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JWST reveals its first direct image discovery of an exoplanet

(www.smithsonianmag.com)
342 points divbzero | 2 comments | 27 Jun 25 17:44 UTC | HN request time: 0.463s | source
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GMoromisato ◴[27 Jun 25 23:00 UTC] No.44401068[source]▶
In case anyone is wondering, we are (sadly) very far from getting an image of this planet (or any extra-solar planet) that is more than 1 pixel across.

At 110 light-years distance you would need a telescope ~450 kilometers across to image this planet at 100x100 pixel resolution--about the size of a small icon. That is a physical limit based on the wavelength of light.

The best we could do is build a space-based optical interferometer with two nodes 450 kilometers apart, but synchronized to 1 wavelength. That's a really tough engineering challenge.

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GolfPopper ◴[28 Jun 25 00:05 UTC] No.44401398[source]▶
We can do better than that! Using the Sun as a gravitation lens[1], and a probe at a focal point of 542 AU, we could get 25km scale surface resolution on a planet 98 ly away. [2] This would be an immense and time-consuming endeavor, but does seem to be within humanity's current technological capabilities.

1. https://en.wikipedia.org/wiki/Solar_gravitational_lens

2. https://www.nasa.gov/general/direct-multipixel-imaging-and-s...

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1. j_not_j ◴[28 Jun 25 14:12 UTC] No.44404832[source]▶
Wouldn't be worth the trouble to try.

Why, you ask?

How do you point it? Where do you point it?

You have a "telescope" with a field of view of one-planets worth of pixels. But the planet is in orbit, so it drifts away from the imaged field of view within minutes.

Meanwhile your sensor is travelling away from the "lens" so transverse velocity would be needed to track the orbit at a delta-v and direction that is unknowable. Unknowable, because you have to know where the planet is, within a radius, to put your "sensor" in the right place in the first place.

Imagine taking a straw, place it in a tree, walk away a few km and focus a telescope on the straw and hope to look through the straw to see an airplane flying past. You have the same set of unknowables.

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2. __MatrixMan__ ◴[28 Jun 25 15:08 UTC] No.44405211[source]▶
I won't argue that it would be worth the effort, but it would be interesting to set something like that going and just keep scanning. A few years worth of data might turn up interesting things even if it wasn't particularly useful for finding those things a second time.