mars?
[12:36] Rocket Sellers: what about collision [12:36] Paradox Olbers: Apollo 13 had just left their free-return trajectory before the explosion, but yes, able to loop around with just enuf delta-vee to return
Called "preliminary design" with only large bodies considered...
[12:36] JS Uralia: Landau and Longuski (2004) "A Reassessment of Trajectory Options for Human Missions to Mars" http://pdf.aiaa.org/preview/CDReadyMAST04_856/PV2004_5095.pdf
After taking Mars into account, then need to consider Jupiter and solar wind pressure, etc...
[12:37] Rocket Sellers: that mission to Eros was NEAR
[12:38] Storm Nordwind: What is the length of the time window available to use a cycler? In other words, how many craft could use a cycler at a time?
Probably a couple of days leeway.. maybe 5? like a wagon train...
2 1/7 years in different orbit, but same topology, and 2 1/7 years later, etc...
[12:39] Paradox Olbers: the LM tanks had been extended 20% in design to allow for enuf fuel in LM to return the CSModules "just in case" - thank goodness indeed :)
Will they ever be used? Not on first missions, but once we have low cost recurring ways to Mars, then you build these...
[12:39] Paradox Olbers: the LM tanks had been extended 20% in design to allow for enuf fuel in LM to return the CSModules "just in case" - thank goodness indeed :) [12:40] Tenk Kidd: Might it be possible to gather enough initial V from Solar Sailing to start off a Cycler? [12:41] Esme Qunhua is Online [12:41] Rocket Sellers: for a generation ship ?
Kind of question that Longuski's students like...
Like going past Mars with masses on really long cable and dipping into atmosphere and using mass to through you see Purdue faculty site...
[12:42] Paradox Olbers: Tenk, possible, but does the cycler orbits require any high-thrust corrections [beyond sail thrust]? [12:42] Archivist Llewellyn: What is going on with von Braun's idea of using a space station as a launching point to farther locations, like Mars?
Possibly device on moons of Mars --- like a merry-go-round... energy from sun... finally it detaches and goes flying to Earth...
[12:44] Paradox Olbers: Archivist, first we need a space station in a usuable interplanetary launch orbit [12:44] Paradox Olbers: not the 51degree inclination of ISS
51 degrees is to appease Russians... easiest one is your launch site...
[12:44] Paradox Olbers: we need an equatorial [12:44] Tenk Kidd: What I was thinking was the lowest possible energy requirement to initiate a Cycler, even if the time to initiation took a long interval
yes... LEO is easier... then gradually over time with solar wind or power to escape trajectory... but will take time (year or more0, so still need taxi vehicle
probably most feasible idea... but you want to be on a hyperbolic orbit, delta V with hydrazine or lOX and hydrogen, etc...
[12:45] Paradox Olbers: the 51 degree was for the russian launches - yep, troy
[12:45] JS Uralia: if we just wanted to use bodies in the solar system to send an object out of the solar system, how fast could it be accelerated?
All you need to do is escape Earth and you can use gravity assists from other planets... might take 50 years to escape, but could do it...
[12:46] Paradox Olbers: JS, whatever speed the Pluto New Horizons probe reaches [12:47] Paradox Olbers: 9 years to pluto - and nine hours thru the Pluto moon system [12:47] Alfa Roux is Online [12:47] Paradox Olbers: then it's in escape vel [12:48] Paradox Olbers: JS - i'm sure max speed would be higher for a diff probe
[12:49] Rocket Sellers: Troy do you plan to go to Mars? [12:49] Aurora Kitaj: yw [12:50] Rocket Sellers: would you bother going to the Moon?
Would to cool to go to Mars! and moon, like tourist attraction, if reasonable...
Bachelors in applied math and physics and trajectory design is application of this...
[12:50] JS Uralia: what software do you use to solve these things? Runge-Kutta?
conic sections... parabola, ellipse, etc. for preliminary design to be convinced that it could exist...
[12:51] Paradox Olbers: Steven Baxter wrote Titan - a manned trip-possible because only one way :) resupply rockets to preserve them [12:51] Archivist Llewellyn: Do you also do calculations for satellite orbital insertions? [12:51] Paradox Olbers: but i think troy prefers return option from mars or Luna [12:51] Tenk Kidd: Troy, if you were an interstellar traveller, what sort of trajectory would you design to come in and have a good close look at the Earth as you swooped by to something more interesting?
Later more sophisticated ones with solar wind and relativistic corrections for newtonian physics, plus atmosphere of Mars and Earth...
Air braking to change elliptical orbit to mostly circular orbit...
Vector additions... Jupiter...
[12:52] Paradox Olbers: i'd come in one plane of ecliptic, same direction as earth's orbital motion to lengthen time passing earth [12:53] JS Uralia: used the atmosphere to slow down? [12:53] Paradox Olbers: on plane^ [12:53] JS Uralia: that was in 2010 too, my favorite part of that movie [12:53] JS Uralia: wow like sailing
If you were coming from interstellar space you would have an approach vector --- the Earth would look like a circle -- decide at what o'clock to approach... vote... Great Wall of China or Sistine Chapel... Personally fly over home in Saskatchewan! :) but flying so fast you could only take one blurry picture...
Unlikely in plane of ecliptic...
Yes, can use atmosphere to slow down...
[12:57] JS Uralia: you already answered those, I was interacting [12:57] Paradox Olbers: ...thinking of Clarke's Starglider making a hyperbolic thru Sol system
Coming up to end of the hour...
[12:58] JS Uralia: the Jupiter atmospheric slowdown
[12:59] Tenk Kidd: I seem to remember some anomaly had been obderved in the trajectory of the Voyager probes - they are picking up speed! http://physicsworld.com/cws/article/print/20123
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