11
votes
Object slowest at periapsis - despite correct position calculation
If I understand correctly, your $p, q$ are essentially cartesian coordinates, and you're trying to get the velocity components in those two orthogonal directions.
However, you're taking the derivative ...
- 149k
10
votes
Accepted
In circle orbit, give a delta V to a satellite, how to find final orbit altitude?
To calculate how high your satellite will go, you forgot 1 major thing. The hohmann transfer. I am going to show you how to calculate the transfer from a 600 km circular orbit to another circular ...
- 4,710
9
votes
Accepted
Object slowest at periapsis - despite correct position calculation
As uhoh said, the velocity is the derivative of the position w.r.t. to time, not true anomaly. I.e., if we denote time by $t$, the components of the velocity vector are $\left(\frac{dp}{dt}, \frac{dq}{...
- 2,040
9
votes
In circle orbit, give a delta V to a satellite, how to find final orbit altitude?
A single application of all of the allotted delta V will result in an elliptical orbit with a perigee equal to the original altitude. What you want to do instead is to apply a delta V at the start and ...
- 73.2k
5
votes
In circle orbit, give a delta V to a satellite, how to find final orbit altitude?
In addition to the great answers you have already got, beware of what happens in the extreme case!
The cost of a Hohmann transfer increases by altitude, but only up to a point. After that, the cost ...
5
votes
Transform ECI to ECEF
I know this is a old/dead post but I essentially took on the same challenge and when I googled the answer I kept being brought here. I wanted to add some information here so anyone in the future who ...
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4
votes
In circle orbit, give a delta V to a satellite, how to find final orbit altitude?
Matlab's symbolic toolbox is very helpful to solve this problem. Below, I wrote expressions for $\Delta v$ from initial circular orbit to Hohmann transfer orbit and from Hohmann transfer orbit to ...
- 41
3
votes
sun pointing coordinate system design
For a real mission, there would probably be more pointing constraints than just sun-pointing (likely for communication, thermal, or power reasons). However, for your purposes, you could do this:
...
- 10k
2
votes
In circle orbit, give a delta V to a satellite, how to find final orbit altitude?
I used my Hohmann Spreadsheet inputting 600 km into periapsis for earth orbit and adjusting by trial and error the apoapsis for earth orbit. I look at the sum of the apoapsis and periapsis ...
- 15.6k
2
votes
sun pointing coordinate system design
To orient the ship to face the sun steadily, try the vector of the ship to the sun, and cross that with the velocity vector of the earth relative to the sun (not the ship relative to earth).
...
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1
vote
Using today's technology, is interstellar navigation possible?
Answer: Interstellar navigation is possible using today's technology. Interstellar navigation can use X-rayPulsar-based navigation, technology which has been demonstrated by XPNAV-1 spacecraft and ...
- 17.6k
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