[HN Gopher] Realtime Starlink Satellite Map
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Realtime Starlink Satellite Map
Author : deegles
Score : 67 points
Date : 2020-06-17 19:59 UTC (3 hours ago)
(HTM) web link (satellitemap.space)
(TXT) w3m dump (satellitemap.space)
| ruslan wrote:
| Is there any decent resource explaining how the whole mesh of
| Starlink sattelites communicate to each others and to the ground
| ? Do they use RF radio or modulated laser ? What equipment should
| be used by end users and what frequency range ?
| modeless wrote:
| Details are here:
| https://licensing.fcc.gov/myibfs/download.do?attachment_key=...
|
| TL;DR User terminals are RF phased array antennas. Ka-band and
| Ku-band, plus E-band for ground stations. v1 has no cross
| satellite links. Plans for v2 include laser cross links.
| ruslan wrote:
| Ok, thanks. Designing a DYI terminal won't be easy for these
| bands.
| verandaguy wrote:
| Holy Kessler Syndrome, Batman!
| LeoPanthera wrote:
| This is specifically not a concern for Starlink, which is in an
| extremely low orbit. Dead satellites (and any theoretical
| debris) would deorbit and burn up in less than 5 years. End-of-
| life satellites are intentionally deorbited immediately.
|
| Additionally, the starlink satellites perform active collision
| avoidance.
| chundicus wrote:
| I could make some guesses, but can someone give me a good answer
| as to why there aren't any of these satellites close to the
| poles?
| Pfhreak wrote:
| It's a relatively big surface area increase and a relatively
| small customer count increase?
| upofadown wrote:
| A satellite orbit has an inclination. If you launch it lined up
| with the equator then it will always stay over the equator. So
| you choose how far the satellite will wander north and south by
| adjusting the inclination at launch. The less the inclination
| the fewer satellites you need for coverage. So it is a
| tradeoff. Obviously the decision was made to only cover up to
| the place that population density falls off in the northern
| direction.
|
| Added: Because the satellites spend more time at the northern
| and southern extremes they get denser coverage there. That is
| likely why they are initially offering coverage near the
| US/Canada border.
| mhandley wrote:
| All the satellites in the first phase of Starlink are in 53
| degree inclination orbits. This will give them coverage from
| about 60 degrees North down to 60 degrees South. In later
| phases they plan to have satellites in higher inclination
| orbits, but in the early stages, there just aren't enough
| people living that far North (sorry Scandinavia, you'll have to
| wait) for it to be worth spending 30% of the satellites' time
| over the poles when they can be over more populated parts of
| the planet instead.
| modeless wrote:
| There will be in v2. In v1 there's no point because the
| satellites don't have cross links, so they can only provide
| service while in range of a ground station, and there won't be
| any ground stations at the poles.
| nickik wrote:
| Mainly because there are no costumers there. If you want to
| cover the poles, you totally could but its just not necessary.
| [deleted]
| aphextron wrote:
| Seems like a huge footprint for each satellite to service. Dense
| metro areas are really getting the shaft here. Any data on the
| backhaul capacity?
| wmf wrote:
| Starlink just isn't for dense areas.
| est31 wrote:
| In internet coverage, like with most infrastructure, there are
| power laws. I'm making up numbers but it's like connecting the
| first 50% costs as much as connecting the last 5%. Starlink is
| for those 5% who live in extremely remote areas.
| mhandley wrote:
| This map seems to have some inaccuracies. I'm not sure what the
| circles are supposed to be, but they're wrong for the satellite's
| coverage limits - looks like they're shown at about half of the
| actual 940km coverage radius. It also looks like their altitude
| is incorrect - the ones in operational orbits are at 550km.
| Eyeballing this map, it looks like they're shown at something
| like 1/3 to 1/2 of that - certainly much lower than they should
| be.
| wcoenen wrote:
| In the /about it's explained that the circle represents the
| locations where the satellite is at least 60 degrees above the
| horizon.
