Talk:2750: Flatten the Planets

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I have to wonder, would you slide down to the sun, or be flung outwards? SDSpivey (talk) 19:39, 15 March 2023 (UTC)

The discs are centered on the orbit of the parent planet, and presumably rotating at the same frequency as the parent planet's orbit. That means the inner edge of each disc is going slower than you'd need to orbit the Sun at that distance, and the outer edge faster. If you moved inward from the original planet's orbit, the Sun's gravity would pull you in, but when you crossed the boundary to the next disc, you'd get flung back outward.162.158.62.61 19:58, 15 March 2023 (UTC)
No Each planet fills out the space within their orbit into the next planet. Easy to see as the outer edge of Neptune's orbit is the same as with the planet flattened. There is a distance from Mercury to the Sun indicated. Maybe because it would melt if it got any closer? --Kynde (talk) 20:03, 15 March 2023 (UTC)
First, they're rings not discs, but I'm skeptical of the math. And it looks to me like the ring's edges are halfway between the orbits, with Neptune extended outwards the same distance as halfway to Uranus's orbit. 172.69.22.4 20:08, 15 March 2023 (UTC)
My mistake, Randall's math is correct, sorry.
Planet Volume (109 km3) Orbital radius (106 km) halfway to prior halfway to next Annulus area (109 12 OOPS! km2) Thickness (cm 10s of microns)
Mercury 61 58 29 (to 0) 83 19,000 321
Venus 928 108 83 129 30,637 3,029
Earth 1,083 150 129 189 59,942 1,802
Mars 163 228 189 504 685,794 24
Jupiter 1,4310,00 779 504 1,107 3,051,847 46,890
Saturn 827,130 1,434 1,107 2,154 10,726,236 7,711
Uranus 68,340 2,873 2,154 3,684 28,061,145 244
Neptune 62,540 4,495 3,684 5,304 (symmetry) 45,743,348 137
The volumes in this table are at 2 different scales. Only the Mercury to Mars volumes are at 1010 km3. Jupiter to Neptune are at 1012 km3 Sandor (talk) 21:01, 15 March 2023 (UTC)
Thanks, fixed; I had the scale wrong for the radii too. 172.71.158.231 21:16, 15 March 2023 (UTC)
Someone please double-check this, I think Randall is off by a factor of 1000. 172.71.154.229 21:37, 15 March 2023 (UTC)
I did my own spreadsheet, and my figures agree with Randall's (roughly). I think your thinkness figures are mostly out by 1000, and a few of your volume figures also have the wrong scale (Mercury is smaller than Mars, and the giants are too big by a factor of 10). Sandor (talk) 22:07, 15 March 2023 (UTC)
61 * 10^9 km^3 is 6.1 × 10^25 cm^3, 19000 * 10^9 km^2 is 1.9 × 10^23 cm^2, and (6.1 × 10^25 cm^3) / (1.9 × 10^23 cm^2) is 3.2 meters. I'm afraid I'm correct. 172.69.22.145 22:31, 15 March 2023 (UTC)
According to List_of_Solar_System_objects_by_size#Objects_with_radius_over_400_km yes I had Mars wrong (corrected) but the others are roughly correct. I stand by my claim that Randall is in error. 172.71.154.86 22:39, 15 March 2023 (UTC)
Mercury's orbital radius is about 58 * 106 km, not 58 * 109 km, which makes the annulus' area 19000 1012 km2. Sandor (talk) 23:20, 15 March 2023 (UTC)
I fixed that label, hold on... 172.71.154.86 23:30, 15 March 2023 (UTC)
You're right. Thanks. Sorry. Reverted on main. 172.71.154.215 23:39, 15 March 2023 (UTC)

This makes about as much sense as other Flat Earth theories. 172.70.200.137 20:00, 15 March 2023 (UTC)

But this would actually be a flat Earth. Albeit with a rather larger surface area ;-) --Kynde (talk) 20:03, 15 March 2023 (UTC)

But what does the plot of surface gravity vs distance from the Sun look like? Gravity of an infinite plane and all that?--Brossa (talk) 00:01, 16 March 2023 (UTC)

The explanation currently says that it would require "several solar system's worth" of matter, but isn't there enough matter in the actual solar system? --Purah126 (talk) 00:49, 16 March 2023 (UTC)

That was said in reference to the Alderson Disk, which requires 1000km or so of thickness. Clearly more than the proposal here that gives a minute thickness (relatively) from the actual planetary mass in the solar system. Even if you reduced its extent (smaller outer, bigger hole for the Sun) it wouldn't thicken up enough. The prior (non-xkcd) version would require a mass of material rivaling, if not exceeding, that of the Sun itself. 172.70.162.222 02:07, 16 March 2023 (UTC)

One of the reasons NASA rejected this could've been the use of inches. 172.71.102.13 02:26, 16 March 2023 (UTC)

Except for Mars. I can only imagine that use of the metric system for the Mars ring is a reference to the Mars Climate Orbiter fiasco, which certainly would not endear Randall, or his proposal, to a NASA granting agency program officer. 172.70.214.150 02:45, 16 March 2023 (UTC)
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