The most anticipated Astronomy Event of my life from mm waves: - Page 1
Forum section: electronics / general

author: Beamin
author_rank: Super Contributor
timestamp: June 04, 2018, 05:14:53 pm
content: They (scientists) are using Millimeter waves to resolve what a black hole in Sagittarius A 25,000ly away *actually looks like using telescopes from all over the planet. They said something about the size of the planet and mm waves are the perfect resolution by some random fluke of nature to do this much like how the moon and sun are perfect sizes to give us eclipses but they didn't elaborate on why. They have the data in after waiting six months for data from the south pole to be flown in.For me this is the most exciting event because ever since I was a kid I was obsessed with black holes and what they actually looked like. From the simulation, the black disc with gravitational lensed galaxies around it isn't what they look like, as they are feeding off something most of the time. It looks more like a candle with a marble in it that is spinning. I'm still trying to imagine a 3D hole and if you could walk into and out of it. How you could walk in would be easy, but to get out you would have to walk around a corner like a 2D hole but to do that in 3D you have to make a 90' turn somehow so it would be a 360' turn. Still boggles the mind to have a hole in space in 3D.https://eventhorizontelescope.org/Trying to find more info on the radio/mm wave array and the strange place between RF and light.

author: eecook
author_rank: Regular Contributor
timestamp: June 05, 2018, 08:39:42 pm
content: I am actually following the events myself. Can't wait to see the final render!

author: Beamin
author_rank: Super Contributor
timestamp: June 07, 2018, 04:16:19 am
content: Quote from: eecook on June 05, 2018, 08:39:42 pmIt still boggles my mind how people can say the earth is flat or 5000 years old when we can actually see this stuff or how they will use the internet to tell people this, when that relies on the speed of light being finite to work or bounce of satellites or microwave links that are aimed with the curvature of the earth in mind.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 07, 2018, 05:56:10 am
content: Between that, and the gravitational wave observatories now finally online ("now" being relative to the long history between knowing of them, and finally detecting them), and the various planned space telescopes and interplanetary missions, and operational or already-completed missions like Cassini and New Horizons and Curiosity and more... it's a pretty cool time to be alive.Tim

author: Beamin
author_rank: Super Contributor
timestamp: April 10, 2019, 12:54:01 pm
content: 7 minutes until they post the pictures!!!!

author: Beamin
author_rank: Super Contributor
timestamp: April 10, 2019, 12:55:09 pm
content: https://youtu.be/lnJi0Jy692wForgot link too excited!!

author: Beamin
author_rank: Super Contributor
timestamp: April 10, 2019, 01:55:54 pm
content: here it is a yellow orange smudge. Meh.https://news.harvard.edu/gazette/story/2019/04/harvard-scientists-lead-team-revealing-black-hole/

author: Beamin
author_rank: Super Contributor
timestamp: April 10, 2019, 03:07:41 pm
content: This is the best video to explain what you are seeing:https://youtu.be/zUyH3XhpLToAlso this is the M87 black hole not sag a star like they said or I thought they said they were imaging.Its event horizon is the size of Neptune's orbit. Crazy.

author: orion242
author_rank: Unknown
timestamp: April 10, 2019, 11:00:36 pm
content: All the hype this morning and then I saw the results....blurry nothing burger imo.

author: Halcyon
author_rank: Unknown
timestamp: April 10, 2019, 11:08:21 pm
content: Quote from: Beamin on June 07, 2018, 04:16:19 amI know there are literally thousands of videos out there debunking flat-earthers, but this one is particularly worth a watch (if for nothing else but a laugh). This guy responds to a bunch of flat-earthers (and you hear their responses). It just goes to show how insane these people are:

author: hamster_nz
author_rank: Super Contributor
timestamp: April 11, 2019, 06:29:17 am
content: I assume the mm wavelength is important, as the angular resolution is a function.of the wavelength over the up to ~13,000 km baseline between observatories.When you think about all the magic needed, such as to take the ionospheric conditions into account, it is mind-boggling.

author: RobBarter
author_rank: Regular Contributor
timestamp: April 11, 2019, 12:52:35 pm
content: mm wavelength definitely improves resolution but it brings heaps of problems with the VLBI aspects. Been looking at what it would take for an amateur to do VLBI at 22cm and the sampling frequency has to be spot on. Maybe 10% of the wavelength for the whole of the viewing period with no jitter.

author: Mechatrommer
author_rank: Super Contributor
timestamp: April 11, 2019, 03:43:48 pm
content: what are we seeing here? right a black hole. it was black before, and it is still black today, or the lensed light around it no?. fascinating the most a wonderful time to live, i've heard that since the day of aristotle. next step is using um, nm, pm wavelength to get closer and closer to see that it is still black, what a wonderfull age that will be when it comes.

