How is the picture old? It was dropped this morning by 6 different agencies in unison, so no one would break the news ahead of the other. It's the FIRST picture of Sagittarius A* EVER
You don't have to worry. No threads have ever disappeared here. Ever. In all of known history. Since the start of time itself.
Depends on the Astronomer... Dr Amy Mainzer - JPL Dr Becky Smethurst - Oxford Sadly a google search brings up very more "Hot Astronomers"....
Actually opposite. Solar stuff is narrow band so looks B&W. Then you can do cleanup which really brings it up.
Taken the same day but processed differently....kind of like the photographer that can make you look faster..
Huh, I woulda thought it would be like looking up into the depths with the naked eye when there was zero ambient lighting, but looking a lot deeper. So, no real depth perception through the scope?
This is copypasta from Reddit, but some great insight as to WHY the image in the first post is so important/groudbreaking: What is this picture of? Sagittarius A* (Sgr A* for short) is the supermassive black hole (SMBH) at the center of our Milky Way, and weighs in at a whopping 4 million times the mass of the sun and is ~27,000 light years away from Earth (ie, it took light, the fastest thing there is, 27,000 light years to get here, and the light in this photo released today was emitted when our ancestors were in the Stone Age). We know it is a SMBH because it's incredibly well studied- in fact, you can literally watch a movie of the stars orbiting it, and this won the teams studying it the 2020 Nobel Prize in Physics. So we knew Sag A* existed by studying the stars orbiting it (and even how much mass it had thanks to those orbits), but no telescope had enough resolution to see the black hole itself... until now! Note, you cannot see Sag A* in our own night sky because of all the dust between us and it. However, other wavelengths like infrared and radio can go straight through that dust even if visible light can't. (Btw, it is called Sagittarius A* because in the early days of radio astronomy the brightest radio source in a constellation was called A, and at some point the * was added to denote a particularly radio bright part of Sagittarius A. We're so creative with names in astro...) Didn't we already have a picture of a black hole? Why is this one such a big deal? We do! That black hole is M87*, which is 7 billion times the mass of the sun (so over a thousand times bigger than Sag A*) and is located 53 million light years from Earth. It might sound strange that we saw this black hole first, but there were a few reasons for this that boil down to "it's way harder to get a good measurement of Sag A* than M87*." First of all, it turns out there is a lot more noise towards the center of our galaxy than there is in the line of sight to a random one like M87- lots more stuff like pulsars and magnetars and dust if you look towards the center of the Milky Way! Second, it turns out Sag A* is far more variable on shorter time scales than M87*- random stray dust falls onto Sag A* quite regularly, which complicates things. As such, if you compare the old black hole pic vs this one, you'll see a lot more artifacts at the edge of this one's ring. It's just tough to get a perfectly clear image in radio astronomy. I thought light can't escape a black hole/ things get sucked in! How can we get a picture of one? Technically this picture is not of the black hole, but from a region surrounding it called the event horizon. This is the boundary that if light crosses when going towards the black hole, it can no longer escape. However, if a photon of light is just at the right trajectory by the event horizon, gravitational lensing from the massive black hole itself will cause those photons to bend around the event horizon! As such, the photons never cross this important threshold, and are what we see in the image in this "ring." Second, it's important to note that black holes don't "suck in" anything, any more than our sun is actively sucking in the planets orbiting it. Put it this way, if our sun immediately became a black hole this very second, it would shrink to the size of just ~3 km (~2 miles), but nothing would change about the Earth's orbit! Black holes have a bigger gravitational pull just because they are literally so massive, so I don't recommend getting close to one, but my point is it's not like a vacuum cleaner sucking everything up around it. (see the video of the stars orbiting Sag A* for proof). How was this picture taken? First of all, it is important to note this is not a picture in visible light, but rather one made of radio waves. As such you are adding together the intensity from several individual radio telescopes and showing the intensity of light in 3D space and assigning a color to each intensity level. (I do this for my own research, with