I'm writing a story about a race that has space travel capabilities without rocket technology, instead is using a portal to space and was wondering whether it's possible for them to put something in orbit, and more precisely:
Is it possible to launch an object into portal A inside a vacuum tube so that when it exits the portal at the point B it would enter earth orbit?
- Side A of a portal is attached to Earths surface and is perpendicular to the surface.
- Side B of a portal opens in space, on a line from the center of the earth, through side A to a point outside of the atmosphere with a (possibly) arbitrary distance. It is aligned perpendicular to the Center-A-B line.
- The velocity vector of a thing entering the portal and exiting the portal is constant.
- The side B of a portal doesn't move. It's fixed in space for the amount of time it takes for the line from earth center through side A to move more than r^2 where r is the radius of the portal. (Clarification: imagine a long pole from the earth to the B side. At portal opening, pole is at -r^2 from the center of the portal and lasts until the pole hits +r^2 from the center of the portal. So if the portal is 2m in radius, the "breakpoints" are at -4m and +4m, so at 1000km the portal would last 0.1097s)
I can't get my head around the math required to compute such an outcome, and was wondering whether you can use Earths gravity to faciliate such a launch.
They use manuevering thrusters and they do have fireworks, but their rocket technology is nowhere near as sophisticated as ours. They rely on ballistics to get the job done.
@JBH: Portal doesn't transfer gravitational forces, only matter and EM radiation (thanks for the heads up on the issue)
And yes, the idea is to make the portal further than the desired orbit and use the "falling to earth" with small manuevering thrusters to "get up to speed". I plan on using the vacuum tunnel to accelerate the rocket on the ground to reduce the fuel requirements even further, because something like even 100m/s is a whole lot of energy I don't need to bring onboard.
As per restrictions, portals are perpendicular to the surface of the sphere at the point of intersection with the ground. Thus no "falling rocketry".
@MarkOlson: The potential energy is technobabbly created from unobtainium radiation. Not something I care about, because there's a lot of ways it could work (energy used to send the matter could include that delta in potential energy) amd have not settled on the way it's done. Thanks for the heads up on this issue.