author: apis
author_rank: Super Contributor
timestamp: April 11, 2019, 09:42:38 pm
content: Now they just need to put these things in space. Imagine hundreds of gravitational wave observatories in orbit around the sun with detector arms that are not 4 km long but 4 million km. Or hundreds of very very large radio telescopes that are not 13000 km apart, but 300 million km apart (or more). We would be able to see planets in other solar systems.

author: chris_leyson
author_rank: Super Contributor
timestamp: April 11, 2019, 10:36:45 pm
content: It's an amazing achievement getting an image of what a black hole might look like. It's taken a lot of hard work from many scientists to get this far but without the work of Dr Katie Bouman at MIT it would never have happened. Here's a recent TED talk from Katie Bourman.https://youtu.be/BIvezCVcsYs

author: BillB
author_rank: Unknown
timestamp: April 11, 2019, 11:06:00 pm
content: It's a shame the perceived "low-quality" of the image diminishes the profound importance of this event in the eyes of the general public (I blame Interstellar). To essentially have evidence that validates our model of black holes and further demonstrates the predictions of General Relativity is amazing, indeed.I can't wait to see Sagittarius A*!

author: chris_leyson
author_rank: Super Contributor
timestamp: April 11, 2019, 11:57:21 pm
content: QuoteTo be honest I would say it was a damn good high quality image for eight radio telescopes located on a small blue blobShame that pioneers like Karl Jansky and Bernard Lovell couldn't see this. Interesting times indeed. Edit: I think the general public are too busy looking at their smart phones rather than the world around them let alone the sky above them.

author: orion242
author_rank: Unknown
timestamp: April 12, 2019, 12:31:58 am
content: Nothing burger...

author: electromotive
author_rank: Regular Contributor
timestamp: April 12, 2019, 12:33:50 am
content: The young woman that worked to create the algorithm to make this all come together most certainly deserves high accolades, and at minimum, the attention of the Nobel. Having looked at the mathematics involved (and having a background in higher level mathematics), it's no simple task to process 4D-in-3D information into 3D, without it coming out a mess. It's a weird sort of recursion going on to make it all work properly, or at least well enough to image it *reasonably* accurately.To be honest, I'm astounded it happened in our lifetimes, and I'm glad I got to see it.

author: orion242
author_rank: Unknown
timestamp: April 12, 2019, 12:50:11 am
content: Its impressive it can be done. Just because it can be done, doesn't mean there is a solid reason to do it.

author: Mechatrommer
author_rank: Super Contributor
timestamp: April 12, 2019, 01:36:18 am
content: that Katie Bouman video is reasonable since she used most words like assume, infinite number of possibilities, the "algorithm", hope and "we cant see it yet". at least she knows better what a reality looks like.. If you are able to pass through the regions of theheavens(sorry its a tabbo word, change with "sky") and the earth, then pass through; you cannot pass through but with authority ("Quotation" 55:33) they asked for it and they got (are given to) it, a little at a time

author: hamster_nz
author_rank: Super Contributor
timestamp: April 12, 2019, 03:26:49 am
content: Ask people..."How far away do you think that Black Hole is, you know, the one we got that glimpse of this week?"The answer is just so mindbogglingly huge that no matter what people say you just say "nah, much further".(500 000 000 000 000 000 000 000 000 000 km)

author: hamster_nz
author_rank: Super Contributor
timestamp: April 12, 2019, 04:45:39 am
content: Well worth the watch - from about 2 years ago

author: soldar
author_rank: Super Contributor
timestamp: April 12, 2019, 06:53:47 am
content: Big publicity stunt for a whole lot of nothing.False color, computer generated "artist's impression" of what it might look like if it looked like that. Meh.Don't get me wrong. This might well be an important milestone for the scientific community and the advancement of science but the way the release of the "photo" was done is just a publicity stunt with the object of gaining exposure. Just like the presentation of a new commercial product. They make it into a big deal just to attract attention.

author: magic
author_rank: Super Contributor
timestamp: April 12, 2019, 09:33:00 am
content: All radio imaging is false color, and for good reasonIt's not "artist's impression" either, radio images are produced by scanning over the target with a directional antenna. It's a legitimate image.They used VLBI to improve resolution, fair enough, the basic technique has been in use for decades.Now, they claim some novel DSP techniques to get the resolution down so that could be fishy. But per the Harvard article linked earlier, the processing has been independently performed by four teams using four different techniques and there are big name universities standing behind the effort so I would presume it's legit.The TED talk supposedly does not describe any of the techniques used this time.

