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In fact, I've heard that for polar orbits, you actually have to spent extra energy to cancel out all that speed you got for free - in the wrong axis - from Eart
by emiliobumachar 9y ago
In fact, I've heard that for polar orbits, you actually have to spent extra energy to cancel out all that speed you got for free - in the wrong axis - from Earth's rotation.
- chimere 9y agoThat's right. The most common polar orbits, sun synchronous orbits (SSO), are actually inclined at ~97 deg from the equator. This means that they're moving slightly opposite of the earth's rotation, requiring it to be more than cancelled out. This means that polar launches benefit a bit from launching closer to the poles where the Earth's surface velocity is lower. However, in reality the difficult logistics of building an arctic launch site mean that this is rarely done.
- emiliobumachar 9y ago"rarely done"? Has it ever been done?? Searching for "polar launch" found nothing. (There's actually a Polar Satellite Launch Vehicle [1], but it does not launch from the poles [see Launch History at 1]) [1] https://en.wikipedia.org/wiki/Polar_Satellite_Launch_Vehicle https://en.wikipedia.org/wiki/Polar_Satellite_Launch_Vehicle