system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If we can look 1400 light years away to find another earth-like planet, what's stopping us from zooming in just a little closer to look for indications of life forms?
gpt
You're confused on how we find earth-like planets. We don't actually see them. No telescope ever made can see that far with that much detail. Instead we look at the amount of light a given star produces, and if it wiggles back and forth. When a planet travels in front of it's star, the light drops off a tad bit. The star will also wiggle back and forth from the gravity of the circling planet. These are two methods used to detect other planets. 

Tldr; We don't "see" the other planet, instead we look for indicators from the star that there are planets in the system.