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JWST reveals its first direct image discovery of an exoplanet

(www.smithsonianmag.com)
342 points divbzero | 1 comments | 27 Jun 25 17:44 UTC | HN request time: 0.001s | 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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bravesoul2 ◴[27 Jun 25 23:22 UTC] No.44401184[source]▶
L2 is moving though right? Or does it need to be simultaneously receiving at the 2 points?
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GMoromisato ◴[27 Jun 25 23:33 UTC] No.44401252[source]▶
Sadly, it has to be simultaneous.

My (tenuous) understanding of interferometry is that you receive light from two points separated by a baseline and then combine that light in such a way that the wavelengths match up and reinforce at appropriate points.

Wikipedia has a decent summary: https://en.wikipedia.org/wiki/Aperture_synthesis

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1. littlestymaar ◴[29 Jun 25 20:59 UTC] No.44416380{3}[source]▶
> Sadly, it has to be simultaneous.

I don't know the details of how it works, but synthetic aperture radar works thanks to the motion of the satellites, so there must be some situations for which simultaneity isn't required.