First ever image of SUPER-MASSIVE black hole –how big is it?

so this guy comes into the lab really excited they've just measured the first image of a black hole and my immediate response was let's start with the obvious we can't resolve stars local stars as anything other than point sources even with our most powerful telescopes like Hubble black holes are damn sight smaller than stars seriously if we were to turn the Sun into a black hole the event horizon would fit within most cities the need tell us big but it's not even in our galaxy at which point I say now I know you're really talking crap although cool stars are just a few light-years away and we can't resolve those as anything than point sources galaxies are millions to hundreds of millions of light years away you definitely won't be able to resolve stars there as anything other than point sources and ya can't make an image off one point then he mentioned something interesting that it was in the galaxy called m87 which point I kind of quietly chuckled I've actually seen m87 this galaxy with the naked eye well there and through a telescope and even with a good telescope under a dark sky you're not really gonna see anything other than an oval smudge of light however m87 is famous for one thing it's got this large jet coming out out the middle of it which has been thought to be due to a massive black hole but do actually see that jet you need a really long exposure taken with a really impressive telescope see m87 is close in intergalactic terms but still a very very long way way to the point where these is the best resolution image the Hubble got of it and you can barely see any stars there well other than the ones in the foreground the ones in our own galaxy you all you get is this general featureless glow which is caused by billions of distant stars so what the hell is going on here what did these boys image I mean they didn't look like they're making it up to me well you gotta understand what it is that telescopes actually do and to a degree how they do it you see what telescopes do is they allow you to see faint objects and small objects the ability to see small objects is called a resolution and it depends on the diameter of your mirror or lens now if you get a bright but small object like a planet then you don't really need a big telescope to get lots of photons you need it for the resolution now in terms of resolution the optical limit is basically dependent on the diameter the baseline of the mirror and it turns out that wouldn't you get up to about 12 inches or 30 centimeters it really doesn't help you to get a bigger telescope than that for resolution because you are always limited by the atmosphere I mean sure a bigger telescope will help you get more photons and see fainter objects but it won't help you see smaller objects but what if we were on the moon what if you weren't limited by the atmosphere well sure then there the bigger the baseline of the telescope the better the resolution but turns out that because of the way the optics work yet don't need the whole mirror there just a few part of it will work fine in mostly keeping the resolution now in a telescope like this you can just put your eye to the eyepiece and it would work fine because you're keeping all the way front data but building a telescope like this is really impractical so there's this trick that rather than building one giant telescope you get lots of little telescopes and then because this turns out to be important for the optics you've got to record the same wave fronts and seeing is that light arrives the telescope's at different times you've got to hook up delays between when they actually record their data and from that boom it turns out you can get the resolution of the large effective diameter telescope now that might sound like merrily complicated and to a degree it is but it's a damn sight easier than building one giant telescope so a typical radio interferometer looks like this interferometer is just one of these devices that uses this partial effective mirror trick to get better resolution but they're not limited to single sight machines like this you can actually spread your radio telescopes all over the surface of the planet and have an effective radio telescope diameter of the entire planet now for a variety of reasons it turns out this is much easier to do with long wavelengths of light things like microwaves and radio waves and much harder to do as the wavelength of like it's shorter the practical upshot is the world's biggest visible interferometers have a baseline of about 1/3 of a kilometer or so now it turns out for their baseline like that you can just about get an image of a star as a non point source so how are ya gonna get an image of a black hole in a distant galaxy especially when this was the best that Hubble can do well you need a really big interferometer one of these ones that worked on a planet-wide scale and because of that you need to work at a much longer wavelength so these guys were working at a wavelength of about a millimeter so that's the visible spectrum there it's about a micron that's a thousandth of a millimeter and now we can zoom out to a millimeter which is about the thickness of a dime and just for reference here the microwaves that you use to cook with in the microwave oven have a wavelength of about 12 centimeters that's about 12 Dimes put end-to-end and obviously once you get an effective baseline and effective diameter for your telescope the size of the earth and how we talking angular resolution cool so how angular ly big is this black hole well let's just take the moon as a benchmark here if you get a circle and chop it up into 360 portions each one of those is a degree the moon and the Sun both appear in the sky it's about half degree in size now if you take one of those degrees and chop it up into 60 each one of those is an arc minute and Jupiter from the earth appears is about one arc minute in size so if I get a camcorder and zoom right in on the moon and right in on the Jovian system the Jupiter system what I find is Jupiter