[X] My Assistant

[Guest_mcmcmc_*]

https://breakthroughinitiatives.org/about

Laser-powered nanocrafts headed to Alpha Centauri:

Breakthrough Starshot is a $100 million research and engineering program aiming to demonstrate proof of concept for a new technology, enabling ultra-light unmanned space flight at 20% of the speed of light; and to lay the foundations for a flyby mission to Alpha Centauri within a generation.

Which are the engineering challenges?
http://breakthroughinitiatives.org/challenges/3

Yuri Milner twitter feed (official?): https://twitter.com/yurimilner

[Gerald]

Frankly speaking, this approach doesn't look like anything feasible to my eyes.
I'd think, that the only technically feasible way to reach 20% of the speed of light would be a linear motor similar to a linear particle accelerator. The probe would need to be really tiny and robust, and take the role of the accelerated particle. Tiny because of the huge amount of energy required, a back-of-an-envelope calculation returned several tera watts for a one gram probe. And robust due to the incredibly high acceleration, at least.
Provided, such a tiny probe can be accelerated to the presumed velocity, and it won't be destroyed by interplanetary or interstellar matter, how will it be able to send back data over a distance of several light years? The incredibly robust tiny bullet would need to unfold into a huge antenna of presumably an average layer thickness of less than an atom, with a well-defined parabolic shape, and pointed accurately to Earth.
I think, it's less than 1% science and more than 99% fiction in a world with finite ressources.

[marsbug]

Frankly speaking, this approach doesn't look like anything feasible to my eyes.
I'd think, that the only technically feasible way to reach 20% of the speed of light would be a linear motor similar to a linear particle accelerator. The probe would need to be really tiny and robust, and take the role of the accelerated particle. Tiny because of the huge amount of energy required, a back-of-an-envelope calculation returned several tera watts for a one gram probe. And robust due to the incredibly high acceleration, at least.
Provided, such a tiny probe can be accelerated to the presumed velocity, and it won't be destroyed by interplanetary or interstellar matter, how will it be able to send back data over a distance of several light years? The incredibly robust tiny bullet would need to unfold into a huge antenna of presumably an average layer thickness of less than an atom, with a well-defined parabolic shape, and pointed accurately to Earth.
I think, it's less than 1% science and more than 99% fiction in a world with finite ressources.

My understanding is that the physics is sound and well understood, except perhaps on the matter of the antenna, which I've not done much reading on. The engineering requirements, however, are.... no cause for optimism.I've heard plausible rebuttles to most objections to the physics, again except on the transmission of data to Earth. But, again, the engineering objections are significant. Still, that's the point of the initiative: To research the issues and determine how far away we are - at least to my understanding. I've not heard anyone seriously suggesting we'll get a star-probe from this. It's laying the foundations of the foundations.