Get the location of the ISS using DNS

Posted by 8organicbits 7/6/2025

Get the location of the ISS using DNS(shkspr.mobi)

342 points | 90 commentspage 2

pvtmert 7/6/2025|

Besides the hard-coded cache, shouldn't DNS infrastructure already help with the caching just by the TTL value itself? Given quite many & large public DNS resolvers out there, like Cloudflare's 1.1.1.1 and Google's 8.8.8.8

I overall like the DNS, it is a global database with eventual consistency. Possible to store transient data. Usually not blocked by firewalls just by the sheer innocent nature. (Although gets intercepted quite a lot...)

xyst 7/6/2025||

Great post, definitely something I can setup on my personal recursive DNS resolver. Yet another toy I can throw on to my rpi :)

huslage 7/6/2025||

Could you calculate the position from the Ephemeris data in realtime instead of using an API? This would allow you to return the current location on every request potentially.

ygritte 7/7/2025||

Remember, kids, you can only measure either the location, or the spin. If you do both, the ghost of Werner Heisenberg will come to haunt you.

jamesgill 7/6/2025||

OpenNotify is another (more limited, less fancy) resource: http://open-notify.org/

timzaman 7/6/2025||

"~instantly! (...) every 15 minutes" - omg

lordnacho 7/6/2025||

Is there any service on the ISS that the public can interact with? Maybe you could use response times to figure out where it is that way.

Maxious 7/6/2025||

There's quite a few amateur radio frequencies you can interact with https://issfanclub.eu/iss-frequencies/

trothamel 7/6/2025||

It's pretty likely there will be a slow-scan TV event in mid-July, where the station will be transmitting images you can pick up with a radio. These are nice because you don't neeed a license - anyone with a radio that can pick up the right frequencies can receive.

crazygringo 7/6/2025|||

That's what I thought this was going to be from the title -- some kind of DNS response time triangulation from a device on the ISS itself, because DNS was allowed past a firewall or something...

It's still a fun little project, but definitely feeling a little disappointed in comparison to what the title felt like it suggested to me...

croes 7/6/2025||

Depends on the hops between you and the target

IndrekR 7/6/2025||

Considering the ISS orbits in ~90 minutes, the 15 minute TTL is quite a long time.

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