Re:SpaceX launches first U.S. national security space mission
by walrus01 on Monday December 24, 2018 @04:06PM
(#18754270)
Vandenberg is mostly used for polar orbit launches because it's a path over the ocean. Not possible to launch eastbound from there because first stages would fall on populated areas. This is also the reason why the Israeli space program launches into rare retrograde orbits (opposite direction of earth's rotation), westbound over the ocean, because they don't want to drop 1st stages on their eastern neighbours.
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Re:SpaceX launches first U.S. national security space mission
by njarboe on Monday December 24, 2018 @04:22PM
(#18754328)
Correct. But the question is, if one wants an inclined orbit, why can't you launch out of Kennedy to the northeast or out of Vandenberg to the southwest. Wouldn't this save all the delta v correction you need to do after getting into an equatorial or polar orbit and then transitioning to an inclined orbit?
Re:SpaceX launches first U.S. national security space mission
by khuey on Monday December 24, 2018 @04:32PM
(#18754383)
You can do both of those. NRO missions have launched out of Kennedy to the northeast (e.g. NROL-76) and Vandenberg to the southwest (e.g. NROL-25).
Re:SpaceX launches first U.S. national security space mission
by njarboe on Monday December 24, 2018 @06:29PM
(#18754872)
According to bisby at the head of this thread, one of the reasons that SpaceX did not recover the booster is that the rocket had to enter an inclined orbit. Maybe it did launch in the direction for an inclined orbit and used a little extra fuel, like a polar orbit does, due to the fact that you don't have all the speed of the spinning earth adding to your orbital velocity. I didn't know that the spinning Earth speed was a significant factor on payload to orbit of rockets.