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Editing 1244: Six Words
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==Explanation== | ==Explanation== | ||
− | The | + | 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 planets {{w|Pluto}} and {{w|Eris (dwarf planet)|Eris}}. An {{w|Oberth effect|Oberth maneuver}} is a spaceflight maneuver, assisted by an engine burn, performed during the flyby near an other celestial body. The point of this is to optimize usable energy, because rocket burns are more effective to perform at high speeds than at 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", and the proposal diagram shows the spacecraft using {{w|Gravity assist|gravity assists}} to slingshot towards a distant body after first travelling toward {{w|Venus}} for a first boost, and then heading back towards the Sun by using the the "Oberth Maneuver" at an Kuiper Belt object. The travel to an object so far will take a long time, but the advantage would be that the probe does not need to alter its speed that much to reach the sun as it would be necessary at a solar distance at earth's orbit. After that maneuver the probe will just ''fall'' into the direction of the sun. | |
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− | + | Such a maneuver, while theoretically possible, would however be infeasible in real life, because the spacecraft could be incinerated during a too-close flyby of the Sun. But if it succeeded, the probe would accelerate to high speed, eventually leaving our solar system. | |
− | + | 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 implement. 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 NASA relies on the Orbiter simulator rather than the Kerbal simulator (although the proposed maneuver would appear to work in both). Note, however, that [http://news.cnet.com/8301-1023_3-57495117-93/mars-curiosity-rover-team-prefers-macs-to-pcs/ a few team members "love" to play Kerbal]. (OK, it is getting bad when explainxkcd needs it's own explain; the "Kerbal vs Orbiter" is a simple reference to the nerdy PC vs Mac argument). | |
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− | + | The identity of the distant object is unclear, but it could be Pluto or Eris. Nevertheless, there are many more (even unknown) objects at the belt. | |
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==Transcript== | ==Transcript== | ||
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:The six words you ''never'' say at NASA: | :The six words you ''never'' say at NASA: | ||
− | + | :Cueball: And besides- | |
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− | :Cueball: And | ||
:Cueball: It works in Kerbal Space Program. | :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".] | ||
==Trivia== | ==Trivia== | ||
− | * | + | *{{w|NASA}} is planning a mission to the sun at a closest distance of only 8.5 solar radii. The {{w|Solar Probe Plus}} will use seven Venus flybys to reach its [http://solarprobe.jhuapl.edu/index.php first close approach]. The maneuvers will last nearly seven years, before the real mission does start. |
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{{comic discussion}} | {{comic discussion}} | ||
− | + | [[Category:Physics]] | |
[[Category:Comics featuring Cueball]] | [[Category:Comics featuring Cueball]] | ||
[[Category:Comics featuring Ponytail]] | [[Category:Comics featuring Ponytail]] | ||
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