|
| 550 km is the altitude for the operational orbits, the
| satellites are deployed lower and need to raise their orbit.
| (But I see most are labeled around 550 km, so I'm not sure what
| you're referring to.)
| mhandley wrote:
| The SpaceX FCC filings indicate reachability down to 25
| degrees above the horizon, so it's not clear why 60 degrees
| was chosen in this animation.
|
| I do understand that the satellites are deployed into lower
| orbits, but satellites from launches 1, 2 and 3 (and some of
| launch 4) are now at 550km:
|
| https://twitter.com/StarlinkUpdates/status/12732692201308610.
| ..
|
| Those launches are shown way too low in this map. From
| measuring pixels, I make them to be roughly 200km.
|
| Edit: maybe I'm being pedantic here, but the combination of
| showing artifically small coverage zones, plus showing
| satellites much lower than they are so giving a misleading
| impression of how much area each satellite can see, taken
| together give the misleading impression that Starlink
| coverage will be worse than it will actually be.
| LeoPanthera wrote:
| Possibly intentionally misleading, the author makes several
| disparaging comments of Starlink at the bottom of /about
| advisedwang wrote:
| > Opinion > No evidence a working starlink network can offer
| lower latency, or lower prices, than terrestial > > Impact on
| earth based telescopes has not been discussed > > Starlink is a
| play for pentagon funding to keep SpaceX launch schedule busy?
|
| Author doesn't seem to have any love for Starlink. I wonder why
| the built the site.
| modeless wrote:
| That's strange. All of those points are wrong anyway.
|
| Starlink isn't designed to offer lower latency or lower prices
| than existing terrestrial wired or wireless ISPs (at least,
| decent ones). Instead it's designed to offer a low latency
| wireless service in places where that has never been available
| at all. Which is most of the land area of the Earth, and all of
| the ocean. It may also be cheaper and/or faster than some very
| bad terrestrial ISPs, because there are a lot of those out
| there, but that's not what it's designed for.
|
| Impact on earth-based telescopes has been discussed endlessly,
| to the point where it seems like there's a law that you can't
| mention Starlink on the Internet without talking about it. And
| SpaceX responded by talking to the astronomers most affected by
| Starlink and designing a sunshade that should prevent the
| satellites from ruining their images. Which is more than any
| other satellite operator has ever done, AFAIK, and there are
| many satellites much brighter than Starlink in the sky today.
|
| The Pentagon is certainly interested in Starlink, but
| commercial service will be the bigger part of revenue. There
| are several competitors planning to do roughly the same thing
| as Starlink, so the business plan is at least plausible.
| watersb wrote:
| Radio Astronomy has to deal with this, never mind the sun
| shades. Pervasive radio everywhere has been a growing problem
| in general at least since GPS.
| jbuzbee wrote:
| Vey interesting analysis of Starlink coverage and latency:
|
| https://www.youtube.com/watch?v=m05abdGSOxY
| bryanlarsen wrote:
| Starlink will has promised better latency, bandwidth and
| prices compared to existing satellite internet. Perhaps
| that's where the confusion on the first point came from.
| arcticfox wrote:
| I'm really confused what is going on here.
|
| It's really baffling how someone motivated and talented
| enough to make such a tracking site would have such an odd
| opinion section.
|
| Obviously, Starlink is not the best choice in all
| situations, but it is so compelling on some dimensions that
| such a flatly negative opinion is bizarre for anyone with
| even a cursory understanding of what's going on.
| noxer wrote:
| LMAO saw that too an got my daily does of conspiracy theories.
| thoraway1010 wrote:
| What's funny is if you go sailing on the ocean for extended
| periods (months) you realize that sat data / phone costs are
| RIDICULOUS in this age. $3 - $5/MB. So your 4 GB movie is
| $20,000. You'd think, why would anyone pay this, but there can
| be a lot of pressure these days to be able to send videos etc
| so you sometimes get jammed up with these types of costs (ie,
| if you do a telemedicine call the DR may want a video of joint
| movement etc etc, recreational trips people want to post videos
| and don't realize their phone records at pretty large file
| sizes etc etc).
