As one of the commenters pointed out, altitude.
A geostationary orbit is ~26,000 miles. Dollars to donuts, that's where it is.
Apple Maps claims it's 29,905 miles away
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Re: Apple Maps claims it's 29,905 miles away
#102While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…
Civilian GPS (as in, the DoD’s Navstar) alone isn’t accurate enough to actually place you on a specific road. To compensate, auto navigation systems will snap you to the nearest road parallel to your current heading. Tesla likely didn’t consider the edge case of ferries and other off road situations in their mapping software and you hit some corner case bug.
This used to be true, but the DoD turned off "selective availability" (the intentional degrading of the civilian signal) back in 2000, and the current generation of satellites do not have the capability (https://www.gps.gov/selective-availability). What they do have though is a separate, encrypted, military broadcast that can be used for those purposes (I think the plan in those situations is to turn off civilian GPS entirely - but I think that there's no reason for that, now, due to the other navigation systems like GLONASS).
Re: Apple Maps claims it's 29,905 miles away
#103Earlier quoted context omitted.
That's no excuse for disbelieving GPS for extended periods of time. Google Maps gets it right: it tried to keep you on road, but only for a few tens of seconds. After that, if you are in the middle of uncharted territory, it'll show the marker there. (This is probably because Google Maps can be used for walking/biking too)
Well, when I’m driving in Kyiv, and there is an air raid alert, usually my car navigation starts to derp, and after a few minutes it thinks that it’s suddenly in Lima, Peru. Not that I mind too much, I know how to get around without navigation.
GPS jamming for incoming drones?
Re: Apple Maps claims it's 29,905 miles away
#104Maybe they are running into https://en.wikipedia.org/wiki/Coastline_paradox
Re: Apple Maps claims it's 29,905 miles away
#105While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…
I had a Volvo XC90 that “jumped” off the interstate and onto a parallel mountain road east of Knoxville. It did its best to track along those roads and somehow made its way into North Carolina. But even when I was back in Chicago, it was still stuck in NC trying to find a way off those mountain roads. Dozens of on/off cycles did nothing. I disconnected the battery overnight and that didn’t work. At the next service a…
In Boston it's a very frequent occurrence to be driving in the Central Artery Tunnel and have your map software think you're on the surface, or vice versa, or to be on a highway overpass and again have it think you're on a surface road that is inaccessible from your location. You get used to it.
This seems like an entirely different level of craziness, though.
Re: Apple Maps claims it's 29,905 miles away
#106While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…
Back in the days of MapQuest there was a (usually) very good site called mapsonus.com, but it evidently had one of the ferries that crossed Boston Harbor in its map as a zero distance link.
Since it was offline, the bug was obvious although a bit frustrating - you had to put in multiple waypoints to make it forget its urge to send you on the ferry to Hull when you were trying to get to parts of the South Shore.
Re: Apple Maps claims it's 29,905 miles away
#107Earlier quoted context omitted.
I had a Volvo XC90 that “jumped” off the interstate and onto a parallel mountain road east of Knoxville. It did its best to track along those roads and somehow made its way into North Carolina. But even when I was back in Chicago, it was still stuck in NC trying to find a way off those mountain roads. Dozens of on/off cycles did nothing. I disconnected the battery overnight and that didn’t work. At the next service a…
In Boston it's a very frequent occurrence to be driving in the Central Artery Tunnel and have your map software think you're on the surface, or vice versa, or to be on a highway overpass and again have it think you're on a surface road that is inaccessible from your location. You get used to it. This seems like an entirely different level of craziness, though.
Yeah I remember back in the early 2000s before phones had turn-by-turn navigation, there were PDAs to do it and it was common for the software to just ask whether you were driving on the surface road or an elevated viaduct.
Re: Apple Maps claims it's 29,905 miles away
#108Earlier quoted context omitted.
I had a Volvo XC90 that “jumped” off the interstate and onto a parallel mountain road east of Knoxville. It did its best to track along those roads and somehow made its way into North Carolina. But even when I was back in Chicago, it was still stuck in NC trying to find a way off those mountain roads. Dozens of on/off cycles did nothing. I disconnected the battery overnight and that didn’t work. At the next service a…
My dad used to have a crappy aftermarket GPS in his car that did the same thing. It would get lost dozens of miles away, and then hundreds of miles away. The explanation I found online at the time was that a GPS receiver needs to download data about the exact orbits of all GPS satellites from time to time. Satellites slowly lose altitude and change their orbits. Up-to-date information is constantly broadcasted by eve…
That's only the case for non-internet connected GPS units. Throwback to the early 2000s when my family car had such a unit, which, after having been turned on, would require ~15 minutes of waiting before it became functional. Funnily, I remember the mapping app would refuse to use the device clock and only use the time from GPS satellites. So at least you would know you need to wait if it didn't know the current time.
Re: Apple Maps claims it's 29,905 miles away
#109Earlier quoted context omitted.
That's no excuse for disbelieving GPS for extended periods of time. Google Maps gets it right: it tried to keep you on road, but only for a few tens of seconds. After that, if you are in the middle of uncharted territory, it'll show the marker there. (This is probably because Google Maps can be used for walking/biking too)
> That's no excuse for disbelieving GPS for extended periods of time. You've got it backwards. I was explaining why GPS should take priority over mapping data. Not the other way around.
They’re saying that not prioritising (disbelieving) GPS data is bad, hence there’s no excuse for it
So that’s the same thing you’re saying
Re: Apple Maps claims it's 29,905 miles away
#110Earlier quoted context omitted.
That's no excuse for disbelieving GPS for extended periods of time. Google Maps gets it right: it tried to keep you on road, but only for a few tens of seconds. After that, if you are in the middle of uncharted territory, it'll show the marker there. (This is probably because Google Maps can be used for walking/biking too)
>(This is probably because Google Maps can be used for walking/biking too) Please don't do that. The map is simply not good enough and does not have enough context (road quality, terrain, trail difficulty) for anything but very causal activity. Even then I highly recommend to use a proper map, electronic or paper.
Trail? Terrain? I use it for walking for 10-20mins around a (mostly flat) city and I expect that’s what 90% of people use it for, the comment didn’t mention hiking