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Current time:0:00Total duration:8:18

Video transcript

before we start going off into things outside of our solar system I want to take a few step back a few steps back because I found this neat picture of the Sun over here and the reason why at least in my mind it's it's kind of mind-blowing is because at this scale the Sun is obviously still a a huge object at this scale the earth would be roughly and this is an approximation roughly that big and so for me at least this is mind-blowing because it's this idea that our whole planet everything could fit into one of these kind of plasma flares coming off of the Sun and you can only imagine I mean we can't realistically be there but if you were in some type of protected capsule what it would be like to be in this type of an environment so I just thought this was kind of a a fascinating concept well anyway with that out of the way let's just think about what it means to be at the boundary of the solar system in the last video we explored the Oort belt which was about it started it started a little under 1 light year away from the Sun but the depending on what you view is the boundary of the socialism' it could be something way farther in or it could be something as far out as something like the like the Oort cloud so if you with if the Sun right you know we see these things being ejected but even in unseen ways or unseen particles super high-energy electrons electrons and protons are also being ejected from the Sun at super high velocities 400 kilometers per second let me write that down 400 kilometers per second and on earth we're protected from these highly energetic particles because of our magnetic but because of Earth's magnetic field but if you're on the surface of the Moon when the Sun is on top with wood and you're not on the dark side of the moon and you'll have direct contact with these and yet as you can imagine it not not the best thing to hang around in too long but the whole reason why I'm even talking about these these these charged particles that are coming out of huge velocities from the surface of Sun these are considered the solar wind these are the solar solar wind and I'll put wind in quotes it's really very different than our traditional Association of a nice breeze these are just charged particles that are going out at super high velocities from the Sun and I'm even going into the idea of the solar wind because to some degree they can help us they can help us with one definition of maybe the limits of the solar system and that's the limits of how far the solar wind is getting before it kind of comes in confrontation with the the interstellar medium and this right here this right here shows a depiction of that so the Oort cloud it was way at least the the edges of the dense part of it is way outside of this this is as we saw this is just where Voyager 1 Voyager 2 if we wanted the orbit of Siddhant Sedna it would be something it would be something like it's the the closed part would be something over here and then it would go out but the Oort cloud is much much further out so if you look at this kind of view of the solar system as the extent of the solar wind it's much smaller than the Oort cloud but it's still fairly large so this is right here this Helio Helio pause right here and I got this from Wikipedia this is essentially where the the velocity and the forces of the solar wind are counteracted counteracted that it's been the the pressure is so diluted at this point that is counteracted by mainly the hydrogen and the helium that's in the interstellar interstellar kind of medium that's just kind of out there so this is you know after this point it's not really being ejected out anymore it's kind of being it's there's this kind of pause I guess you could say and Voyager 1 and Voyager 2 is this I have essentially gotten pretty close to people believe that that pause over there and so that's one view of the edges of the solar system there's never going to be any hard edge to it another view would be something like the Oort cloud you know the area where you have the still objects out there and this is all actually we haven't directly observed objects in the Oort cloud we think that they are out there and then maybe the most abstract definition would be a significant influence from the Sun's gravitational pull so all of those ways are to imagine the extent of the solar system but they all kind of leave a gray area for what is and what is not in the solar system but my whole point here what I want to do is start explore a little bit outside of the solar system and just give you a sense of the scale as we just go to the closest star so if we go if we go right over here this shows our our local neighborhood from a stellar point of view and even though these stars look pretty big if you actually were to draw this this this is our this is our solar system right here but clearly it and you know you might be say oh maybe that's the Sun no the Sun if you were to draw it here it wouldn't even make up one pixel in fact the entire orbit of Pluto everything inside of it still would not make up one pixel on the screen right here this what we see right here what we see right here which is a radius it's roughly it's roughly a radius of about of about give or take a Lightyear this is roughly maybe the radius of the Oort cloud the Oort cloud and we saw in the last video how huge that was especially relative especially relative to especially relative to the radius of say Pluto's orbit which is roughly like that and that itself is a huge huge diameter or huge distance away from the Sun and that wouldn't even make a pixel that wouldn't even make a pixel on this diagram right over here but just to give you an idea just to give you an idea of how far we are so you know we're a speck of a speck of a speck inside here and they have a pixel of a pixel in the center of here to make it from our solar system or in particular from from Earth maybe to the nearest star to the nearest or maybe the nearest cluster of stars the Alpha Centauri they're the they're the the nearest cluster of stars there's three stars Alpha Centauri a which is the largest Alpha Centauri B and then there's one that you can't observe with the naked eye alpha Proximus or I think it's Proxima Centauri I think it's what it's called I don't not alpha Proximus Proxima Centauri but that's a much smaller star but that's the closest star and it's about and this what well you can view it is this whole this whole cluster of stars right here and they're the closest is about 4.2 light-years light-years away or another way to think about it if someone were to shine a light on one of the planets and assuming that light could get to us it would take four point two years to get to us or if these guys just disappeared or blew up we wouldn't know it for four point two years and you might say hey that's not too bad we should take a trip over there and and check them out see if there are any other people there that we can meet and and and and exchange technologies with or whatnot but this is a huge distance just as four point two light-years it's an unbelievably ridiculous distance and just to give you a sense the Voyager 1 and 2 we talked about in the last video and we can even see how far they've gotten they've gotten pretty much to the heliopause these guys are traveling at 60,000 kilometers 60,000 kilometers an hour 60,000 kilometers an hour which is the same thing as 17 kilometers per second 17 kilometers per second if we were able to get up to those type of velocities and these guys got up to those type of velocities by leveraging the gravitational pull of some of the larger planets to accelerate and keep accelerating so this is a pretty hard velocity to actually reach but if you were able to reach those that velocity and go straight in the direction of go straight in the direction of the Alpha Centauri system the closest stars to Earth it would take you it would take you 80,000 years traveling at the same velocity as Voyager 1 which is the fastest of the Voyager so it's a ridiculously long time so it's going to be we're going to figure out some some better way to do that