|
| So if they can do better just on COST then this it would be
| wonderful.
| ccmcarey wrote:
| We used a sat link for getting the latest weather
| information, though you can also get that frequently on
| V(HF), so .. not terribly useful. But, terribly slow and
| unreliable (Iridium).
| scohesc wrote:
| That's what I probably misunderstand about the technology - I
| don't understand how you can have lower latency than current
| WISP-based infrastructure (are they making these claims against
| ground-based infrastructure?) when there's satellite internet
| connections that fade out when a cloud goes by... Also, I would
| assume they'd have massive capacity issues if they're planning
| on over-subscribing (they'd have to if they want to sustain a
| viable profit model, unless they're surviving on government
| funding?)
| entropicdrifter wrote:
| They're claiming lower latency than existing satellites due
| to lower altitude orbits and are using more satellites to
| compensate for the decreased coverage from each satellite.
|
| Presumably this setup would also help with the cloud coverage
| issue due to the shorter travel distance and higher
| likelihood of redundant satellites to connect to.
| kitsunesoba wrote:
| To be more precise, some of the lowest flying Starlink
| satellites will be at 340km, which is very low -- lower
| than the ISS, even. By contrast, traditional internet
| satellites orbit at ~35,700km.
| nyx_ wrote:
| 550km, actually, or 340 miles. Still a couple orders of
| magnitude closer to Earth than satellites in GSO.
| modeless wrote:
| v2 is planned to have satellites as low as 328 km. https:
| //licensing.fcc.gov/myibfs/download.do?attachment_key=...
| the8472 wrote:
| Their competition are geostationary satellites that have high
| latency due to speed of light delays.
|
| In theory a LEO satellite network could also beat
| transoceanic fiber connections since the high refractive
| index causes the speed of light in fiber to be only ~2/3rds
| the vacuum speed of light. But that would require satellite-
| to-satellite optical links which the first generation of
| starlink doesn't have.
| bryanlarsen wrote:
| The speed of light in a vacuum is about 50% faster than the
| speed of light in glass.
|
| But that requires the inter-satellite links be viable, which
| they aren't yet: the required lasers would survive reentry
| and they want the satellites to burn up completely on de-
| orbit so current versions of the satellites don't have them.
|
| And yes, there are significant capacity limitations. Only the
| truly rural will get good data rates.
| MojoLobo wrote:
| That would explain why there are dense clusters of satellites
| over middle-of-nowhere oceans, but they're sparse over
| continents, particularly Asia and Africa.
|
| They're probably going after a different market?
| bryanlarsen wrote:
| The satellites orbit the earth every 1.6 hours. They're not
| in geo-stationary orbit, they're in very low earth orbit to
| reduce latency. And any orbit will spend a significant
| portion of it's time over water.
|
| Also, only the green circled satellites are in their final
| orbit, the yellow circled ones were recently launched and are
| not yet at their final altitude and position. It takes a
| couple of months for orbit raising.
| MojoLobo wrote:
| Ah, thanks for clarifying. I just assumed for some reason
| they were geostationary satellites.
| makomk wrote:
| Yeah, as I understand it the current generation of Starlink
| satellites are likely to be pretty much unusable when
| they're over the ocean since they need to have line of
| sight to a ground station.
| aeyes wrote:
| They might be usable for airplanes, ships, oil platforms,
| islands...
| zaphoyd wrote:
| without interlinks an airplane, ship, oil platform, or
| island could talk to the starlink sat, but the sat
| couldn't talk to its ground base station to forward their
| messages to the rest of the internet. Coverage for deep
| ocean will require a second generation that can talk sat
| -> sat.
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(page generated 2020-06-17 23:00 UTC)