Talk:Breakthrough Starshot

Alas, the article is not good.
Sorry, but it being a phased array is critical to the idea. You need to get the spot size small enough that you can keep it on a small sail on a long journey.

Furthermore, the intro leads what it claims to be able to do, making it sound like fantastical claims, to be frank.88.159.64.181 (talk) 17:29, 19 July 2017 (UTC)


 * @88.159.64.181 The article explicitly states "A phased array of ground-based lasers would then focus a light beam on the crafts' sails to accelerate them one by one to the target speed within 10 minutes", so your objection is unfounded. This is not to say that there may not be other insurmountable problems with the concept. Abuldiz (talk) 17:30, 6 February 2023 (UTC)

Size of phased array
I'll add a cn needed tag to the intro, as I'm not sure where the figures in the lead para. come from. This source  says "100-GW phased laser array 10 km on a side" Robert Walker (talk) 17:43, 3 August 2017 (UTC)


 * I've discovered, the earlier 2015 study is for a 1 km square array, sounds just like the lede of the article, so perhaps that's where the figure comes from? 15 minutes into this video Robert Walker (talk) 04:21, 4 August 2017 (UTC)

Optical or radio communication?
The text (now hiden for being contradictory) states: "Each spacecraft would transmit data back to Earth using a compact on-board laser communications system using its solar sail as an antenna and the propulsion array as the receiver.

First, if the communication will be laser, that means an optical system, so it cannot possibly use an "antenna" for that. Second, the propulsion array on the ground are lasers, but in order to receive an optical signal, the system needs an optical telescope. Please review the optical laser concept at Deep Space Optical Communications and Laser communication in space. So this entry needs review for the system to be used - optical or radio signals. Cheers, BatteryIncluded (talk) 20:03, 25 December 2017 (UTC)


 * Per the Breakthrough Starshot project homepage:
 * Per the Breakthrough Starshot project homepage:


 * {| class="wikitable"


 * ''' The program will require:
 * Capturing images of a planet, and other scientific data, and transmitting them back to Earth using a compact on-board laser communications system.
 * Using the same light beamer to receive data from nanocrafts over 4 years later.


 * }
 * }


 * P.S. Your citations are empty.
 * — Altman  talk  22:21, 25 December 2017 (UTC)


 * Those citations had been copied from the article. Looks like they should have been and . 156.68.221.92 (talk) 13:13, 27 September 2021 (UTC)

flyby or enter orbit
Article says flyby a few times. Only mention of entering orbit is in Other potential destinations section. perhaps this section should be moved to light sail as it seems not specific to Breakthrough Starshot ? - Rod57 (talk) 18:16, 18 October 2020 (UTC)


 * Starshot is a fly-by probe. The "Other Potential Destinations" section referred to a 2017 paper by René Heller and co-authors, proposing that it may be possible to stop using a technique that they call "photogravitational assist". I'm not sure whether this result is widely accepted in the scientific community, but it was published in a reputable journal. I changed the subheading title and revised the text to try to make this more clear. 156.68.221.92 (talk) 13:22, 27 September 2021 (UTC)

Name convention
Prof. Nobuyuki Kaya's name was listed as Kaya Nobuyuki (in the Japanese name convention, family name first). Other articles on Wikipedia usually gives Japanese names in the English language order (given name then family name), so I changed this to the more standard Nobuyuki Kaya. If we want to keep the Japanese name order, go ahead and change it back. 156.68.221.92 (talk) 13:13, 27 September 2021 (UTC)

"Photon thrusters"??
"Four sub-gram scale photon thrusters, each minimally capable of performing at a 1W diode laser level, are planned." This is not mentioned in the referenced sources afaics - and isn't this a mix-up with the communication laser (to send back the images)? Four 1 Watt lasers don't produce any significant propulsion. --Felix Tritschler (talk) 21:01, 28 December 2021 (UTC)

Fusion
Given the announcement yesterday and the discussions on funding and commercial designs today between the DOE and basically every fusion startup demonstrating that when Sec. Granholm said 10 years to commercialization, it appears she meant it. With that said, your initiatives for a starshot program should now explore fusion solutions. It’s go time. 2601:2C7:67F:5510:C541:5AD:BB3C:BFE8 (talk) 07:37, 15 December 2022 (UTC)

Spurious precision
5sf for the flight times for the orbital insertion approach is far too great. It should be years at most. Vicarage (talk) 16:49, 17 December 2023 (UTC)

Concept
The usage of space based laser system is much more usefull and cost effective, since it can be used multiple times for many probes at the same one time launch cost. The laser array can be solar powered, and take a longer time to achieve the speed desired. Note that a space based laser system can target more effectively, since it doesn't involve taking into account light breaking by atmosphere and such, but also has less loss due to not having to pass through the atmosphere dispersing on top of the breaking. This all would lower the need for output to maybe 1GW. I'd still add at least one 360degree lightweight ion thruster, since besides the speed required course correction need to be made as the vessel gets near Proxima, which can't be achieved by long distance laser targetting. (trust me, I'd know if that were possible, but even using single atoms for arc correction, isn't fine enough to do laser correction at such distances.) It would be a waste to almost get the job done, since the wait is very long. What even the best telescopes can't do is correcting light source deviation from observed, which always happens in space at LY distances. Where you observe the target to be is not where it is, and trust me on this too, extrapolation in this matter is extremely hard for the finesse of outcomes required to actually pass the planet close enough to be of any use. It's not like Mars where you can send a command and only minutes later it gets followed up on. Any remote commands to a target 2+ LY away will take 2+ years to be followed up on. At some point the probe would have to think for itself and adjust it's course on it's own power and according to it's programming. I also think the best first step is to launch any probe towards Proxima B, not for the mission itself, but to verify the circumstances through which the factual probe will have to travel. Save a camera and a 360 degree ion thruster, solar sails, and a tracking locator nothing else, with the sole purpose of reaching the outer Oort clouds, travelling past it, and then checking the circumstances there, possibly near miss course towards Proxima b. This can even be a regular ion thrust driven probe, which doesn't require the full 1 GW space laser required for the factual mission. Since the factual mission is one for like 3-4 decades from now, the test probe can make the journey to the Outer Oort cloud and send back detailed info on the circumstances between here and there, while also giving more accurate data on Proxima b's real position, undisturbed by any gravitational influences or such which things like JWST can't. It will also be a test for getting beyond the Outer Oort cloud in one piece, since meteoric debris and micro dust can do a lot of damage travelling on collision with any craft moving at 0.1 c. If the probe can't get that far, it's impossible for any faster probe to travel there since it would sustain even more damage but also with the light weight the dust can deviate it from it's course, completely missing Proxima b's extrapolated position.

Note: I wouldn't hope for a 20-30 year travel time, that's maybe maybe maybe. I'd say 45-90 years.

Note2: The craft itsself would be breaking as it nears Proxima b, since the solar sails will receive light pressure from it's parent star. This will also deviate the planned course, which the probe will have to correct for with it's own software and power.