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0 pointsdredmorbius11y ago0 comments

Most of your cost-to-orbit is achieving orbital velocity itself. So a marginally lower orbit (LEO is already ~100-250 miles) doesn't seem like it would offer that much in the way of launch cost savings.

Can you substantiate your "much cheaper to launch" statement?

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seanflyon11y ago

The Falcon9 for example has a payload of 13,150 kg to LEO and 4,850 kg to GTO so that is nearly 3 times the cost (http://en.wikipedia.org/wiki/Falcon_9). Every rocket I have checked has a similarly small payload to GTO compared to LEO.

The problem is that even though its not that much fuel to get from LEO to GTO, you have to haul all that fuel up to LEO first.

dredmorbiusOP11y ago

But higher LEO orbits are pretty stable from what I understand. I'd have to look up data, but we're talking centuries to thousands of years for decay, no?

Geosyncronous is a whole 'nother matter, and yes, anything placed there will probably still be orbiting when the Sun goes supergiant. Ponder that.

seanflyon11y ago

After some quick searching I could not find any trustworthy numbers on how long satellites stay up in higher LEO. My impression is that it's decades at most, but I could be way off.

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0 pointsdredmorbius11y ago0 comments

Can you substantiate your "much cheaper to launch" statement?

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seanflyon11y ago

The problem is that even though its not that much fuel to get from LEO to GTO, you have to haul all that fuel up to LEO first.

dredmorbiusOP11y ago

But higher LEO orbits are pretty stable from what I understand. I'd have to look up data, but we're talking centuries to thousands of years for decay, no?

Geosyncronous is a whole 'nother matter, and yes, anything placed there will probably still be orbiting when the Sun goes supergiant. Ponder that.

seanflyon11y ago

After some quick searching I could not find any trustworthy numbers on how long satellites stay up in higher LEO. My impression is that it's decades at most, but I could be way off.

1 more reply

j / k navigate · click thread line to collapse