sevenperforce

Yes, but that's beside the point. I'm sticking to "equal inclination but different longitude of ascending node" because that's easier to visualize We definitely don't want that specific special case. Set one of them ahead by the difference in the longitudes of their ascending nodes, then recalculate. You can do this for any two orbits, if you want to rotate one of them to equatorial. Place A at the intersection of the two orbital planes, and place B far enough back in its orbital path that its straight-line distance to the intersection is equal to the straight-line distance that B will be from the intersection when A reaches it. The straight-line distance between the two satellites do NOT lie in either orbital plane. That's the trick. And that, I think, is where the original assumption by @HebaruSan breaks. My guess is that with the right ellipticity, you can have a regular tetrahedron rotating around the planet's axis where each satellite is on the line from the origin to one of the tetrahedral vertices.

Well I don't think it would blow up because the pressure on the outside is still going to be pretty significant. The material integrity of the SRB casing is going to depend on the inside-outside pressure differential, which will probably be less severe than on Earth. Granted, temperatures of roughly 900 F aren't going to do any wonders for aluminum but it still should do okay. I wonder if an SRB, lowered by chute to the surface of Venus (let's ignore that Venus will melt literally every chute material) would be able to develop enough thrust to lift off.

In order to produce thrust, there has to be a flow from inside to outside. If the pressure outside is greater than the pressure inside, then by basic physics there is flow from outside to inside. So the pressure inside the SRB would have to increase above the pressure outside the SRB. Would this happen? Is the pressure environment inside an SRB dependent on the external atmospheric pressure? If the pressure inside an SRB is dependent on external pressure, then does that mean the chamber pressure inside an SRB decreases with altitude as it climbs out of Earth's atmosphere?

Okay, so let me think this through. I'm not quite willing to give it up just yet. The problem, if there is one, must be in "If their inclinations are different, the distances will vary." Yes, it seems intuitively accurate, but is it? Consider two circular Earth orbits A and B, each with an inclination of 45 degrees (just to allow us to use meaningful terminology). Imagine that Earth is frozen underneath and not spinning at all. The longitude of A's ascending node (the point at which the orbital line crosses the equator moving from south to north) is 0 degrees, so the satellite in orbit A will cross the prime meridian and the equator at the same time. The longitude of B's ascending node is 30 degrees east, which means the satellite in orbit B will cross the equator over Kikorongo, Uganda. Suppose both satellites cross the equator at the same time. Depending on orbital altitude, the two satellites will be approximately 3000 miles apart. I don't see any reason why they would ever NOT be 3000 miles apart. They are both following the exact same circle, merely rotated around Earth's axis by 30 degrees, and while their orbital planes certainly intersect, they would not get closer or farther away from each other at any point. At the highest point of its orbit, A will be at 45 degrees north and 90 degrees east, over Qitai County in the Changji Hui Autonomous Prefecture of China. At the exact same time, B will be at 45 degrees north and 120 degrees east, over Jarud Banner in Tongliao, Inner Mongolia. They will still be 3000 miles apart.

I was today years old when I realized that the pressure on the surface of Venus is 50% higher than the pressure inside a Shuttle SRB. Correct me if I'm wrong, but doesn't that mean that if you were to drag an SRB all the way to Venus and then attempt to light it, the pressure inside would not be great enough to escape and so it would not produce thrust?

This sea shanty was by request from the team lead at JPL for the Curiosity team....

I think a mistake was made here. The first satellite is not necessarily unconstrained and cannot necessarily be put in any circular orbit desired. In particular, an equatorial orbit definitely will not work because it necessarily limits the rotational axis of the proposed tetrahedron to the rotational axis of the planet and you can prove trivially that such a configuration doesn’t work, as you did above. A better starting point would be to assume you have two satellites in inclined circular orbits and ask whether there is a set of two orbital planes such that the two satellites remain equidistant. I’m having trouble visualizing it perfectly but I am imagining two 45 degree inclined orbits with different arguments.

On a related note, both the JPL Curiosity Rover team and the Astrobotics Peregrine Lander team have asked me to put together a Space Shanty on TikTok for their respective vehicles. Guess who was just offered free space to deliver actual stuff to the moon??

Yeah I must have misunderstood something in the stream. Weather is generally a problem because dust storms can cover solar panels, but the dynamic pressure from wind is basically negligible due to the low atmospheric density.

They will deploy it tomorrow and do checkouts -- they'll do an initial flight within thirty days.

I stepped in with the Tsiolkovsky rocket equation to answer a question someone asked Tory. The question: The answer: Pretty sure my math is right but let me know if you have corrections.

Me too

I got @torybruno to retweet me!

Ahhhhhhhhhhh Tory Bruno retweeted me!!

WE HAVE TANGO DELTA!!!!!!!!!!!!!!!!!!!!!!

Chute jettison; skycrane ignition!!!!

Chute holding at half the speed of sound, under 5 miles altitude.

Heat shield jettison confirmed!!!

Looks like about 7 gees of acceleration. Past max acceleration, down to well under a gee. Confirmation of chute deployment!!

Confirmation of entry interface and mounting acceleration.

NASA clean feed shows cruise stage separation.

Mars time or Earth time?

"Welcome to EDL."

Someone said that my original PSA wasn't good enough so I set it to music....