this post was submitted on 03 Sep 2024
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[–] [email protected] 2 points 7 months ago (1 children)
[–] [email protected] 13 points 7 months ago (3 children)

Yo ho yo ho a pirates life for me!

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[–] [email protected] 11 points 7 months ago (1 children)
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[–] [email protected] 13 points 7 months ago* (last edited 7 months ago) (1 children)

I hope it can be sent somewhere neat once they are done testing. But I assume it’s not configured for long range communication.

It would be cool if it could be sent, slowly, to a “nearby” body.

[–] [email protected] 9 points 7 months ago (9 children)

Iirc, solar sail designs like this can actually go stupid fast when properly propelled by something like a laser array.

[–] [email protected] 0 points 7 months ago (3 children)

Just to zoom by the target in 100000 years so quickly no pictures or data can be captured.

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[–] [email protected] 9 points 7 months ago (1 children)

What's fun about these is that the mass of the actual vehicle can be much smaller if it doesn't need to carry rocketry and fuel on board. So even though they'll never compete with rockets for power (energy used over a specific length of time), starting at a lighter weight and never running out of fuel means that these systems could theoretically exceed the top speeds (relative to the earth) of our fastest rockets, given enough time.

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[–] [email protected] 101 points 7 months ago

Thankfully for us, the spacecraft that deployed the sail contains four cameras that can capture a panoramic view of both the reflective sail and the accompanying composite booms. The first of the high-resolution imagery is expected to be accessible on Wednesday, Sept. 4.

I can't wait.

[–] [email protected] 81 points 7 months ago (6 children)

Though photons don't have mass, they can force momentum when they hit an object — that's what a solar sail takes advantage of.

Sounds like a bug.

[–] [email protected] 17 points 7 months ago

Infinite energy glitch

[–] [email protected] 16 points 7 months ago* (last edited 7 months ago) (14 children)

Yeah, why do masless particles have momentum? And please not because law X says so.

[–] [email protected] 37 points 7 months ago (1 children)

In short, even though photons have no mass, they still have momentum proportional to their energy, given by the formula p=E/c. Because photons have no mass, all of the momentum of a photon actually comes from its energy and frequency as described by the Planck-Einstein relation E=hf.

From here: https://profoundphysics.com/if-photons-have-no-mass-how-can-they-have-momentum/

Essentially, momentum is a function of energy, not mass. It's just that massive objects have way more momentum than massless ones.

[–] [email protected] 16 points 7 months ago* (last edited 7 months ago)

Essentially, momentum is a function of energy, not mass.

Thanks! That's the critical piece of information.

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[–] [email protected] 24 points 7 months ago

Must be a problem with floating point precision.

[–] [email protected] 3 points 7 months ago

Witchcraft.

[–] [email protected] 29 points 7 months ago (1 children)
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