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Comment by blakesterz | Hacker News Reader

Is this the kind of thing they'll be able to point the James Webb Telescope at and say "Aha, here's what this thing is!" ? I don't know enough about the James Webb Telescope or astronomy to know what it's going to be looking at, but I know it was something about light spectrum or something.

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If you're asking whether we could image the actual magnetar (assuming that's what they observed) with JWST, the answer is no. If it's a magnetar, the object itself is less than 100 km in diameter. JWST has an angular resolution of about .1 arc seconds, which at 4000 light years distance means it can resolve things that are billions, not tens, of kilometers (think the size of Pluto's orbit) in extent. The magnetar is probably also dark in the infrared spectrum JWST can see well.

Think Hubble could do the same since it so close. My basic understanding is James Webb is better suited for ultra deep space observations, because it doesn't care about dust as much.

No, the reason JWST is better for ultra deep space is because the expansion of the universe redshifts the peak of the light emitted by the really old stars into the IR band. Also it has a bigger mirror so it can see fainter stuff, which things further away tend to be.

No, this is a radio source and JWST is primarily an infrared observatory.

That we've detected a radio source doesn't mean there's not something there in infrared as well, though.

No that's the entire point of calling it a 'magnetar'. These things convert the magnetic field into radio waves. That's the only thing that is being emitted and 'observable'. This specific specimen matches a theoretical variant that has an ultra long cycle.

That doesn't mean there's nothing to see.

Here's a magnetar imaged with infrared via the Spitzer telescope: https://www.spitzer.caltech.edu/image/ssc2008-08a-ghostly-ri...

from your link: "The magnetar itself is not visible in this image, as it has not been detected at infrared wavelengths (it has been seen in X-ray light)."

so what they are imaging is indirect effects of the magnetar, not the magnetar itself.

Re-read my post.

> That we've detected a radio source doesn't mean there's not something there in infrared as well, though.

The Spitzer image demonstrates there may be value to pointing something like JWST at it. Existence of a remnant tells us what probably made it, size of that remnant tells us how old it is, etc. (Lack of a remnant would be interesting, too.)

And when you eyes look at your computer screen they only see the light coming off it, not the actual screen.

yes. that's direct imaging. Your eyes are detecting photons emitted directly by the source at their emission frequency. Indirect imaging a monitor would be looking at nearby reflective objects that absorbed those photons and emitted different ones (fluorescence, phosphorescence, heated object...)

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