Latest revision as of 06:19, 3 January 2026

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Conic Sections

Title text: They're not generally used for crewed spacecraft because astronauts HATE going around the corners.

Explanation[edit]

This is incomplete:
This page was created by a section through a scone. Don't remove this notice too soon. If you can fix this issue, edit the page!

A Kepler orbit describes the simplified motion of two celestial objects around each other. Such an orbit will form a conic section. A conic section is a curve obtained from a cone's surface intersecting a plane. The three types of conic section are the hyperbola, the parabola, and the ellipse; the circle is a special case of the ellipse, though it was sometimes considered a fourth type. In reality, this model is based only on their basic gravitational forces and ignores any other factors such as the gravity of other objects, atmospheric drag, each object being a non-spherical(/non-point) body and any relativistic effects, but it serves as the basis for most orbital calculations before further refining with the most relevent additional perturbations.

How conic sections emerge from various planar intersections with bidirectional cones, which technically continue beyond the 'top' and 'bottom' of each diagram.

The conic section as depicted in the comic will be familiar to many readers, since models illustrating these curves using a cone with a base are commonplace and anyone who has learned about these curves in a mathematics class is likely to have seen one.

In real conic sections, the cone extends to infinity. In the comic, however, the "conic section" representing the satellite's orbit has been assumed to have a base at a distance that inconveniently coincides with the presumed otherwise eliptical path, resulting in sharp corners where the angled planar section through the cone meets that base. As alluded to in the title text, these corners would be extremely uncomfortable for an astronaut in a crewed spacecraft. Such an extreme and sudden change in direction would require a very large, potentially dangerous, G-force.

Being in a free orbit necessarily means following an ellipse (or very similar, outside of the mathematically strict two-body problem) without any experienced net acceleration, as adding up the forces due to external gravity and your path's continually changing direction will zero out. Being forced off this ellipse to move across the totally imaginary and arbitrary conic-base would force an instantaneous acute change of direction for no other reason than to follow the imperfectly understood mathematical 'model' at two arbitrary points (reaching the baseline and rejoining the true curve again), which would technically require infinite acceleration each time. Alternately, deliberately 'cutting the corner' would require the best effort of the spacecraft to stick to the truncated-orbital path, requiring as much complex and wasteful thrusting as the craft could provide (which any occupants must endure), including the less uncomfotable but still forceful passage along the 'straight' bit of the orbit through the curved gravitational field of the parent body.

Transcript[edit]

This is one of 35 incomplete transcripts:
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[A view of the Earth, focused on Asia and the Indian Ocean with East Africa at left and the Western Pacific and Australia at right. A satellite is shown in an unusual orbit around the planet.]

[Caption below the panel:]

All Keplerian orbits are conic sections. For example, this one uses the base of the cone.

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This is a test. PoolloverNathan^{[stalk the blue seas]} 20:48, 16 March 2021 (UTC)

A foreign student asked me to help fight against his math teacher. That was unusual. He was in that class for just a couple of weeks. The teacher's phone number was sent to me. The student asked me to spam-call the teacher. 172.71.155.55 22:58, 18 September 2023 (UTC)

here i'm just messing around in html, ignore this

^furhhfghure _{guyrburgryhuyvfr} "rvhru"

interesting way of writing quotations xd

hmmm this one of putting "<p>" in a line break will come in handy for when i want it to start at the same place than the first line

Please beware that <p> on mediawiki also disables automatic paragraph breaks, so you need a closing </p> or you'll break automatic paragraph formatting for the rest of the page. Zmatt (talk) 22:06, 31 July 2024 (UTC)

edit: da hek did that "</div>" come from An user who has no account yet (talk) 14:14, 13 October 2023 (UTC)

hi uh its hard to get here. is this a reference to undocumented feature??? hmm... this is interesting.
108.162.241.216 02:05, 23 November 2023 (UTC)

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yum yum ^{[citation needed]}

Hiuiedeixgeyceiyedhcdiedcve {{trout}}

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3 January 2026

		12:18	Talk:3188: Anyone Else Here‎‎ (4 changes \| history) . . (+664)‎ . . [2600:1001:b009:aed:b591:5d8b:a6f9:a6c3‎; 138.75.75.220‎; 185.36.194.156‎ (2×)]
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Talk:1361: Google Announcement‎ (diff | hist) . . (+202)‎ . . 物灵 (talk | contribs)

		N 05:06	Talk:3189: Conic Sections‎‎ (8 changes \| history) . . (+1,728)‎ . . [Tanner07‎; TheusafBOT‎; SDSpivey‎; PRR‎; 92.23.2.208‎; 71.212.56.254‎; Lordpishky‎ (2×)]
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