author: soldar
author_rank: Super Contributor
timestamp: April 12, 2019, 04:21:07 pm
content: Don't get me wrong. I am not saying it is not legit.I am just saying that they have made a big show which is misleading. The discovery may be very significant for the scientific community who have the background to understand and interpret but they made a big show to present it to the general public and it is misleading because the general public has no idea of the meaning of any of all this. Most people on the street will think that is what a black hole actually looks like.The purpose of this presentation and all the fanfare surrounding it is to gain exposure for themselves and their work and garner support and funding.Pretty much like the launch of any Apple product: carefully anticipated and choreographed so as to get max exposure in the news.

author: magic
author_rank: Super Contributor
timestamp: April 12, 2019, 04:37:46 pm
content: Quote from: soldar on April 12, 2019, 04:21:07 pmPoint taken, you may be right. I'm a bit out of touch with "most people on the street" to be honestIf they cared about not being misleading to laypeople they probably could have made more effort to stress that it's radio not visible light and the accretion disk rather than the hole itself. But we live in age of clickbait, so "an image of the invisible" fits the fashion, I guess. Yeah, you're right, I think I remember I used to hate it too.

author: iMo
author_rank: Super Contributor
timestamp: April 12, 2019, 04:51:39 pm
content: On the other hand it is great we've got the nice picture this week because the black holes evaporate over time.. Soon or later there will be none black holes..

author: Beamin
author_rank: Super Contributor
timestamp: April 28, 2019, 01:19:12 am
content: Quote from: Mechatrommer on April 12, 2019, 01:36:18 amWhat the hell are you talking about? That's not sarcasm. Are you saying it's a fake picture or the science behind it is flawed? Maybe it's because I just watched that flat earth video is why I see this post like that. The flat earth people make the most absurd claims and have no idea how to even for a good debate. Even if you are dead wrong but you understand how to debate you can make it seem like you are right and the other side is wrong. I don't know who the guy in the video was arguing against but it was weak at best. Shows how scientifically ignorant people are in this country or how the internet with vast amounts of free instant information can be ignored and rather found the just plain wrong. Imagine if people like Newton or the ancient Greek thinkers had access to the internet all the ideas they would have come up with?As to the "false color image" it's mm waves so there is no color and a B&W image isn't sexy or futuristic although probably more realistic. Plus you can't see it close up even if you were 100 AU away as the light's just bent in. They should have explained it more like in that veritasium video to blow peoples minds if they knew what they were actually looking at. And yes, it's also a PR stunt, but wouldn't you want funding for this sort of thing? With all the absurd things we waste money on this is real cutting edge science that advances our understanding of the universe and brings us one step closer to a star trek civilization... or the great filter/singularity/creating a strangelet as we pursue technology and accidentally destroy ourselves. The fact we saw something that big(small) that far away, opens the door to studying all kinds of things outside our galaxy which was impossible just a few years ago. I'll take a nothing burger, hold the event horizon please. Also who knew it would be orange and not glowing green since it's full of radioactive stuff!!!

author: Kyl8145
author_rank: Contributor
timestamp: April 28, 2019, 01:49:02 am
content: Quote from: soldar on April 12, 2019, 04:21:07 pmBut that is what a black hole actually looks like. In fact, from what I have read of one physicist who does simulations regarding how a black hole would look like if you could just look at it, it was almost a bit of a let-down because the simulations, based on general relativity and all that, are apparently so spot-on. I.E., the image didn't show them anything they didn't already know as far as knowledge of current physics, just confirmed it. They didn't go, "Oh wow, now this is something new, we didn't know that THIS is how black holes actually look," instead it was, "Yeah, that's EXACTLY how the simulations we run say it should look." The team that produced the image consisted of multiple separate teams that utilized different methods so that there would be no confirmation bias, and they all got the same result. Then they tried to find ways to "break" the image produced, if-you-will, and couldn't do it.A black hole looks like a sphere of blackness, with the sphere's shape warped somewhat due to the force of gravity and how it bends the light as it travels. That is exactly how this black hole came out. Normally they are very hard to see because space is generally dark where they are, but this one was of a black hole earlier in its life with a lot of light around it, thus allowing them to be able to image it.

author: Beamin
author_rank: Super Contributor
timestamp: May 01, 2019, 11:54:09 pm
content: Quote from: Kyl8145 on April 28, 2019, 01:49:02 amI want to know what it would look like if it was in front of an opaque object like a glowing gas/dust cloud. Would it do the strange Einstein rings and what not? Our brains are not good at seeing photons that don't travel in a straight line we actually infer that that's where the photon came from. Our brain is an interferometer that assumes the photon came from where we saw it. You can't see the side of light and once you see it you have interacted with and changed the particle. .

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 02, 2019, 06:49:56 am
content: Quote from: magic on April 12, 2019, 04:37:46 pmyou have just made contact with one... this thread originator