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Comment by ldargin | Hacker News Reader

Our telescopes and other instruments are getting more powerful. All we have to do is look...

That's not that useful. It's great for looking back in time to see the origins of the universe, but if you want to communicate with someone on a planet 100 light-years away, that's a 200-year round-trip latency. And telescopes will likely never be powerful enough to see, for instance, the actual inhabitants of another planet (we'd be lucky if we could see some gigantic Death Star-sized space station optically).

>And telescopes will likely never be powerful enough to see, for instance, the actual inhabitants of another planet (we'd be lucky if we could see some gigantic Death Star-sized space station optically).

gravitational lensing by Sun, just need to put the telescope at least 550 AU from the Sun.

https://www.airspacemag.com/daily-planet/ultimate-space-tele...

"And using the Sun as a lens would result in much greater magnification. Instead of a single pixel or two, astronomers would get images of 1,000 x 1,000 pixels from exoplanets 30 parsecs, or about 100 light years, away. That translates to a resolution of about 10 kilometers on the planet’s surface, better than what the Hubble Space Telescope can see on Mars, which would allow us to make out continents and other surface features."

To the GGP point of light speed limit - that is only true for static fixed spacetime. The spacetime expansion/contraction doesn't seem to have that limit (this is how we have far-far galaxies receding from us at the speeds higher than c). Just an issue of engineering that into a practical drive ...

By definition, if we can extend our lifespans long enough for a person to travel 100 light years, we can wait the 100 years it takes for a signal to arrive.

You're not going to have a very good conversation with a 200-year latency. A normal conversation requires many messages on both sides. 1 year isn't that much of a human lifespan, but if we tried to hold a conversation with a 1-year round-trip latency, it's not going to be a very good conversation; it's just too long between messages. But if you just want to blast them with a ton of information all at once (like sending them a bunch of video archives and a copy of Wikipedia, for instance), that's doable, but it's not a conversation.

They are similarly limited by light speed (in the other direction)

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