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Very cool, but very dependent on weather too. Imagine your satellite can't send data because there is cloud cover... In some parts of the world that may last fo

Very cool, but very dependent on weather too. Imagine your satellite can't send data because there is cloud cover... In some parts of the world that may last for 6 months.

defrost 3y ago
Good point to be sure but a little Yes and No - no one is planning on building a space comms station in a PNG valley obscured by clouds - typically they've been built in good weather locations (eg: > Optical Ground Station 1 in Table Mountain, California. > The location was chosen for its clear weather conditions and remote, high altitude. [1] ) and the application for ground based comms will largely be from mountain top to mountain top for long legs across rough cable laying defying territory. Moreover recent developments have seen much better cloud piercing abilities - both in frequencies used and from better real time "de turbulance" filters that can reconstruct what cloud based particles tear asunder [2]. [1] https://www.nasa.gov/sites/default/files/atoms/files/tbird_fact_sheet_v2.pdf https://www.nasa.gov/sites/default/files/atoms/files/tbird_f... [2] https://www.raytheonintelligenceandspace.com/news/2020/07/15/laser-comms-cuts-through-clouds https://www.raytheonintelligenceandspace.com/news/2020/07/15...
JoeDaDude 3y ago
The solution the satellite world has developed for dealing with precipitation absorption of Ka-band and higher frequencies might apply to lasercomm and clouds. In the Ka-band case, having multiple potential downlink sites provides good probability that at least one of them has weather conditions suitable to support the downlink.
toomuchtodo 3y ago
The solution is driving down the cost of base stations and having many of them, similar to how Starlink has a large network of downlink stations colocated at fiber meetups. https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html
- jandrese 3y ago
  This is the part of Starlink that gets very little fanfare but is one of the more impressive parts of the system. Early skeptics pointed out that not only had no satellite company ever launched anywhere close to that many satellites, but that ground stations tended to be extremely expensive to maintain (tens of millions of dollars per year per station) and were few in number, but Starlink was proposing to build thousands of them. A lot of the old guard thought that if the satellite launch costs didn't kill them the ground station maintenance would. But Starlink proved that it was mostly an "old space" problem and there was no fundamental reason the ground stations had to be so outrageously expensive.

Very cool, but very dependent on weather too. Imagine your satellite can't send data because there is cloud cover... In some parts of the world that may last for 6 months.

defrost 3y ago

Good point to be sure but a little Yes and No - no one is planning on building a space comms station in a PNG valley obscured by clouds - typically they've been built in good weather locations (eg: > Optical Ground Station 1 in Table Mountain, California. > The location was chosen for its clear weather conditions and remote, high altitude. [1] ) and the application for ground based comms will largely be from mountain top to mountain top for long legs across rough cable laying defying territory. Moreover recent developments have seen much better cloud piercing abilities - both in frequencies used and from better real time "de turbulance" filters that can reconstruct what cloud based particles tear asunder [2]. [1] https://www.nasa.gov/sites/default/files/atoms/files/tbird_fact_sheet_v2.pdf https://www.nasa.gov/sites/default/files/atoms/files/tbird_f... [2] https://www.raytheonintelligenceandspace.com/news/2020/07/15/laser-comms-cuts-through-clouds https://www.raytheonintelligenceandspace.com/news/2020/07/15...

JoeDaDude 3y ago

The solution the satellite world has developed for dealing with precipitation absorption of Ka-band and higher frequencies might apply to lasercomm and clouds. In the Ka-band case, having multiple potential downlink sites provides good probability that at least one of them has weather conditions suitable to support the downlink.

toomuchtodo 3y ago

The solution is driving down the cost of base stations and having many of them, similar to how Starlink has a large network of downlink stations colocated at fiber meetups. https://eyes.nasa.gov/dsn/dsn.html https://eyes.nasa.gov/dsn/dsn.html

jandrese 3y ago
This is the part of Starlink that gets very little fanfare but is one of the more impressive parts of the system. Early skeptics pointed out that not only had no satellite company ever launched anywhere close to that many satellites, but that ground stations tended to be extremely expensive to maintain (tens of millions of dollars per year per station) and were few in number, but Starlink was proposing to build thousands of them. A lot of the old guard thought that if the satellite launch costs didn't kill them the ground station maintenance would. But Starlink proved that it was mostly an "old space" problem and there was no fundamental reason the ground stations had to be so outrageously expensive.