You can pretty much make a telescope as large as you'd like, depending on your technological level. Hypothetically, you can use gravitational lensing to make a

You can pretty much make a telescope as large as you'd like, depending on your technological level. Hypothetically, you can use gravitational lensing to make a telescope via the sun! It's rather unfeasible at our current level of rocketry, but in time, maybe! Article: https://blogs.scientificamerican.com/observations/using-the-sun-as-a-cosmic-telescope/ https://blogs.scientificamerican.com/observations/using-the-... You can also use Earth's atmosphere as a lens too! It's an amazing video: https://www.youtube.com/watch?v=jgOTZe07eHA https://www.youtube.com/watch?v=jgOTZe07eHA Going even crazier, I can imagine we could some day use a massive black hole as a giant telescope.