Talk:Interplanetary Transport Network

Statements needing clarification and correction

I take issue with "As it turns out, it is very easy to transit from a path leading to the point to one leading back out. This makes sense, since the orbit is unstable, which implies one will eventually end up on one of the outbound paths after spending no energy at all. However, with careful calculation, one can pick which outbound path one wants. This turned out to be useful, as many of these paths lead to some interesting points in space, such as the Earth's Moon or the Galilean moons of Jupiter." The Ross Koon Lo Marsden paper cited talks about movement between Jovian moons after a probe has already been inserted into Jupiter's system. Jupiter - Galilean moons have a large mass parameter so travel between moons along WSBs is possible. But the Sun - Earth mass parameter is tiny. There are no WSBs extend from Sun Earth Lagrange 2 to Jupiter or even Mars. At this point the assertion is merely vague. But a later portion makes it clear the writer believes the WSBs will arry us anywhere from SEL2: "As a result, for the cost of reaching the Earth–Sun L2 point, which is rather low energy value, one can travel to a huge number of very interesting points for a little or no additional fuel cost. The transfers are so low-energy that they make travel to almost any point in the Solar System possible." Writing about travel between earth and Mars, Belbruno's colleague Toppotu notes " Unfortunately, the R3BPs involved in this study, due to their small mass parameters, do not allow the manifolds to develop far enough to approach each other; hence in this case the manifolds do not intersect even in the configuration space." WSBs won't take us from earth to Mars, much less from earth to Jupiter. - HopDavid 6 January 2016‎

External Links

The mention of the Belbruno paper mentioning the four-body problem from invariant manifolds is a broken reference and a broken link as well. Does anyone have a copy of this hiding somewhere that they can either reference or upload so they can reference it? Thanks and regards. -- User:Digemedi 19:19, 31.30.2009 —Preceding undated comment added 02:20, 1 April 2009 (UTC).

Spelling

Is this the correct spelling? Is it really "superhiway" instead of "superhighway"? I find no Google hits with this spelling. -- Zoe

I looked in the article quoted, and they used "superhighway," so I moved it. - Montréalais

• POSSIBLE COPYVIO From http://www.nsf.gov/news/news_summ.jsp?cntn_id=104423&org=olpa&from=news, the text is identical to that of "Mathematics Unites The Heavens And The Atom" Space Daily, 28 Sep 2005
  • Publications of United States Government agencies are in the public domain. Kurt Weber 19:51, 8 January 2006 (UTC)

Chaos theory?

How exactly does chaos theory predict these orbit transfers? That line assuming it is not total nonsense shoudl be explained and cited. Dalf | Talk 06:20, 4 August 2006 (UTC)

Please excuse my spelling for my following comment... I don't entirely disagree with the previous comment, however, a three body system is in most cases chaotic. Our own solar system, not to mention other planetary systems, etc., is more than a three body system. —Preceding unsigned comment added by 69.228.207.81 (talk) 08:37, 11 June 2008 (UTC)

The established chaotic nature of n-body gravitational systems suggests the possibility that extremely high-gain amplification of relatively small input perturbations may occur and even be of practical use (for what I admit, is not obvious). Thus a small impulse artificially given to one body might yield a larger gravitational impulse by a controlled close-encounter with another larger body, and so on. Then a cascade of exponentially growing operations could allow the manipulation of large effects, perhaps in a interestingly short time. A systematic search for orbital 'keyholes' (of the kind familiar from NEA hazard projections, but extended to other pairs of bodies, not just those with Earth) might reveal interesting possibilities for the future. Comet Shoemaker-Levy 9's encounter with Jupiter and (on a larger scale) 2060 Chiron's occasional close encounters with Saturn, come to mind. If a large enough number of such keyholes could be found among smaller bodies, one would expect a characteristic exponential growth time scale, tau,  to emerge, which could perhaps also be estimated theoretically. I wonder if any studies or computational searches have been done along these lines? Wwheaton (talk) 01:42, 12 June 2008 (UTC)

The chaos theory here is handwaving. Toppotu was Belbruno's co-author for a recent ballistic Mars capture paper. From a paper by Toppotu and friends: " Unfortunately, the R3BPs involved in this study, due to their small mass parameters, do not allow the manifolds to develop far enough to approach each other; hence in this case the manifolds do not intersect even in the configuration space." The rocky planets with their tiny mass parameters do not have tubes connecting their Lagrange points. This Interplanetary Transport Network is of little use in the inner solar system. This entire article is exaggerating the benefits.HopDavid (talk) 02:06, 7 November 2015 See http://www.researchgate.net/profile/M_Vasile/publication/40705665_Low_Energy_Interplanetary_Transfers_Exploiting_Invariant_Manifolds_of_the_Restricted_Three-Body_Problem/links/0c960527a98426f09e000000.pdf (UTC)HopDavid