a much smaller radio telescope network.) What makes this image particularly unique is it was made by a very special network of radio telescopes literally all around the world called the Event Horizon Telescope (EHT)! The EHT observes for a few days a year at 230–450 GHz simultaneously on telescopes ranging from Chile to Hawaii to France to the South Pole, then ships the data to MIT and the Max-Planck Institute in Germany for processing. (Yes, literally on disks, the data volume is too high to do via Internet... which means the South Pole data can be quite delayed compared to the other telescopes!) If it's not clear, co-adding data like this is insanely hard to do- I use telescopes like the VLA for my research, and that already gets filled with challenges in things like proper calibration- but if you manage to pull it off, it effectively gives you a telescope the size of the Earth! To be completely clear, the EHT team is getting a very well-deserved Nobel Prize someday (or at least three leaders for it because that's the maximum that can get the prize- it really ought to be updated, but that's another rant for another day). The only question is how soon it happens! Also, the Event Horizon Telescope folks are giving an AMA on r/askscience at 1:30pm-3:30pm (EDT) today! link Definitely go over and ask them some questions I didn't cover here! There is also a live public Q&A at 10:30am here, and another livestreamed public Q&A panel at 3pm EDT with some great colleagues from my institute- check it out! This is so cool- what's next?! Well, I have some good news and some bad news. The bad news is we are not going to get a photo of another supermassive black hole for the foreseeable future, because M87* and Sag A* are the only two out there that are sufficiently large in angular resolution in the sky that you can resolve them from Earth (Sag A* because it's so close, M87* because it's a thousand times bigger than a Sag A* type SMBH, so you can resolve it in the sky even though it's millions of light years away). You would need radio telescopes in space to increase the baselines to longer distance to resolve, say, the one at the center of the Andromeda Galaxy, and while I appreciate the optimism of Redditors insisting to me otherwise there are currently no plans to build radio telescopes in space in the coming decade or two at least. However, I said there was good news! First of all, the EHT can still get better resolution on a lot of stuff than any other telescope can and that's very valuable- for example, here is an image of a very radio bright SMBH, called Centaurus A, which shows better detail at the launch point of the jet than anything we've seen before. Second, we are going to be seeing a lot in coming years in terms of variability in both M87* and Sag A*! Black holes are not static creatures that never change, and over the years the picture of what one looks like will change over months and years. Right now, plans are underway to construct the next generation Event Horizon Telescope (ngEHT), which will build new telescopes just for EHT work to get even better resolution. I recently saw a talk by Shep Doeleman, the founding director of EHT, and he showed a simulation video of what it'll be like- basically you'll get snapshots of these black holes every few weeks/months, and be able to watch their evolution like a YouTube video to then run tests on things like general relativity. That is going to be fantastic and I can't wait to see it! TL;DR- we now have a picture of the black hole at the center of the Milky Way. Black holes are awesome!!! Edit: Because people are asking, the James Webb Space Telescope (JWST) will not be able to do anything to this type of science either to add to it or observe the black hole itself. First, it is not at the right wavelength of light, and second, it has nowhere near enough resolution to pull this off!
Oh there is but the contrast sucks. Also that is Hydrogen Alpha band while I also have a Calcium K filter which does change the layer you are mainly perceiving. Fascinating stuff but I have not been able to exercise the equipment I have due to moving and chaos in life prior to that.
https://www.reddit.com/r/science/co.../?utm_source=share&utm_medium=web2x&context=3 That's the link to the direct comment in the original thread.
My 10 year old genius son wants to start an astronomy club so he cam make up club T-shirts that say "We know more aboit Uranus than you do"
I know nothing about space etc. I did however have the pleasure of knowing Jeffrey and Margaret Burbidge. Margaret was such a sweet and gentle wee woman. https://www.nytimes.com/2020/04/06/science/space/e-margaret-burbidge-dead.html
You'll want an Infinite Improbability Drive for that. It'll take ya just a moment to get wherever you're going. Bit of trivia, Astronomy Domine might literally translate to Star Lord.
