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Re:SpaceX sends laser-linked Starlinks to the polar orbit by iso1631 on Monday January 25, 2021 @03:21PM (#25908231)
Not just low latency. Without satelite-satelite communication, both grounds stations have to be able to see the same satellite.

In GEO that's not a problem - a lot of the planet is in sight. You have a ground station in New York and you can bounce off a satellite over the Atlantic and land the signal in Nigeria just fine.

With Starlink the orbits are really low, so the distance to the ground station is low. That's fine if you are in the backwoods in Washington and bounce to a receiving station 100 miles away in Seattle, it's no good if you're at sea, or (in this case) at an Antarctic station -- one which can't even see GEO satelites.

Re:SpaceX sends laser-linked Starlinks to the polar orbit by walrus01 on Monday January 25, 2021 @03:31PM (#25908377)
big chunks of antarctica where most of the research base population is located can see geostationary, just at a very low look angle. the whole peninsula, mcmurdo and places at similar latitudes to mcmurdo.

it's the pole that has problems seeing geostationary, and has up until very recently been totally dependent on 7-8 hours of coverage a day using big tracking antennas to talk to old geostationary satellites that have wandered somewhat out of their original orbits, so that from the POV of the earth station at pole, they can be communicated with part of the time.

Re:SpaceX sends laser-linked Starlinks to the polar orbit by snoshy on Monday January 25, 2021 @05:41PM (#25909945)
Yea I'm guessing a bunch of researchers at both poles must be rejoicing at the potential for new connectivity this creates with the polar launch.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by cozzyd on Tuesday January 26, 2021 @12:44AM (#25912967)
Not sure if they'll get a Starlink terminal down there this season, especially given COVID-19 restrictions in New Zealand.

Most data and internet from pole is via ~4 hours of DSCS a day, ~4 hours of skynet (slowww...) or when TDRSS decides to gives South Pole time (but in small chunks of time).

I usually try to ssh in my experiment at Pole the start of DSCS time, which unfortunately can be in the middle of the night for me.

Re:SpaceX sends laser-linked Starlinks to the polar orbit by walrus01 on Monday January 25, 2021 @05:47PM (#25909996)
The US DoD and Soviets, Russians somewhat solved this problem by putting molniya/tundra orbit communications satellites into orbit for narrowband data and voice, text comms. Has been a thing for 35+ years.

But there has been nowhere near enough money available to do something like set up a pair of molniya orbit satellites with long apogee dwell times over the center of antarctica.

Re:SpaceX sends laser-linked Starlinks to the polar orbit by snoshy on Monday January 25, 2021 @06:05PM (#25910185)
Sure, but that pittance of bandwidth is a far cry from having persistent 24/7 access to a high bandwidth, low latency service like Starlink. Long boring months spent in the darkness with very few recreational outlets now all of a sudden become a lot more attractive with access to the open Internet and your loved ones with no restrictions.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by walrus01 on Monday January 25, 2021 @06:09PM (#25910220)
I can only imagine. For the Amundsen-Scott station people I imagine it will be revolutionary.

Assuming that the topology will be additional highly-inclined/polar orbit starlink satellites, communicating with each other in a laser chain, this will be dependent on starlink setting up earth stations near fiber somewhere in southern Chile, Argentina or in South Africa. Or south australia, tasmania, new zealand.

Re:SpaceX sends laser-linked Starlinks to the polar orbit by hifly on Monday January 25, 2021 @07:11PM (#25910734)
Iridium already cover the poles? You can get 700kbit down and bonding terminals is a possibility.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by walrus01 on Monday January 25, 2021 @07:53PM (#25911073)
That's true, though real world performance is often more like 350kbps. The Iridium NeXT series satellites and second generation network are a fairly recent thing to go into production use in the past couple of years, before that, an individual iridium terminal was limited to about 2400 bps with v42bis compression. There were some famously weird multilink PPP bonding solutions used in Antarctica with four separate Iridium modems and antennas.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by snoshy on Monday January 25, 2021 @08:39PM (#25911377)
Aside from the fact that Starlink connections are or two orders of magnitude better in throughput and latency, the biggest problem with Iridium is the cost. It's just simply out of the realm of affordability just for the likes of streaming some videos or playing games in their off-time.

Now that I think about it though, the Starlink user terminals likely won't be able to survive the harsh winters at the poles. -30 deg C and low tolerance for high winds means this would be tough unless some type of non-obstructive sheltering could be provided.

Re:SpaceX sends laser-linked Starlinks to the polar orbit by walrus01 on Monday January 25, 2021 @10:11PM (#25912003)
I imagine that compared to the fully-loaded cost per hour of Amundsen-Scott station just to exist, be periodically resupplied, pay salaries of staff, buy equipment, transport logistics...

Even if you maintained multiple $1.25 per minute (or $5 per megabyte) Iridium links, operating 24x7x365, it would be a teensy tiny drop in the bucket compared to the total budget of the station.

Re:SpaceX sends laser-linked Starlinks to the polar orbit by cozzyd on Tuesday January 26, 2021 @12:46AM (#25912978)
Sure, NSF is willing to pay for bandwidth that is used to transmit science data. Less so for people wanting to watch cat videos at Pole :).
Re:SpaceX sends laser-linked Starlinks to the polar orbit by namibj on Monday January 25, 2021 @10:58PM (#25912343)
They'll just stick it under a radome.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by cozzyd on Tuesday January 26, 2021 @12:47AM (#25912987)
I believe Iridium Certus is being tried out at Pole right now, but was not an option (for me) when I was there ~1 year ago.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by Gravityloss on Monday January 25, 2021 @03:30PM (#25908368)
The field of view from the satellite is 5000 km, though reception probably gets a lot worse at lower angles for a multitude of reasons. Hope I calculated right.

https://www.wolframalpha.com/input/?i=2*6300*arccos%286300%2...

Re:SpaceX sends laser-linked Starlinks to the polar orbit by walrus01 on Monday January 25, 2021 @03:32PM (#25908391)
the starlink beta test customer terminals only have a cone shaped view of suitable beam forming ability and gain above them, so the 4000 km is a lot less in usable practice. they can't talk to a satellite that's 15-20 degrees above the horizon for instance, it'll only work when the satellite rises higher in its general field of view.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by namibj on Monday January 25, 2021 @10:59PM (#25912355)
The horizon limitation is primarily regulatory. Given that limitation, it doesn't make sense for them to extend the cone closer to the horizon than their flat phased array can do.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by shaklee3 on Tuesday January 26, 2021 @12:38AM (#25912933)
Not true. The antenna itself has a very low scan to keep costs down.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by namibj on Tuesday January 26, 2021 @01:02AM (#25913054)
Yes, because e.g. a multi-panel design would be limited by regulations. Hence they decided on the single panel for ROI/cost-efficiency purposes.
Re:SpaceX sends laser-linked Starlinks to the polar orbit by walrus01 on Tuesday January 26, 2021 @12:59AM (#25913040)
Indeed, a flat phased array can only have a certain limited gain at elevations and azimuths far away from the direction it's pointed in. One of the reasons if you ever see a flat phased array radar inside the nose radome of a air superiority type fighter jet, they're not fixed but also can be mounted on a sort of pan/tilt platform for steering.