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Exactly, there was a great animation posted here once that showed the hobs with and without lasers. Given that there are examples of 44+ terabits[1] being trans

Exactly, there was a great animation posted here once that showed the hobs with and without lasers. Given that there are examples of 44+ terabits[1] being transmitted optically I am not too worried about the bandwidth. I'd love to be on the Starlink team, they are building some really cutting edge stuff. There are not many places or times where you can have such a big impact on the world and their team happens to be one of them. Good times. [1] https://www.sciencedaily.com/releases/2020/05/200522095504.htm https://www.sciencedaily.com/releases/2020/05/200522095504.h...

snoshy 6y ago
This seems overly ambitious, and not likely to translate to laser satellite comms links. Remember these sats are in low LEO, so there is at least some amount of non-uniform atmospheric medium to create optical distortion that you wouldn't have in a tightly controlled environment from your link (chip, datacenter, what have you). Then there's the issue of signal attenuation at distances like these, along with the power budget from the solar panels to ensure that you aren't burning all your power just on laser comms. I can't imagine these links would be anything more than 1:1 at any given time, at least not at first. Maybe later they might be able to handle simultaneous laser links from 1:3 or something like it, but I highly doubt that's their current capability. Even some of the best latest ground-to-sat laser comms links are on the order of ~7 gigabits per second. [1] I imagine those are far larger sats than Starlink, and their entire power and thermal budget is likely spent on comms. And the ground stations can be orders of magnitude larger and power hungry in relation to a Starlink sat. Note also that this is from GEO, so you aren't likely having to handle substantial relative movement either. [1] https://en.wikipedia.org/wiki/Laser_communication_in_space#2011-present https://en.wikipedia.org/wiki/Laser_communication_in_space#2...
- BenjiWiebe 6y ago
  Seems like a LEO-to-LEO laser link would be shorter, lower noise, and lower power for the same bandwidth as a GEO-Earth link.
- lutorm 6y ago
  Space to ground is a lot harder than space to space. There is no atmosphere to deal with and in most cases the relative velocity is lower.
- mapt 6y ago
  The link between neighboring satellites in a 22-satellite-per-plane constellation at 550km altitude comes at its closest 480km above the ground. The link between next-farthest-neighbors comes at its closest 270km from the ground. The link to the second-farthest-neighbor is not in line of sight. Optical effects at 270km or 480km altitude are negligible; 99% of the atmosphere's mass is below 30km altitude. In theory you could go all the way down to an 8-satellite plane at 550km and still maintain line of sight and freedom from most of the atmosphere's interference. Satellite-to-ground optical laser links are another matter, but you can always route a few hops around weather systems.
jacquesm 6y ago
So, why not apply? You certainly have the required skillset and with your experience level I'd assume they would jump at the opportunity.
- lutorm 6y ago
  Indeed, why not! We have an absurd number of software job openings now, both on the Starlink network side and the flight software / simulation side. Bonus points if you have a top secret clearance. https://www.spacex.com/careers https://www.spacex.com/careers, category "software development".
  - mercutio2 6y ago
    I imagine ChuckMcM's reasons may be similar to my own: when last I checked, SpaceX didn't have any positions open for Bay Area residents unwilling to relocate. But I do see on the careers page there's now a (single) Palo Alto based Software Engineer position open. Intriguing!
  - rchard2scout 6y ago
    There's some jobs in there that are absolutely my dream job. But unfortunately, I probably can't due to ITAR requirements, I'm not from the U.S. Or does the "eligible to obtain the required authorizations from the U.S. Department of State" apply?
    - lutorm 6y ago
      It is possible to get ITAR authorization without being a US citizen or permanent resident. However, it is a long and arduous process, and even then those employees are restricted from some information. For that reason, it probably won't be considered unless you are very highly qualified. If I were you, I'd read up on ITAR qualification and, if you think you would be eligible and are highly qualified, just apply.
  - ChuckMcM 6y ago
    Well there are a couple of reasons one might not, but the biggest one is that given people with a wide range of experience in both individual contributor and management roles it is often difficult to figure out how to match the skillset with the role. Send me an email (profile has it) and I'll send you a resume you can dump into the ATS system to see if anyone thinks I'd be a good fit. (And no, I don't send my resume to head hunters to shop around). The second challenge is that I am in a position to be reasonably frank when the biggest threat one can hold over me is to be fired. I have found that some managers don't appreciate employees for whom their "hire/fire power" over them doesn't give them any leverage. This combined with a general perception that I am a good manager, means that I tend to develop a followship whether or not I'm in a leadership role. This can lead to "issues" no matter how hard I try to prevent them.
mhandley 6y ago
Do you mean this animation? https://youtu.be/m05abdGSOxY https://youtu.be/m05abdGSOxY
- ChuckMcM 6y ago
  Yes! Thanks for finding it again. I now have it bookmarked!
  - Seanambers 6y ago
    He's the one who made the animations. They're incredible :)
    - jacquesm 6y ago
      Indeed, what a fantastic skill both in animation but also in communicating a complex concept. I missed this the first time around, so much appreciated.

