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I was able to find a feature in STK that allows me to filter such that Access is only achieved and computed when the satellite is in the Umbra or Penumbra (it is called lighting in STK: Constraints - Sun (agi.com)). Following this discovery and implementation, I recomputed access for the following three orbits, all of which met the sun-synched criteria from last week.
Auxiliary things:
- There is also a cool constraint feature in STK that lets you ensure you only compute access for orbits that are above a certain angular rate. As for whether you can see the angular rate, I have not been able to find that property on STK yet.
- There is also a cool constraint allowing you to limit it to times above a certain elevation angle:
- From STK(Introduction to STK (agi.com)): "You know that when you are on the ground trying to see something in space the lower you look along the horizon the more atmosphere you have to look through and the better the chance that something will be in the way. To help avoid the elevation angle problem, STK allows you to put an elevation angle constraint on a ground-based location. A good typical minimum elevation is 6-8 degrees, but it can be more depending on the area, the surrounding terrain, and even buildings."
- There are also a list of other constraints you can impose on Access times (a full list is here:Constraints - Basic (agi.com))
- Notable ones include elevation angle, elevation rate, altitude, and line of sight.
ORBIT 1
a = 15100 km, e = 0.55, inc = 169 deg
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No Antarctica access, per usual. This is the solution we want, but it performs very poorly for some months of the year, sadly. That isn't to say we can't launch two satellites to cover dead zones of the other, though? Plus, since we've seen that times for access haven't gone down for the other satellites when we implement the penumbra/umbra constraint, I'd say it doesn't even matter that we don't put it in the plane of the ecliptic (would you agree)?
So I'm glad that issue was resolved. IF these results look good to you, one final thing I want to do is change the eccentricity for the plane of the ecliptic solution (I arbitrarily set it to 0.3=ecc) to see if there is a lower angular rate solution.