Talk:1244: Six Words

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I believe the "Oberth Kuiper Manuver" refers not to the exploitation of the Kuiper belt, but to its the maneuver's usefulness for crossing the belt efficiently. There are multiple various points supporting this conclusion:

1. The size and positioning of the circles strongly indicates that they represent Venus, Earth, and Jupiter (or Eve, Kerbin, and Jool). 2. Reaching the Kuiper belt (which begins at Neptune) requires a great deal of delta-v. Even if you were to slingshot around gas giants (which, in the current explanation, is not shown in the diagram), the trip would consume the majority of a spacecraft's propellant, making the extreme exploitation of the Oberth effect largely ineffective. 3. Kuiper belt objects are very small and therefore would not effectively serve to redirect or slingshot the spacecraft.

66.159.155.170 10:11, 29 July 2013 (UTC)

"This makes no sense, as it it is vastly more expensive in terms of fuel to get to a Kuiper belt object (which is at least 10 billion km from earth) than it is to get to the sun."
This is incorrect. To go directly to the Sun takes a delta-v about equal to Earth's orbital speed (30 km/s). Escape speed is √2 * v_c = 42 km/s; since you start with v_c, you need a delta-v of 12 km/s to get out to the Kuiper Belt. Once you're far from the Sun, a very small delta-v will put you on an orbit passing near (or into) the Sun.Wwoods (talk) 16:47, 29 July 2013 (UTC)
Okay, that's true. But I have another objection to the interpretation: how long would it take to get a probe to the Kuiper belt? And of course there's the problem of actually finding a Kuiper belt object to slingshot around, especially when you've got much better candidates, e.g. Jupiter, Saturn, etc. available for the maneuver. -- Emurphy (talk) (please sign your comments with ~~~~)
The term "Oberth Kuiper Maneuver" does not exist, but Randall did add the word "Kuiper" to the well known "Oberth Maneuver". So he means a Kuiper Belt object. Wwoods' statement is absolutely correct. The trip will just take a long time.--Dgbrt (talk) 18:25, 29 July 2013 (UTC)
I have to agree with the IP address. You're not correct about the Delta_v benefit of going to the Kuiper belt, because Jupiter provides a gravity assist. The probe fires the thrusters at the closest approach to Jupiter in the direction opposite of motion, and this causes it to take a sharper turn, requiring lower Delta_v. This is not possible with the Kuiper belt objects because they are significantly less massive than Jupiter. Yes your speed will be less, but not by enough. The closest approach potential is greater for Jupiter by a factor much greater than the velocity difference. You could do the equations, and I'm sure Jupiter will be more propellant-efficient, in addition to taking less time. AlanSE (talk) 21:40, 29 July 2013 (UTC)
Why the hell you all do TWO spaces after a sentence? Like "IP address.__You're not". But back to the discussion, as more far you are of the massive sun, the the energy for changing the speed direction is reduced, you go back to the sun at HIGH speed.--Dgbrt (talk) 22:57, 29 July 2013 (UTC)
Because that's how you do in on a typewriter. Do you remember typewriters? --Thnidu (talk) 23:07, 29 July 2013 (UTC)
You do not leave Jupiter with zero speed. That's the only way that your argument makes sense. It's not true, so your argument is not true. I am saying that if you sent two of these probes, one doing the incorrect Kuiper object assist, and one just doing a Jupiter assist, the Jupiter-assisted probe would be faster even as the Pluto-assisted was passing Jupiter. That is because the Jupiter-assisted probe does not grid to a screeching halt as it passes the planet like you seem to argue that it does. AlanSE (talk) 15:55, 30 July 2013 (UTC)
Sure, Jupiter would maybe a good option, but Randall mentions the Kuiper Belt. He definitively talks not about Jupiter. The voyage would take more than a decade but the delta-v you need is much smaller than at Jupiter. Randall is just joking about this long lasting mission.--Dgbrt (talk) 19:47, 30 July 2013 (UTC)
strictly an orbiter shop

According to this [1] that is not true. 212.90.151.90 11:59, 29 July 2013 (UTC)

Indeed - thanks! I added that in. Now, is there any evidence that they play Orbiter?? Nealmcb (talk) 16:55, 29 July 2013 (UTC)
edits

I just made a few for sense (undergoimplement), punctuation (possessive it'sits), grammar (and → comma before "eventually leaving"), and logic (inserting if it succeeded,).

--Thnidu (talk) 23:16, 29 July 2013 (UTC)

a.k.a. Dr. Whom: Consulting Linguist, Grammarian, Orthoëpist, and Philological Busybody