snoshy 6y ago

This seems overly ambitious, and not likely to translate to laser satellite comms links. Remember these sats are in low LEO, so there is at least some amount of non-uniform atmospheric medium to create optical distortion that you wouldn't have in a tightly controlled environment from your link (chip, datacenter, what have you). Then there's the issue of signal attenuation at distances like these, along with the power budget from the solar panels to ensure that you aren't burning all your power just on laser comms. I can't imagine these links would be anything more than 1:1 at any given time, at least not at first. Maybe later they might be able to handle simultaneous laser links from 1:3 or something like it, but I highly doubt that's their current capability. Even some of the best latest ground-to-sat laser comms links are on the order of ~7 gigabits per second. [1] I imagine those are far larger sats than Starlink, and their entire power and thermal budget is likely spent on comms. And the ground stations can be orders of magnitude larger and power hungry in relation to a Starlink sat. Note also that this is from GEO, so you aren't likely having to handle substantial relative movement either. [1] https://en.wikipedia.org/wiki/Laser_communication_in_space#2011-present https://en.wikipedia.org/wiki/Laser_communication_in_space#2...

BenjiWiebe 6y ago
Seems like a LEO-to-LEO laser link would be shorter, lower noise, and lower power for the same bandwidth as a GEO-Earth link.
lutorm 6y ago
Space to ground is a lot harder than space to space. There is no atmosphere to deal with and in most cases the relative velocity is lower.
mapt 6y ago
The link between neighboring satellites in a 22-satellite-per-plane constellation at 550km altitude comes at its closest 480km above the ground. The link between next-farthest-neighbors comes at its closest 270km from the ground. The link to the second-farthest-neighbor is not in line of sight. Optical effects at 270km or 480km altitude are negligible; 99% of the atmosphere's mass is below 30km altitude. In theory you could go all the way down to an 8-satellite plane at 550km and still maintain line of sight and freedom from most of the atmosphere's interference. Satellite-to-ground optical laser links are another matter, but you can always route a few hops around weather systems.

jacquesm 6y ago

So, why not apply? You certainly have the required skillset and with your experience level I'd assume they would jump at the opportunity.

lutorm 6y ago
Indeed, why not! We have an absurd number of software job openings now, both on the Starlink network side and the flight software / simulation side. Bonus points if you have a top secret clearance. https://www.spacex.com/careers https://www.spacex.com/careers, category "software development".
- mercutio2 6y ago
  I imagine ChuckMcM's reasons may be similar to my own: when last I checked, SpaceX didn't have any positions open for Bay Area residents unwilling to relocate. But I do see on the careers page there's now a (single) Palo Alto based Software Engineer position open. Intriguing!
- rchard2scout 6y ago
  There's some jobs in there that are absolutely my dream job. But unfortunately, I probably can't due to ITAR requirements, I'm not from the U.S. Or does the "eligible to obtain the required authorizations from the U.S. Department of State" apply?
  - lutorm 6y ago
    It is possible to get ITAR authorization without being a US citizen or permanent resident. However, it is a long and arduous process, and even then those employees are restricted from some information. For that reason, it probably won't be considered unless you are very highly qualified. If I were you, I'd read up on ITAR qualification and, if you think you would be eligible and are highly qualified, just apply.
- ChuckMcM 6y ago
  Well there are a couple of reasons one might not, but the biggest one is that given people with a wide range of experience in both individual contributor and management roles it is often difficult to figure out how to match the skillset with the role. Send me an email (profile has it) and I'll send you a resume you can dump into the ATS system to see if anyone thinks I'd be a good fit. (And no, I don't send my resume to head hunters to shop around). The second challenge is that I am in a position to be reasonably frank when the biggest threat one can hold over me is to be fired. I have found that some managers don't appreciate employees for whom their "hire/fire power" over them doesn't give them any leverage. This combined with a general perception that I am a good manager, means that I tend to develop a followship whether or not I'm in a leadership role. This can lead to "issues" no matter how hard I try to prevent them.

mhandley 6y ago

Do you mean this animation? https://youtu.be/m05abdGSOxY https://youtu.be/m05abdGSOxY

ChuckMcM 6y ago
Yes! Thanks for finding it again. I now have it bookmarked!
- Seanambers 6y ago
  He's the one who made the animations. They're incredible :)
  - jacquesm 6y ago
    Indeed, what a fantastic skill both in animation but also in communicating a complex concept. I missed this the first time around, so much appreciated.