Linked Questions

2answers
113 views

Are there any satellites in geosynchronous orbits that are neither geostationary nor 'wobbly geostastionary' (figure of eight geostationary)?

None of the examples in this question: Are there any satellites in geosynchronous but not geostationary orbits? are nothing like geostationary. They still stay above the one side of the earth. What ...
1answer
124 views

Does Tianwen-1 have a near-repeat ground track orbit in order to scan the same general area on each of its low altitude passes?

Though it's not as easy1 to get details on Chinese missions in English, it seems that Tianwen-1 is in a 12,000 x 256 km highly eccentric orbit around Mars, with its hi res cameras able to resolve 0.5 ...
1answer
273 views

Under what conditions can a non-resonant satellite stay hidden from an observer on the ground?

From the perspective of someone on the ground, a satellite is usually not above the horizon all the time. But can a satellite have such an orbit that it is never above the horizon? Such orbits clearly ...
2answers
637 views

Rocket to launch 8 cubesat to LEO at an equidistant distance

I am working on a project, which consists of the launch of 8 cubesat 1U to LEO (Low Earth Orbit) and I started working on the launch part, the idea of ​​the project is to be as cheap as possible, the ...
1answer
638 views

Does the "17" really mean anything with respect to GNSS orbits being rational factions of a sidereal day?

This answer to Why are orbital periods different for different GNSS positioning system constellations? suggests that the orbital periods of the four large GNSSS constellations are linked to the ...
1answer
3k views

How do I determine the ground-track period of a LEO satellite?

I was analyzing a LEO satellite with polar orbit for work purposes. I am relatively new to the field of Satellite orbits. I know that TLE can give information about the current & future orbits ...
2answers
224 views

Is Dawn's upcoming low periapsis orbit for XMO7 "resonant"?

The Spaceflight Insider article Dawn will enter lowest ever orbit around Ceres says: In his Dawn Journal blog, mission director and chief engineer Marc Rayman discussed the challenges of bringing the ...
1answer
322 views

How long would a satellite fly on a sun-synchronous 600km orbit?

How long would it take for a 12U cubesat on a circular polar orbit with altitude 600 km to fall down to 500 km? Please, add references/calculations to your answer.
2answers
3k views

Difference between Tundra and Molniya orbits?

This excellent answer nicely describes both Tundra orbits and Molniya orbits. They are both repeat groundtrack orbits with periods of rational fractions of a sidereal day, and both have inclinations ...
1answer
353 views

Trying to understand the two "holes" in this alt/az plot of the ISS

I'm plotting the position of satellites in the sky using Skyfield. If I project the .altaz() data on to a rectangle (in a similar fashion to the way ground track ...
1answer
538 views

How long does it take for ISS to travel over all possible places of the world one time?

ISS has an inclination of about 56 degrees but because his orbit is not exactly a whole part of 24 hours, ISS will the next day be above other places. So after a while he has 'visited' most of the ...
1answer
3k views

The strange orbit of Ofeq 11 - how does it (actually) do this?

I assume the retrograde orbit ($\theta_{inc}=142°$) is a side-effect of geography - ocean overfly access only lies West of the secured launch site - this article in Spaceflight 101 makes several ...
1answer
1k views

What (actually) is a 1:1 resonance, and is 2016 HO3 in one with the Earth?

In my question How was Earth's "quasi-satellite" 2016 HO3 "first spotted" and it's orbit determined? I link to two videos of simulations of views of 2016 HO3's orbit seen in two ...
2answers
2k views

Are sun synchronous orbits possible for any place on Earth?

Do sun-synchronous orbit pass any spot around Earth at a specified local time? If yes or no, what is the reason? (I know that this type of orbit passes everywhere at the equator at the same local time....