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There are two different explanations that I've read over the last few months for why we didn't see laser links on previous rounds of Starlink satelites. First,

by zaroth 6y ago

There are two different explanations that I've read over the last few months for why we didn't see laser links on previous rounds of Starlink satelites. First, that the unit pricing was too high. SpaceX is targeting an extremely (absurdly) low price of $250,000 BOM per satelite, and it was theorized that the laser links were blowing the budget. Estimated that it would cost ~$100k for the lasers, targeting, and electrical systems to add the links. Second, I've read that they had issues guaranteeing that all the components of the laser system would fully burn up in the atmosphere. One of the conditions of launching low-orbit satellites is that they will fully burn up on re-entry (therefore not posing any risk when they fall back down to earth). Apparently some of the optics components had a chance of survival and ultimately possible land-impact. I'm not sure if we can say that this launch indicates that the cost issue has been solved. It could be worth blowing out the BOM to get some operational experience having a few birds with the lasers, so perhaps they haven't fully solved the pricing issue unless we start seeing lasers on every subsequent launch. TFA has a great animation of a polar orbit. It's basically a longitudinal orbit, so it will absolutely pass over land for a lot of the time, so clearly they must have at least solved the burn-up issue, if in fact that actually was ever an issue in the first place. Also, FYI, there was a scheduled attempt to launch SN9 today, but it just got scrubbed a minute ago due to winds. They will be trying again tomorrow! reddit.com/r/spacex is a good place to watch for updates: https://www.reddit.com/r/spacex/comments/krllbt/starship_sn9_test_no_1_high_altitude_launch/ https://www.reddit.com/r/spacex/comments/krllbt/starship_sn9...

neaanopri 6y ago
It's probably the BOM cost. I've seen the "burn up in the atmosphere" constraint before, and it struck me as a bit crazy for Shoot First and Ask Questions Later SpaceX to care about this
- jccooper 6y ago
  Demisability is a significant regulatory concern... but I suspect it wasn't flying before mostly because they didn't have it working yet.
- jandrese 6y ago
  That requirement could have come from the government. It's not a crazy thing to ask for when you're launching literally hundreds of satellites into LEO. Plus, the last thing SpaceX wants is a news story about killer satellites raining debris on innocent citizens. Remember that each satellite launched has to be deorbited eventually, so if they're launching dozens of sats per month they'll eventually be deorbiting dozens of sats per month. If they don't fully burn up each one will have a chance of hitting someone. Sure the chance may be very small, but when you're rolling the dice dozens or hundreds of times per month eventually you're going to land on snake eyes.
- temp667 6y ago
  They are explicitly pursuing a demisable sat design. Note - despite other posters claims, this is not a requirement and there are other approaches as well for the safety side here. The most common is to deorbit into the ocean (the sats are maneuverable) with a failure rate and part hazard rate low enough that remaining risk is minimized. I would expect they would deorbit into ocean / near non-populated areas for other reasons as well.
- Tuna-Fish 6y ago
  > I've seen the "burn up in the atmosphere" constraint before, and it struck me as a bit crazy for Shoot First and Ask Questions Later SpaceX to care about this SpaceX has never been even a little careless about following laws, regulations and staying within the lines of their FCC/FAA authorizations. There is this reputation surrounding them, probably because of their visible and often explosive development practices, an because Tesla absolutely does play fast and loose with regulations, but for SpaceX it is not just entirely baseless, it's sort of the exact opposite of the truth. When FCC tells SpaceX to jump, SpaceX asks how high on the way up. Demisability standards were among the constraints of their license, so SpaceX made sure to not just meet the requirements, but well exceed them, which is what they always do. Why Musk likes to flout all rules at Tesla and yet follows rules strictly at SpaceX probably as a lot to do with how the regulators are generally pretty toothless about doing anything to Tesla, while either the FCC or the FAA could pretty much shut SpaceX down for as long as they like should SpaceX try to play cute with them. Enforcers with actual ability to enforce rules tend to be respected more.
  - shaklee3 6y ago
    SpaceX absolutely does not follow fcc guidelines. There have been numerous occasions, including changing all their satellites to 550km altitude without getting proper approval where they do it and ask for forgiveness later.
    - Tuna-Fish 6y ago
      > SpaceX absolutely does not follow fcc guidelines. There have been numerous occasions, including changing all their satellites to 550km altitude without getting proper approval where they do it and ask for forgiveness later. No. You have been misinformed, they have always asked for the authorization first. For the orbit modification to 550km, they asked on 2018-11-08, were granted permission on 2019-04-26, and started launching a month after that. [0][1] [0]: https://fcc.report/IBFS/SAT-MOD-20181108-00083 https://fcc.report/IBFS/SAT-MOD-20181108-00083 [1]: https://en.wikipedia.org/wiki/Starlink#Launches https://en.wikipedia.org/wiki/Starlink#Launches
Robotbeat 6y ago
There are multiple reasons, from demisablility to BOM cost and also just that the tech wasn’t quite ready at first and they wanted to launch ASAP to get that minimum viable product up and running (besides their FCC licenses have a time limit for deployment... if they don’t deploy their network fast enough, they can lose access to the spectrum they want to use). They also wanted to be able to bid for broadband subsidies, etc. Lots of good reasons they just launched before the laser links were ready. Also, they don’t necessarily need them except for really, REALLY remote customers (ie a minority), so they can sprinkle in lasers into their constellation as they become available.

