Talk:1244: Six Words

2013-07-29T17:11:33Z

Emurphy:

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.

[[Special:Contributions/66.159.155.170|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.
[[User:Wwoods|Wwoods]] ([[User talk: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…

==strictly an orbiter shop==
According to this [http://news.cnet.com/8301-1023_3-57495117-93/mars-curiosity-rover-team-prefers-macs-to-pcs/] that is not true. [[Special:Contributions/212.90.151.90|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?? [[User:Nealmcb|Nealmcb]] ([[User talk:Nealmcb|talk]]) 16:55, 29 July 2013 (UTC)

1244: Six Words

2013-07-29T16:20:03Z

Emurphy: /* Explanation */

{{comic
| number = 1244
| date = July 29, 2013
| title = Six Words
| image = six words.png
| titletext = Ahem. We are STRICTLY an Orbiter shop.
}}

==Explanation==
The {{w|Kuiper Belt}} is a region of the outer Solar System beyond the orbit of Neptune consisting of numerous small icy bodies, including the dwarf planet Pluto. An {{w|Oberth effect|Oberth maneuver}} is a spaceflight maneuver (engine burn) performed during the flyby of a planet or other body; the point of this is to optimize usable energy, because rocket burns are more effective to perform at high speeds than low speeds. The more massive the body and the lower the altitude, the higher the flyby speed will be, and the greater the performance gain due to the Oberth effect. The theoretical way to use rocket fuel most efficiently is therefore to execute the burn during a flyby of the most massive space body available, as close as possible.

Cueball is proposing to implement an "Oberth Kuiper Maneuver" using a Kuiper belt object to provide a gravitational boost to facilitate a flyby of the sun. 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.

Cueball's argument for why the maneuver will work in real life is that it works in {{w|Kerbal Space Program}}, an in-progress sandbox space flight simulator. While it does take into account quite a bit of the physics in a space flight, many liberties were taken in its production, such as a very simple relationship between mass and drag. The humour in referencing it lies in using a simple game program to simulate programs which take a great number of experts to undergo. Use of Kerbal Space Program alone isn't a good enough argument for NASA to agree to implement the proposal; therefore one should not say it at NASA.

The title text refers to {{w|Orbiter_(simulator)|Orbiter}}, which is another space flight simulator program. The title text suggests that the argument doesn't work for NASA, not because it's not scientifically sound, but because the NASA team prefers the Orbiter simulator over the Kerbal simulator (although the proposed maneuver would appear to work in both).

==Transcript==
:The six words you ''never'' say at NASA:
:Cueball: And besides-
:Cueball: It works in Kerbal Space Program.
:[Cueball pointing at a diagram labelled "Proposal:", with the Sun in the middle and a trajectory showing a spacecraft launching from Earth, slingshotting around Venus and a remote Solar System body, then executing a maneuver at close Sun flyby. The label below the diagram reads "Oberth Kuiper Maneuver".]

{{comic discussion}}
[[Category:Physics]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]

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Talk:1244: Six Words

1244: Six Words