51–60 of 76 posts
This is probably a tremendously dumb question, but what are the major impediments to literally sticking a big freaking balloon to the top of a rocket and floating it up much of the way?
Why bother with the rocket? It sounds mad, but you can actually just send the balloon. to orbit... http://www.jpaerospace.com/atohandout.pdf
Earlier quoted context omitted.
The altitude gain is significantly less important than the horizontal velocity. An aircraft can easily launch from the equator and add 650+MPH.
Note that this launch wasn't from the equator, because this constellation needs to overfly hurricanes. It's fairly uncommon for LEO satellites to want to be at the equator. GEO, extremely common.
This is probably a tremendously dumb question, but what are the major impediments to literally sticking a big freaking balloon to the top of a rocket and floating it up much of the way?
Why bother with the rocket? It sounds mad, but you can actually just send the balloon. to orbit... http://www.jpaerospace.com/atohandout.pdf
Earlier quoted context omitted.
For those of us just watching, what is attitude? At first I though spellcheck might have corrected it from altitude, but 3 times among 2 differently people I see attitude.
It's orientation, AFAIK, what direction it's facing.
Earlier quoted context omitted.
I have this dream that someday we'll build a SR-710 that's 10x the size and carry a BIG payload. And then putting stuff into orbit will basically be strapping your thing to a "big" upper stage (but small relative to a whole rocket stack), loading it into the cargo bay and then some fancy flying. I know it'll never happen for a variety of reasons. But it's such a cool plane and when you think about cruising at mach 3…
One big reason it'll never happen: The square-cube law. https://en.wikipedia.org/wiki/Square-cube_law
Earlier quoted context omitted.
Star trackers are usually just used for attitude, not position. I've heard of research to use them in conjunction with a camera pointed at Earth to resolve coastlines to get position, but it's very theoretical at this point AFAIK.
For those of us just watching, what is attitude? At first I though spellcheck might have corrected it from altitude, but 3 times among 2 differently people I see attitude.
Attitude is which direction your face is pointing. Imagine a satellite meant to photograph the earth at the right altitude but the wrong attitude could just be taking nice shots of outer space.
Earlier quoted context omitted.
Note that this launch wasn't from the equator, because this constellation needs to overfly hurricanes. It's fairly uncommon for LEO satellites to want to be at the equator. GEO, extremely common.
Launching from the equator is useful for a wide range of orbits as a component of the final vector 1600km/h is really not that fast and your final orbit crosses the equator anyway. The only issue is if the ideal launch point is not over the ocean. Also, there is a wide band near the equator with close to optimal velocity.
Earlier quoted context omitted.
Note that this launch wasn't from the equator, because this constellation needs to overfly hurricanes. It's fairly uncommon for LEO satellites to want to be at the equator. GEO, extremely common.
Launching from the equator is useful for a wide range of orbits as a component of the final vector 1600km/h is really not that fast and your final orbit crosses the equator anyway. The only issue is if the ideal launch point is not over the ocean. Also, there is a wide band near the equator with close to optimal velocity.
For example Saturn V used 40% of its total fuel to get up to this speed. That's a huge savings.
Unless I am reading the data incorrectly:
Granted, it's a little tricky to transport rockets, but surely it would have made more sense to move the operations to a mountain near the equator?
How much fuel would be saved by lunching 3000 meters above sea level instead?
A little off topic.. I've always wondered why NASA lunched rockets from Cape Canaveral (only 3 meters above sea level). Granted, it's a little tricky to transport rockets, but surely it would have made more sense to move the operations to a mountain near the equator? How much fuel would be saved by lunching 3000 meters above sea level instead?
Altitude is not even the most difficult part of getting to orbit. Getting to the necessary horizontal speed to stay in space takes a hell of a lot more fuel than going straight up.