Section removed

I removed an entire section of text here [1] - it mentions things like atomic theory and dynamical systems. I don't think the connection is apparent. Thoughts? --HappyCamper 01:07, 25 August 2006 (UTC)

Some of the papers linked to discuss the relationships, and cover both topics with the same mathematics. I'd personally prefer that the text be left, and the connections made more explicit. Nahaj 01:11, 25 August 2006 (UTC)

Which papers specifically? The dynamics of transition states are quantum mechanical in nature, whereas this is based on classical mechanics. If this connection is really there, it is not stating it clearly. --HappyCamper 01:14, 25 August 2006 (UTC)

Now that you've removed the section, instead of not saying it clearly, it doesn't say it at all. The specific article "Transport in dynamical astronomy and multibody problems" (Part of Caltech's Review and tutorial serices) covers exactly that. And the following three links from the article address the connection directly, just like you would expect from their titles: "Mathematics Unites The Heavens And The Atom" Space Daily, 28 Sep 2005 (in French) "Les mathematiques unifient la dynamique interplanetaire et l'atome" Techno Science (in Spanish) "Las matematicas celestes son equivalentes a las de la fisica atomica" Tendencias 21

I'd rather it not mention the connections at all in the manner that it was like before, but I'll revert the article back to before. It's probably better to leave it there so others can judge for themselves the contents of the papers. An axuillary concern I have now, is that the text that I removed in the edit is rather similar to first paragraph at spacedaily. Some copyright concerns here, but I'll defer that to another Wikipedian to take care of in the future.

I think I'm going to spend time publishing a paper on this instead. Cheers, --HappyCamper 04:58, 25 August 2006 (UTC)

I've rewritten the section in question. Amcfreely 21:53, 5 January 2007 (UTC)

External links - paring down

There are a great number of external links that seem to not be particularly centered on the topic at hand, in particular links to all of the talks by Shane Ross at Caltech. I do not know this topic well, but as a naive reader, it seems that perhaps one or two articles from a given author would be appropriate, but that author's entire on-line publishing and speaking history would be better placed in an article about the person. That said, I've pared down the external links section greatly, but would appreciate discussion here if anyone feels that this is in error. --Zippy 23:15, 8 January 2007 (UTC)

Diagram

It would be useful to show a scientific diagram of how this works, perhaps with a specific example trajectory. -- Beland (talk) 05:24, 21 January 2008 (UTC)

The current image (http:/upwiki/wikipedia/en/thumb/3/33/Interplanetary_Superhighway.jpg/350px-Interplanetary_Superhighway.jpg) looks pretty cool, and is possibly the best attempt at a static representation. To show a realistic sample trajectory would require perhaps an animated gif as the highways are dynamic due to constant orbits of the planets. A 2D figure would be sufficient. Might be something that a little PHP GD programming could do but I'm not sure how to integrate it into Wikipedia. 203.129.23.146 (talk) 07:58, 1 May 2011 (UTC)

Merger Proposal

I am proposing merging Low energy transfers into Interplanetary Transport Network. They have mostly duplicate content. Low energy transfers might fit better as a section inside Interplanetary Transport Network. If anything, Interplanetary Transport Network covers more on the topic of Low Energy Transfers than Low energy transfers does. Allanlw 04:48, 31 December 2008 (UTC)

What's the procedure for moving this proposal on? Seems like the right idea, so... Beeflin (talk) 10:09, 6 October 2010 (UTC)

• Support proposed merge. It should already be showing up in automatically generated list of merge proposals, but you might want to leave a note at WT:AST to get additional attention. --Christopher Thomas (talk) 19:53, 6 January 2011 (UTC)

• Support--If someone wants to integrate Low energy transfers into a section of this article, it would seem to fit. Dave Dial (talk) 18:11, 2 April 2011 (UTC)

• Support Xionbox^₪ 07:08, 4 April 2011 (UTC)

What?

"The key to the Interplanetary Transport Network was investigating the exact nature of these winding paths near the rectal points. They were first investigated by Jimmy Hendrix in the 1890s." Obviously the reference to Jimmy Hendrix is vandalism, so I have removed it, but I have no idea whose name should actually be there. 24.171.21.228 (talk) 16:13, 21 June 2010 (UTC)

If you'd checked the edit history you would have easily found your answer. tildetildetildetilde —Preceding unsigned comment added by 75.164.84.100 (talk) 22:59, 24 June 2010 (UTC)

Other systems?

