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I think there’s a couple new images. I’ll upload an updated one some time.

That said yes there is something about earths orbit. There’s a few month window that gives the best observation of this star. We time the observations to be roughly June- November most years.

As responded above, they were persistent diffraction errors in the primary mirror phasing. Think of it like those diffraction spikes from Hubble.

Indeed the video is almost entirely “fabricated” by motion smoothing and interpolation between images taken a year or two apart.

Good spot! It’s an error in the primary mirror segment phasing.

The observatory has to phase the mirror segments periodically, and it’s a bit of an art as well as a science. For a while, something was happening with their algorithm and procedure that was leaving those spots. Some of us (hi) did complain and it was fixed for the most part. It did come back a couple times though….

The slightly incorrect phasing produces those spots. It’s conceptually like a diffraction spike.

They probably have moons.

But I doubt they’re outshining other planets — other planets on the same orbit would be unstable, and most likely be ejected from the system very quickly. The system is about fifty million years old, so a good guess is that the orbits have been stable for about fifty million years.

The main reason, is why bother? We know there’s four planets, we know they orbit according to Keplers laws, we know how bright they are. The public outreach is reasonably well handled by this motion smoothed video. Better to use that telescope time to look for new planets instead!

Yeah each photo is one - five nights of work full time from 3-5 people.

Not stellar activity — a flare wouldn’t be visible on this scale of image. The main concerns are the observatory —- how aligned all the many dozens of optics are — and the earths atmosphere on the nights the target was observed.

In 2017 we captured five nights worth of images and averaged them. Some early years only had one night.

Around 2019 we also figured out some better observing strategies— all the later data is taken without a coronagraph. Turns out the coronagraph was hurting more than it helped, close in. Not to say coronagraphs aren’t useful, but some aspects of the observatory control software aren’t in place to get the benefits out of the coronagraph.

That’s right. We only have images take every year or so, so I did a motion interpolation between the images using Keplers laws. Diffraction close in gets pulled around by the interpolation.

Not to self-plug, but here's my video of the same four planets:

https://sefffal.github.io/images/orbital-animation.mp4

The creator of the GIF above used a data from a range of different telescopes and wavelengths, whereas I made this with using data only from same telescope (Keck), instrument, and wavelength (3.5 microns; near infrared).

This is maybe not the place, but we did some apples to apples comparisons between PyMC, Dynesty, and the Julia Turing.jl package.

A little to my surprise, despite being a Julia fan, Turing really outperformed both the Python solutions. I think JAX should be competitive in raw speed, so it might come down to the maturity of the samplers we used.

I visited the Large binocular telescope just a month or two ago. A very impressive facility, and one can only imagine the image quality if they were captured using both mirrors coherently.

That doesn’t seem to match what I understood from the article. At one point they say explicitly that it will enable brighter displays.

My understanding is that the AO system for GMT is going to pose quite a challenge. A big topic of ongoing research is dealing with “petaling” where the separate primary mirrors in phase due to the atmosphere.

For combining the projects, it does seem like that may be the only option funding wise, but it’s hard to imagine what the resulting observatory would look like. Maybe it would have to be a completely new design?

There’s a bit more to it than that. GMT is further along but its design has many compromises versus TMT. Also, a second ELT in the southern hemisphere is less useful than one in both Hemispheres. The situation for TMT on Maunakea is definitely tricky, but it’s also a better site than either of GMT’s or EELTs.

Worth mentioning that essentially all professional astronomers / astrophysicists consider this person a grifter. It’s amazing that he keeps getting so much press though, would love to learn his secret.

Yes exactly. Which means it's extremely, extremely low.

Even though the probably of a meteorite hitting somewhere is high, the probability of hitting somewhere in particular is tiny.

I’m using this from Julia and both the user and developer experience is great. It’s much more limited than publication style plotting libraries but the instant 60fps reactivity is amazing.

#3 spot at atmospheric pressure

Coming from matplotlib, I found Makie such a breath of fresh air. The API is just as (if not more) flexible but way more predictable. Their layout system in particular is amazing. I think it bundles it's own constraint engine? Congrats on the new website!

PS. Thanks to the Makie team for the shoutout to my corner plot package in the ecosystem section!

As has been pointed out elsewhere, this is the first image of our galaxy in something other than light (radio, infrared, x rays, gamma rays are all photons).

Would you mind explaining this further? Since sound is literally pressure waves, I don't understand how reducing sound can still leave "sound pressure".

This is not a “nature publication” in the common sense. It’s in their commentary section.

This is true but the poster above doesn’t mean Monte Carlo integration. Rather, testing those methods on simulations from generative models.

Small correction, no one will be able to pay for time on JWST. But if you put in a proposal for time and it's accepted, they will pay you. That's to make sure there is sufficient funds available to properly make use of the data you proposed for.

If you were to fly into these nebula in some kind of spaceship they wouldn't be any brighter than they appear in the night sky from Earth. They would just look way way bigger. The frustrating thing is that our eyes start to respond differently to colours when the light is really really faint. So we would probably perceive them as a grayish green haze. If the image was brightened artificiallythen we would see it as mostly red, with some browns and blues.

This is really impressive, and a great write up. I’ve been following the work on static compiling Julia to x86 libraries from the GPUCompiler.jl folks but I didn’t expect to see Julia working on an Arduino any time soon. With some kind of basic GC support (even if just using a bump allocator) it seems like a good fraction of the language could actually be available. Most tight loops hopefully don’t allocate so it would mostly just be necessary for creating initial arrays and mutable structs.

As others have mentioned, this is similar to how the event horizon telescope works today!

However, there’s no free lunch. By using arrays of telescopes instead of a single filled dish/mirror, they are missing a lot of information. Imagine a telescope the size of the earth, but you only use light from a few dozen spots on the surface and let the rest fall through. This is why they had to do all that complicated image reconstruction processing to create the image shown in the papers.

No, unfortunately those measurements have to be taken at the same time. That said, as the Earth rotates the distance between any two pairs of antennas changes which can be used to add additional information to the images (those new pairs of measurements again have to be taken simultaneously). From what I understand, this is less useful for looking at Sgr A* since the scene isn’t static and changes on a roughly 10 minute timescale.