=What about other planets than Earth, and other star-systems than Sol’s?
Just so you know Sol is not the official scientific name for the Sun. The Sun doesn't really have any other name. A "sol"ar system is any star that has planets around it. The same for the Moon. It's not Luna, just Moon with a capital "M."
=Where are the best places for interplanetary, and separately for interstellar, spacecraft to “land”, and separately to take off from?
When it comes to landing spacecraft the thicker the atmosphere and weaker the gravity the better. Landing on the moon is relatively simple, even though it has almost no atmosphere, because its gravity is low enough that a suicide burn isn't terribly costly. Mars on the other hand is tricky. It's gravity isn't as strong as earth but neither is its atmosphere. On their own suicide burns would take up too much fuel and parachutes couldn't grab enough atmo to land a spacecraft without crashing it. The common solution is to use both as well as the airbag cocoon, which all together work to soften the landing.
Now when it comes to stellar grabbing - that is falling into orbit around another star - you're gonna want stronger gravity. Presumably if you're traveling from one star to another you're gonna be travelling extraordinarily fast. You're gonna need some serious power and serious time to slow down enough for any star's gravity to catch you. In the future where an interstellar economy has made the resources necessary for this plentiful, you'd presumably have that. But not to digress, the most cost effective area to slow down to "orbit speed" from "escape speed" would be a system with either a large star or several such stars.
=When are the best times to land or take off?
In terms of planetary lift-off and landing a daytime launch is favorable. For landing it obviously helps to see the ground, and for lifting-off any solar panels will be able to start gathering energy immediately. Needless to say favorable weather conditions are a plus. No storms, minimal wind, etc. The temperature is also important depending on the sensitivity of the craft. In the case of shuttle launches, they were only allowed to lift off when the temperature is above 41 degrees Fahrenheit, and below 99 degrees.
In terms of falling into a stellar orbit, the weather on the stars is what you have to watch out for. Are any of them going to flare up? How about coronal mass ejections? The less stable the star the more you're going to have to keep an eye on these events.
=Where are the best places to anchor a space-elevator?
Space elevators have limited practicality. The stronger the gravity of a body, the longer, more sturdy, and more costly the space elevator will have to be. To that end we probably won't be seeing a lot of space elevators on Earth or even Mars sized planets. However building a space elevator on a small moon, planetoid, or asteroid might make a heck of a lot more sense.
Edited February 2nd, 2019
by Louis De Pointe du Lac
Thanks for your answers!
I’ll have to think about them for a day or so (well, really, just a few hours, but even retiree’s have to spend most of the day doing other stuff!) before I can come up with a better, or more germane, response.
Posted February 3rd, 2019
My take is that interstellar ports would be best located on a low circumsolar orbit, then we use light shuttles between the port and the planets of the system. When it comes to passengers only, no heavy freight, I envision the interstellar ship would make no stop but would eject smaller passenger ships to the various solar systems it traverses. But I'm not sure there would be much traffic, as it would probably be immensely cheaper to use local resources to manufacture (or robofacture) anything.
Edited February 28th, 2019
> In terms of falling into a stellar orbit, the weather on the stars is what you have to watch out for. Are any of them going to flare up? How about coronal mass ejections? The less stable the star the more you're going to have to keep an eye on these events.
Is there either a story or a game-idea in this?
Posted April 22nd, 2019
If a spaceport were built near or on Ruwenzori or its African Great Lakes, how would that change their economy and their politics?
Edited May 5th, 2019
In all of these posts, where I typed “geosynchronous”, I probably actually meant “geostationary”.
“Geosynchronous” just means the satellite’s orbital period is the same length of time as the Earth’s rotational period.
“Geostationary” means: geosynchronous AND the satellite appears to hover above a single point on the Earth’s surface.
So its orbit is perfectly or nearly-perfectly circular, and is in the equatorial plane or almost exactly so.
For the central platform of a space-elevator, it really shouldn’t wander very far at all from perfectly directly above its base or anchor-point.
Posted August 9th
NASA chose Florida as the launch site for two reasons:
1 - It's closer to the equator. The Earth's spin gives the rocket the most potential energy, with the greatest pull at the equator.
2 - It's on the East Coast. So a rocket traveling eastward to take advantage of the spin would fly over the ocean, so a disaster would not rain fire over populated cities across the country.
It seems height does not make as big of a difference as the equator when it comes to the best launch conditions for space travel. And safety is a huge concern.
That being said, Cape Canaveral has fairly low population close to the water on Florida's East Coast, which is a compromise given further south you hit Boca Grande and Miami, locations far from ideal.
Posted August 9th
Posted August 10th