Would this work for other planetary systems, or is it unique to Earth? This may sound silly, but I would like to know whether this is just because of the arrangement of our system. 81.107.32.163 (talk) 15:12, 12 July 2011 (UTC)

It should apply at least in part to every planetary system; they all have Lagrange points, and any massive body can be used for a gravity slingshot. —Tamfang (talk) 21:47, 16 August 2015 (UTC)

All planetary systems have Lagrange points, yes. But the mass parameters for various 3 body systems vary greatly. The smaller the mass parameter, the less varied the WSBs branching from the L1 and L2 necks. Some 3 body systems with large mass parameters: Pluto-Charon, Earth-Luna, Jupiter-Galilean moon, Sun-gas giant. For the sun and inner system rocky planets, mass parameter is so tiny the WSBs don't overlap. - (pp anon) HopDavid 6 Jan 2016

"WSB" seems to mean "weak stability boundary", but the term does not appear in the article; why not? —Tamfang (talk) 21:18, 10 March 2017 (UTC)

capitalisation

Should the title be capitalised? I suspect not, per MOS:CAPS, because it is not a capital noun. Mitch Ames (talk) 11:59, 3 August 2011 (UTC)

I believe it should be capitalized, because it is indeed a proper noun. Here's a message I left at User talk:ENeville, who un-capitalized the article last September:

I see that you moved Interplanetary Transport Network to Interplanetary transport network last September, citing MOS:CAPS and WP:TITLEFORMAT. I believe that this was wrong: Interplanetary Transport Network is indeed a proper noun: "in its primary application refers to a unique entity, such as London, Jupiter, Sarah, or Microsoft"; it is not "a common noun, which usually refers to a class of entities (cities, planets, persons, corporations), or non-unique instances of a certain class (a city, another planet, these persons, our corporation)". There is only one Interplanetary Transport Network (the Solar System's); its name is not a precise description, but rather an interesting phrase someone came up with to describe the phenomena (see the Big Bang). In addition, the capitalized version is by far the commoner usage: if you look at the WP articles that link to the two capitalizations (ignoring article lists, user pages, talk pages and redirects) there are a total of five links to Interplanetary transport network, but 110 links to Interplanetary Transport Network. Googling turns up similar ratios.

Unless I get strong disagreement I'll be moving it soon. -- Dan Griscom (talk) 20:17, 2 April 2013 (UTC)

I have made the move. -- Dan Griscom (talk) 07:14, 4 April 2013 (UTC)

redirect from InterPlanetary Network

Why is a search for the article title "InterPlanetary Network" redirected here, when there is a distinct article with that title?Michael9422 (talk) 19:45, 20 April 2013 (UTC)

Lede is a little misleading.

I accept, but would not know for sure, that the lede as it stands is a correct and succint summary of the topic. Nevertheless, it does at first glance read like a description of some kind of actual transport system; ie, that it is man-made and indeed possibly in use. And the diagram reinforces the concept. — Preceding unsigned comment added by 58.166.118.138 (talk) 09:55, 19 July 2014 (UTC)

Concur. In truth the entire article reads that way, i.e. that it is or would be "possible" to use these trajectories for meaningful interplanetary travel. The time scales make it unlikely they would be used for this purpose, for either a crewed or robotic mission. How to best add source references that explain that is unclear.... (sdsds - talk) 19:58, 12 June 2015 (UTC)

They have already been used for travel; a probe went out to the solar L1 point and then returned using virtually no propellant. I think a communications satellite also reached geosynchronous orbit using a combination of these techniques and an ion drive.GliderMaven (talk) 20:31, 12 June 2015 (UTC)

I am skeptical WSBs as described by Lo, Marsden and others were used to achieve geosynchronous orbit. Also use of an ion drive is often conflated with use of WSBs.HopDavid (talk) 17:42, 6 January 2016 (UTC)

Yes, but those aren't examples of interplanetary travel, are they? Wouldn't that be how the "Interplanetary Transport Network" would be used? (sdsds - talk) 07:47, 9 September 2015 (UTC)

Well, it is what it is, and you can use it in different ways. Note that it's a transport network, not specifically a transportation network. Many of the things that travel along it would be asteroids and similar that just happen to pass close to a Lagrange point.GliderMaven (talk) 13:12, 9 September 2015 (UTC)

Extent of ITN and mechanism

The stylised depiction shows ITN extending from Venus, Earth, Mars, to Jupiter, Saturn, Uranus etc. Ross-2006 says the tubes from the various L1 and L2 points around different bodies only intersect occasionally. Is this network actually a network of gentle gravitational assists ? If not, where does the energy and momentum come from to get from orbiting earth to orbiting say Jupiter ? Rod57 (talk) 11:03, 26 July 2020 (UTC)

Comments by others (eg HopDavid) above say the weak stability boundaries (WSB's or 'tubes'?) do not extend from Earth to Mars or Jupiter, contradicting the diagram and some text in this article and the Ross-2006 source. Do they (ever) or can't they ? - Rod57 (talk) 11:13, 26 July 2020 (UTC)