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A comment on LightSail 2 Spacecraft Successfully Demonstrates Flight by Light. Parent comment

Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by parsimo2010 on Wednesday July 31, 2019 @09:00PM (#20580292)
I didn’t work on Lightsail, but the article implies that it does aim the sail. It isn’t expanding/contracting, but it does change orientation using the reaction wheels. Basically, they turn the sail broadside to catch the sunlight to raise the orbit, and turn it on edge when they don’t want the extra drag.

This particular satellite won’t ever leave orbit because the sail can’t overcome even the tiny amount of atmospheric drag. If you want to achieve escape velocity with a sail you’ll need a bigger sail and a higher orbit to start out. Right now it’s only feasible for small satellites and we’ve been able to achieve escape velocity using rockets for decades.

Eventually, I do envision a competition to see who can get a payload to Mars with the least amount of fuel. Kind of like the fuel efficiency challenges that college engineering departments participate in today.

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Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by gibolt on Wednesday July 31, 2019 @11:35PM (#20580885)
Hypermiling in space is an awesome concept. Would be so cool to have the solar race competition evolve from cars to spacecraft.
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Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by parsimo2010 on Thursday August 01, 2019 @12:18AM (#20581045)
I have to admit, I got the idea from the beginning of the book Abaddon’s Gate. Solar sails might not be required but I think there’s a future in people plotting slingshot trajectories and sending packages around the solar system as fast and as cheap as possible. One day it will be manned missions, the space equivalent of people that fly hot air balloons around the world.
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Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by initium on Thursday August 01, 2019 @08:57AM (#20583310)
The novels of the James S. A. Corey authors are very inspiring given our recent space achievements. A highly recommended sci-fi series.
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Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by fluffysandwich on Thursday August 01, 2019 @05:46AM (#20582420)
And a couple years after that, Amazon Prime parcels...
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Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by WalterBright on Wednesday July 31, 2019 @11:53PM (#20580956)
> a bigger sail and a higher orbit

But a bigger sail would increase the atmospheric drag!

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Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by parsimo2010 on Thursday August 01, 2019 @12:08AM (#20581012)
But the higher orbit would reduce the drag. You could probably get away with the same size sail, but you’ve got to start high enough that the sail’s tiny thrust over its 50% (ish) duty cycle can overcome the drag present in 100% of the orbit. Once you’re high enough a bigger sail would mean lifting the orbit faster.
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Re:LightSail 2 Spacecraft Successfully Demonstrates Flight b... by peanutz454 on Thursday August 01, 2019 @12:04AM (#20580997)
higher orbit will reduce drag
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