Discoveries using the telescopes on Mauna Kea

[HereOnThePrimalEdge]

The Event Horizen Telescope consists of not a single observatory, but multiple radio telescopes around the world, operating concurrently, in an attempt to emulate a virtual telescope the size of the Earth, which will take the first ever photograph of a black hole.

They spent a couple weeks on Mauna Kea, installing and testing borrowed equipment and waiting on the weather. On clear nights they’d stay up from well before dusk until after dawn, when they’d pack hard drives filled with billions of numbers representing noise and cosmic signal into foam crates. They’d draw straws to decide who had to drive the crates down to Hilo and FedEx them back to Haystack for correlation. At the end of the run, they dismantled their equipment and shipped it back East.

https://www.nytimes.com/2018/10/04/magazine/how-do-you-take-a-picture-of-a-black-hole-with-a-telescope-as-big-as-the-earth.html?smprod=nytcore-ipad&smid=nytcore-ipad-share

[TomK]

Oh, for the days when astronomers were real astronomers!

[HereOnThePrimalEdge]

the days when astronomers were real astronomers!

Yes, bunch of young whippersnappers these days peering up at the sky, and on their screens. Next thing you know, virtual astronomers will just sit in their holodecks all night, AND all day looking at simulations!


We had some discussion on Punaweb in the past about adaptive optics, as it's used by the military and in astronomy. Neil DeGrasse Tyson in a recent interview discussed how the military uses adaptive optics, then the manner in which it was incorporated into modern astronomy. It's not a military weapon as some have stated, but a defensive measure for tracking incoming missiles. It's best to read (or listen to) the entire section of his interview about adaptive optics, but in part:

TYSON: And - if there's a dot of light high up in the atmosphere, it could be the afterburner of a missile headed our way. The light - ... passes through many layers of air, layers that are not all at the same temperature, layers that are not all stable... And by the time that bit of light makes it through, the position of the thing in the sky does not precisely correspond with where you think it is from where the light came from.

The military wants to hit its target and doesn't want to miss, so they invented something called adaptive optics, and it is a way of tracking what the air is doing and then compensating for it at your telescope that's doing the measuring. It completely undoes the thing that made it bend and wiggle and jiggle so that when you aim for your target, you hit it. We didn't know anything about this in astrophysics until one day at an astrophysics conference, someone who is related to that study and that - those discoveries gave a paper on it. And we said, yeah, we're taking it, OK? And it had finally become declassified.
https://www.npr.org/2018/09/17/648693243...ce-and-war

[kander]

quote:

---

Originally posted by TomK

[b]"The Goblin":

http://www.ifa.hawaii.edu/info/press-rel...2015TG387/

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what about the many other smaller objects in the time compare images that show movement? are they known objects and named because some of them appear to be much farther out.

[TomK]

HOTPE - I believe adaptive optics was actually first thought of by astronomers back in the 1950s but the technology wasn't available to develop it. The military then developed the idea as they had an awful lot more money, but essentially it was always an astronomical idea. Once the military had developed it then it became available to others (not just astronomy, it's used in other fields as well).

kander - I don't think there are any other moving objects in the time-lapse image other than one possibly faint object in the bottom right of the image. All the other objects in the field are background stars. They may appear to move slightly because the images were almost certainly not taken at the exact same telescope position and in the same conditions - plus there may be one or two variable stars in the field.

The faint objects in the field are not smaller, just less bright. All the objects are point sources but the atmosphere mucks that up a bit, and you can have very bright stars that are very distant or very faint stars that are much nearer, so you can't use their brightness as a guide to what or where they are.

[kander]

tomk,
I understand what your saying and I understand there could be some parallax in the photos, but there are at least a couple objects that clearly move. one is just above the star center right of newly discovered planetoid. Perhaps the next image taken from the area will either confirm other objects or not.
Just name if after me if its real
Thanks for the astro updates!

[dan d]

I was lucky enough to take a tour of the vlba a few years back when this idea just started,with the whacos,west hawaii astronomy club.and the took us into there farady cage
That cotrolled allof the seperate radio dishes,and correlated the data. They said when they were done linking all of the radio teles in the world they woulld be able to see rite up to the edge of the event horizon of the supermassive black hole at our galaxies center.

Wow I thought the altitude had gotten to his brain,but what an accomplishment!!!!!
We went to 3 telescopes that day and that was the last one. Talk about no oxy after 5 hours up there goin up and down stairs. The vlba main control building had o2 injected into the air and we were high on 20 percent o2 and didnt want to leave LOL.
Was fun thanks to Andrew Cooper our whaco president and keck engineer.
Aloha

Dan D
HPP

[TomK]

Kander - I think I see the object you're talking about - extremely faint and just above the Goblin. The movement is extremely small so think future images will show if it's really moving or not. If it really is moving, I'll be sure to contact the IAU and recommend it be called Kander!

[TomK]

Dan - thanks for that. The whole point of the VLBA is to simulate a telescope that has the diameter of the earth and one of their telescopes is on Mauna Kea, although well below the summit. It's easier to do this with radio telescopes as the wavelength of radio waves is so large so as long as you have precise time measurements you can just send all the data to one site and it will use the concept of interferometry to produce an image in unprecedented detail. Unfortunately, it's much harder to do this at optical or infrared wavelengths although the two Kecks on MK have managed to successfully produce optical interferometry results.

Unfortunately, I believe they have given up on that project for the time being as it's just so hard to do. Even tiny changes in temperature affect the results to the point that trying to correct for them is too expensive.

[HereOnThePrimalEdge]

A book about the VLBA will be released next week:

Einstein’s Shadow
By Seth Fletcher

I couldn’t find a table of contents to find out how much may follow their team on Mauna Kea, but hopefully thereks at least a chapter, or two. Here’s an except from a review:
Telescope upgrades and malfunctions get detailed explanations in the book. Astronomy buffs will probably enjoy those passages, but others may find them a bit dull. That feeling, however, may put readers in astronomers’ shoes — science sometimes can be slow.

We won’t know what EHT saw until the team releases its results. According to Doeleman, that should happen early next year. If EHT eventually unveils a black hole portrait, the dirty and dull work that was necessary to get the project off the ground will likely be glossed over in media coverage. Einstein’s Shadow reveals parts of the scientific process that, like the Milky Way’s gigantic black hole, are usually left in the dark.
https://www.sciencenews.org/article/eins...le-picture

"No one is such a LIAR as the indignant man." Beyond Good & Evil, 1886 - Friedrich Nietzsche