What You'd See When Falling Into or Orbiting Black Holes - VR/360

hello it's scott manley here and today we have an immersive 360 video to talk about gravitational lensing so you should be able to move the camera around but right in front of us right now there should be a black hole and if you saw the black hole there you saw a ring of light around it that is an Einstein ring now the gravity field off the black hole is bending the light around the edges and at exactly the right point at that ring you're seeing all the light is being bent around and it's focusing on a single point directly behind the black hole so if a star is there you will see a bright ring now inside there you'll also notice that this motion of the stars is kind of messed up in Reverse that's because inside that ring in some places you're getting a mirroring effect so the stars appear to be moving in the opposite direction we're currently rotating in a vertical orbit but if you look inside the Einstein ring the stars on the left and the right are actually going in the opposite directions from the stars visible on the other side at the top in the bottom they're still moving in the correct direction but their motions are still distorted okay for the next trick we're gonna have to drop you into a black hole so we're gonna descend feet first if you look down it's there just waiting for us but don't worry I have a lot of control over this so I won't drop you in too quickly anyway as you go down you can see the same distortions the same Einstein ring but if you look to the left and the right you can see the plane of the galaxy as we fall closer and closer the stars begin to turn blue this is called the gravitational blue shift as you are falling into the black hole it's gravity field is pulling the photons down from those external sources so they pick up energy so the red photons get shifted towards blue photons and everything starts to look blue now we're sitting just above the event horizon and the only way we can see the universe is a point of light above us but thanks to my godlike powers I will be able to pull you back out despite their crushing forces of gravity as we come out note again the stars begin to change back from blue through to their normal colors now the opposite is true of light escaping from near the black hole that light has to travel upwards against the gravitational force of the black hole and in so doing it loses energy and so it will change from blue towards red and this is called the gravitational redshift and now we are orbiting the black hole we are orbiting at a distance of three times the Schwarzschild radius now the schwöre shield radius is a really important number it's defined by the mass of the black hole and the important thing to know is that the choix radius is the event horizon that's the point of no return but at three times that distance that's the inner most stable circular orbit this is the point at which you can have a stable circular orbit but below this it is no longer possible to orbit on a stable circular orbit there are possible other versions but your orbit is highly likely to be unstable where you will either get kicked off to infinity or fall into the black hole at this perilously close altitude the Einstein ring has become an Einstein horizon also the stars outside are blue shifted but I'm going to point out that this simulation is missing the Doppler shift so the stars that we are moving towards should be blue shifted and the stars we're moving we're from should be red shifted and it should be quite substantial because when you're this close to the black hole you are moving at a significant fraction of the speed of light thanks to my godlike powers we can get even closer to the black hole this is just outside this photon sphere that is the region where you have to be moving at the speed of light to orbit the black hole and yeah there's normally no stable orbits for physical things in this distance but again I'm I've got you covered here so ya know we see the horizon around us that is the Einstein ring and then there is just the dark blackness of the black hole beneath us I've got this set up with an orbital period of about 30 seconds which would imply that this is a supermassive black hole with hundreds of thousands maybe even a million solar masses now many black holes are much smaller maybe four or five solar masses and for those the orbital period would be measured in fractions of a second so again let me use my godlike powers to reduce the size of this black hole and therefore increase the orbital period so you can get an idea of what it would be like orbiting a black hole that maybe was only about a hundred solar masses where the orbit period is a fraction of a second yeah I hope you aren't doing this in VR and or if you are I hope you've got a sick bag sitting around you're why the black holes have showed you so far do not have accretion discs so you could see the stars around them once you add the accretion disk the light that's coming off it just overpowers everything else that's there but it does provide an interesting reference point for these fly paths now if you look around you you can see the edge of the disk can defer a certain level but as you fly over the top of the black hole the whole disk lifts up around you because at that point if you imagine the light from the edges are has to get curved down towards you so everything seems as if it's being lifted up when you're in this when you're sitting on top of this black hole and of course once you have an accretion disk you also should be thinking about red shift and blue shift which means one side of the accretion disk would actually appear brighter than the other regardless I hope you found these visualizations interesting you can get them with space engine it's all free in the Internet I'm Scott Manley fly safe

Channel: Scott Manley

Views: 508,206

Rating: 4.9342256 out of 5

Keywords: black hole, 360, vr, space engine, relativity, falling, orbting, event horizon, schrawzschild

Id: JDNZBT_GeqU

Length: 6min 14sec (374 seconds)

Published: Thu Apr 11 2019