and all of its moons are about the same angular size as the moon so Jupiter's diameter is about an arc minute comparable to a large crater on the moon and just so we've got this all in perspective the entire m87 galaxy and not just the bright core the whole thing is about seven arc minutes in size in each arc minute you'll be happy to know it's cut up into 60 arc seconds an arc second is pretty much the best resolution that you can hope to get from a terrestrial based telescope like this one that I was talking about earlier it's also about the angular size of the four big moons of Jupiter now those moons are about the same size as our Moon but obviously a long way away so that's one arc second in size or when you could resolve about 60 features across the disk of Jupiter with a good telescope on a good night so how big is this black hole in comparison angularly it's about a million times smaller than an arc second it's not measured in arc seconds but millionths of an arc second micro arc seconds and just the reference here Hubble's best resolution was about a twentieth of an arc second so this is still about a million times smaller than Hubble could resolve that being said these is still not enough to resolve a black hole because in reality you can never see a black hole they're about the size of an atomic nuclei that are a singularity so if you were to magnify the air that you're breathing by a factor of about a billion you would see something like this kinda I think the details were explained in life in the ball pit yeah I think that's air you're breathing so you get out of the atoms and then you have to magnify those also by a factor of a million and you'll get down to the size of the atomic nuclei that's about the size of a black hole you can never see them however black holes have this border around them from which the gravity is so strong that the light can't escape it's called the event horizon is essentially the point of no return now event horizons for black holes of stellar type masses and typically tinier few kilometers that sort of thing however the black hole in m87 is just a tiny bit bigger now technically it's exactly the same size of course they're all singularities but it's mass is much bigger it weighs as much as about a billion suns packed into this thing which is really quite impressive it's about 1% of the entire mass of the galaxy it also means that the event horizon it's quite big and when I say quite big no not not just a few kilometers no no that's that's that's nothing not bigger than the earth that's tiny or bigger than the Sun also ain't and significant not bigger than the Earth Sun orbit again that's nothing if you were to zoom out search then you could see the entire solar system the event right under this black hole is about four times the diameter of our entire solar system now this video is gonna be about 10 minutes inland that sort of thing so in that time light that was leaving the Sun will have just about arrived at Earth in about four hours the light from the Sun reaches the edge of our solar system so it takes about eight hours for light to cross our entire solar system or it would take about a day and a half for light traveling the equal distance from event horizon to event horizon across this black hole but that's still not what you're looking at here you see the inner most stable orbit you can get around a black hole is about three times the diameter of the black hole of the event horizon and that's the thing that you're actually looking at here that's what emitting the light because the stuffing all bit there he's moving almost at the speed of light so it's really hot well it's but this is a human perspective the most distant man-made object is Voyager 1 and it's about 20 billion kilometers away so if we were at the center Voyager 1 the most distant man-made object would have only just reached the event horizon there that's how big this object is so not only would light take over a week to go just from one side of this structure the other assuming that wasn't a black hole in the middle of course it then takes another 55 million years to reach us that is when these photons were leaving the black hole when they first started their journey the dinosaurs had only just died out but it's the massive size of this thing which is why you have a chance of seeing it well that plus the thing that we're not looking in visible light but light with a wavelength of about a millimeter these are not real colors and we're using an interferometer with a baseline the size of the planet and so if that inspired you to look to the heavens and actually see some of this yourself with the naked eye but the night is dark and full of Wonders the movement the planets are always fantastic even from small telescopes from cities and in a dark sky the sky is full of galaxies and nebulae and some beautiful binary stars so if you want to see some of those for yourself I'll leave a link at the end of this video about which telescope would be right for you because believe it or not bigger isn't always better trust me this thing weighs a ton sure it can do some fairly impressive stuff like a time-lapse of an exploding star a super over all a time-lapse of an entire rotation of Jupiter from the spinning surface of the earth or at least some Amazon affiliate links to telescopes below that I would recommend for different users in different conditions so if you enjoyed that give this video a thumbs up and hit the like and subscribe button and if you want more behind-the-scenes footage or just general blogs you can see my other channel with voice of thunder and if you really enjoyed this and one support this channel directly you can do it through patreon and I'll leave the links below [Music]

Channel: Thunderf00t

Views: 339,943

Rating: 4.7952194 out of 5

Keywords: black hole, black, hole, star, astronomy, m87, interferometer, telescope, which, to, buy, thunderf00t, jupiter, sun, moon, stars, saturn, space, night, solar, new, discovery, amazing

Id: dbgBlQVfpPk

Length: 14min 6sec (846 seconds)

Published: Thu Apr 11 2019