by zaroth 6y ago

neaanopri 6y ago

It's probably the BOM cost. I've seen the "burn up in the atmosphere" constraint before, and it struck me as a bit crazy for Shoot First and Ask Questions Later SpaceX to care about this

jccooper 6y ago
Demisability is a significant regulatory concern... but I suspect it wasn't flying before mostly because they didn't have it working yet.
jandrese 6y ago
That requirement could have come from the government. It's not a crazy thing to ask for when you're launching literally hundreds of satellites into LEO. Plus, the last thing SpaceX wants is a news story about killer satellites raining debris on innocent citizens. Remember that each satellite launched has to be deorbited eventually, so if they're launching dozens of sats per month they'll eventually be deorbiting dozens of sats per month. If they don't fully burn up each one will have a chance of hitting someone. Sure the chance may be very small, but when you're rolling the dice dozens or hundreds of times per month eventually you're going to land on snake eyes.
temp667 6y ago
They are explicitly pursuing a demisable sat design. Note - despite other posters claims, this is not a requirement and there are other approaches as well for the safety side here. The most common is to deorbit into the ocean (the sats are maneuverable) with a failure rate and part hazard rate low enough that remaining risk is minimized. I would expect they would deorbit into ocean / near non-populated areas for other reasons as well.
Tuna-Fish 6y ago
> I've seen the "burn up in the atmosphere" constraint before, and it struck me as a bit crazy for Shoot First and Ask Questions Later SpaceX to care about this SpaceX has never been even a little careless about following laws, regulations and staying within the lines of their FCC/FAA authorizations. There is this reputation surrounding them, probably because of their visible and often explosive development practices, an because Tesla absolutely does play fast and loose with regulations, but for SpaceX it is not just entirely baseless, it's sort of the exact opposite of the truth. When FCC tells SpaceX to jump, SpaceX asks how high on the way up. Demisability standards were among the constraints of their license, so SpaceX made sure to not just meet the requirements, but well exceed them, which is what they always do. Why Musk likes to flout all rules at Tesla and yet follows rules strictly at SpaceX probably as a lot to do with how the regulators are generally pretty toothless about doing anything to Tesla, while either the FCC or the FAA could pretty much shut SpaceX down for as long as they like should SpaceX try to play cute with them. Enforcers with actual ability to enforce rules tend to be respected more.
- shaklee3 6y ago
  SpaceX absolutely does not follow fcc guidelines. There have been numerous occasions, including changing all their satellites to 550km altitude without getting proper approval where they do it and ask for forgiveness later.
  - Tuna-Fish 6y ago
    > SpaceX absolutely does not follow fcc guidelines. There have been numerous occasions, including changing all their satellites to 550km altitude without getting proper approval where they do it and ask for forgiveness later. No. You have been misinformed, they have always asked for the authorization first. For the orbit modification to 550km, they asked on 2018-11-08, were granted permission on 2019-04-26, and started launching a month after that. [0][1] [0]: https://fcc.report/IBFS/SAT-MOD-20181108-00083 https://fcc.report/IBFS/SAT-MOD-20181108-00083 [1]: https://en.wikipedia.org/wiki/Starlink#Launches https://en.wikipedia.org/wiki/Starlink#Launches

Robotbeat 6y ago

There are multiple reasons, from demisablility to BOM cost and also just that the tech wasn’t quite ready at first and they wanted to launch ASAP to get that minimum viable product up and running (besides their FCC licenses have a time limit for deployment... if they don’t deploy their network fast enough, they can lose access to the spectrum they want to use). They also wanted to be able to bid for broadband subsidies, etc. Lots of good reasons they just launched before the laser links were ready. Also, they don’t necessarily need them except for really, REALLY remote customers (ie a minority), so they can sprinkle in lasers into their constellation as they become available.