[nullc]

Producing an "image" of a black holes requires astronomical, ahem, resolution because they're so far away (thankfully). To achieve this kind of resolution you need an aperture of thousand of kilometers.

The EHT images are created using synthetic aperture techniques to create an effective aperture with a diameter of earth's orbit around the sun. But this is only currently possible at radio frequencies due to our ability to capture, store, and coherently combine the phase information. It's essentially SDR beam forming across space and time.

We can also study black holes though visible and IR observations through their effects of the things around them-- lensing from their mass, matter heated up by falling in. Here is an image I took of the relativistic speed matter jet believed to originate from black hole in M87: https://nt4tn.net/astro/#M87jet ... and Webb can do a lot better than I can with a camera lens in my back yard. :)

Aside, there is some controversy about the EHT black hole images. A recent paper claims to be able to reproduce the ring like images using the EHT's imaging process and a simulated point source-- raising the question of the entire image just being a processing artifact. https://telescoper.wordpress.com/2022/05/13/m87-ring-or-arte... Though it's not surprising to see concerns raised around cutting edge signal processing-- LIGO suffered from a bit of that, for example, but confidence there has been improved by a significant number of confirming observations (including optical confirmations of ligo events).

[pja]

> The EHT images are created using synthetic aperture techniques to create an effective aperture with a diameter of earth's orbit around the sun.

Small correction: The EHT is a synthetic aperture telescope the size of the Earth, not the size of the Earth’s orbit around the Sun.

Synthetic aperture telescopes need both amplitude & phase information from each observing station & have to combine the phase of simultaneous observations in order to create the final image. We can’t do this on the scale of the earth’s orbit, because we don’t have a radio telescope on the far side of the sun!

Maybe one day ...

[chrisweekly]

> "Here is an image I took of the relativistic speed matter jet believed to originate from black hole in M87: https://nt4tn.net/astro/#M87jet ... and Webb can do a lot better than I can with a camera lens in my back yard. :)"

You, sir, have just contributed a prime example of HN comments at their best. Your astrophotography is outstanding. Thank you for sharing! :)

[april_22]

Thank you!

Another question: are they already planning a successor to JWST? Is something better even possible? If it took more than 30 years, we should start sooner than later :)

[btilly]

The next better thing won't likely take 30 years.

https://caseyhandmer.wordpress.com/2021/10/28/starship-is-st... is correct. No NASA planning, including for space telescopes, shows any understanding of how much Starship changes the game. Instead of one, we can put up a network of telescopes. And try out crazy ideas.

Here is a concrete example. https://www.researchgate.net/publication/231032662_A_Cryogen... lays out how a 100 meter telescope could be erected on the Moon to study the early universe with several orders of magnitude better resolution than the JWST. The total weight of their design is around 8 tons. With traditional NASA technologies, transport of the material alone is over $30 billion and it had better work. With Starship, transportation is in the neighborhood of $10 million. Suppose that precision equipment added $40 million to the cost. Using Starship, for the cost of the JWST, we can put 200 missions of this complexity in space. Using a variety of different experimental ideas. And if only half of them worked, we'd still be 99 telescopes ahead of the JWST.

So where is Starship? It is on the pad, undergoing testing. They have a list of 75 environmental things to take care of before launch. Which means that they likely launch this month or next. At the planned construction cadence, even if the first 3 blow up, by Christmas it should be a proven technology.

[ceejayoz]

https://en.wikipedia.org/wiki/List_of_proposed_space_observa...

https://en.wikipedia.org/wiki/SAFIR is the closest to a proposed JWST successor; the others largely serve different purposes.