Cool Worlds
4 HN recommenders · recommended in 8 months, 2020–2025
29:52 · 613K views · Aug 2, 2019
David Kipping presents his proposed Terrascope, a telescope that uses Earth's atmosphere as a lens to achieve enormous magnification. He covers the history of telescopes and his path to the idea, plus Sol-scope and Jupiter-scope variants.
HN people point to it as an excellent explanation of using Earth's atmosphere or gravity as a lens in astronomy threads.
10 comments from Hacker News
I love the idea of using gravitational lensing of the sun from a lagrange point around Jupiter. IIRC it theoretically could image an earth like planet in the region of 1000px x 1000px so you could see continents and weather systems - perhaps even light from large cities. I watched a great "Cool Worlds" video as well that said you could do similar with atmospheric lensing of the earth from a lagrange point near the moon (although it would filter out some visible light wavelengths and be weather dependant) - but potentially a much cheaper mission: this video This would be going full circle in terms of telescope technology, we started with lenses, moved to mirrors and now back to lenses! To me these seem like the most exciting missions ever - could define a new epoch for humanity and inspire and excite hundreds of millions of people. I would be very disappointed if this didn't happen in my life.
You might be interested in this video which talks about using the Earth's gravity to create a telescope with a lens roughly the size of the Earth (a terrascope): this video They also have a follow up video about using Jupiter to create a jovoscope and there's also more about creating a telescope using the sun (although since the sensor would need to be so far away from the Sun, we would essentially need to launch a different spaceship for each target that we tried to image).
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: [LINK] You can also use Earth's atmosphere as a lens too! It's an amazing video: this video Going even crazier, I can imagine we could some day use a massive black hole as a giant telescope.
Need many images to superimpose them into a single computed image. David Kipping has a great video on it this video We would need a train of probes being sent in a row because there is a limited amount of time they will pass through the focal area.
An excellent video on this: this video Earths atmosphere and weather affects this sort of telescope IIRC and will filter out some lightwaves but seems like a much easier win