Closest black hole to Earth found & the mystery of Fast Radio Bursts solved? | Night Sky News May 20

welcome to another night sky news everybody there is far too much to talk about to waste time on introduction so let's get straight into it with what you can see in the night sky in this coming month so the 23rd and 24th of May my usual favorite thing to see in the sky a toenail moon with Venus but this month mercury as well this is gonna be a lot easier to spot on the 24th the rather than the 23rd because and the 23rd the moon's gonna be the barest sliver of a crescent near Venus and also very close to the horizon so on the 24th a little bit bigger and also have risen a little bit higher as well so you can use the moon to then find Venus which will be incredibly bright you shouldn't be able to miss it and then once you're there you should be able to find mercury from there as well could make you would just be that little bit higher than Venus and you'll need that because Mercury's so much fainter than Venus and when it's out the Sun is still sort of lighting up the sky a little bit during Twilight so if you are in a very dark location you have a chance of video to see it with the naked eye but otherwise just you know crack out the binoculars and see if you can find it mercury will get easier to spot as the week's go on so by the 3rd of June he'll hit what's called its greatest elongation which is basically the furthest point in the sky that it will get away from the Sun it's the moment which mercury the Sun and Earth make a nice right-angled triangle as for Venus though it is getting closer to the Sun from Earth's perspective anyway all the time now so this is actually the last chance we're really gonna be able to see Venus this month by the end of the month it will have actually set because it will be so close to Sun you don't even ever stay during the day and the Sun is too bright to do that so if you love the toenail Moon or the tiny crescent moon as much as I do and Venus together make sure you spot it on the 23rd and 24th of May then for the early risers by the 12th and 13th of June the moon which will be doesn't just pass fall by that point will be very close to Mars in the sky it will also be very close to sort of Saturn and Jupiter which should be sort of just up and to the south of it and it's a great time to try and use the moon to spot Mars Mars will have that sort of distinctive reddish tint to it Jupiter would be incredibly bright in the south and against that close to it but not as bright seen if you're not sure what you're seeing is Saturn or Jupiter or Mars then what you're gonna need is one of those night sky apps which is why this month's episode is actually sponsored by redshift Sky Pro this is a stargazing app that once it knows your location you can point it in any direction in the sky and it will tell you what you are looking at it's a great way to find objects like planets comets or even nebulae but also to make sure that what you see then this guy actually is what you think it is as well it also has a red light feature to turn your phone screen red so that you don't ruin your night vision whilst you're out stargazing which is actually one of my favorite features of the app it's available in ten different languages from both the Google Play and Apple app stores and from today Wednesday the 20th of May until Sunday the 24th of May they're actually having a sale so instead of costing you eight pounds ninety-nine it only cost you seven pounds 99 to download it so if you like the sound of that the link is in the description next I want to talk about something that people probably don't stop to think about very often and this will depend on your location sort of on planet earth you know depending on what latitude you're actually at but for sort of the mid latitudes of the Northern Hemisphere anyway as we get into sort of the middle of June this is when your earliest sunrises are going to be you can see this for your specific location at websites like this this is time and date calm so you can see here for Oxford for the earliest sunrise is 4:45 on the 15th to the 18th of June but the actual longest day is not until the 20th of June ie the summer solstice now the further north you are the closer to the actual Solstice your longest day will fall but then the closer to the equator you get the more pronounced the difference so for example in Honolulu in Hawaii in the States though earliest sunrise there is actually late May and then actually their latest sunset don't come until early July it all comes down to how we measure time and how we measure what a day is there some definition obviously is that a day is how long it takes for the earth to spin on its axis but the thing is you need a reference point to decide at what point the full day has passed so a good reference point to use would be mid day now talking about 12:00 p.m. during the daytime I'm talking about the point at which the Sun reaches its highest point in the sky so in fact the time that it takes the earth to rotate a full 360 degrees is 23 hours and 56 minutes but the time it takes for the Sun to go back to the same position in the sky is 24 hours those extra four minutes come from playing catch-up to get the earth to rotate just that little bit further round so that the Sun is in the same position at noon again but also this is just an average because the Earth's orbit is also not a perfect circle it's an oval-shaped so sometimes we are further away from the Sun and we're moving a little bit slower and sometimes we're closer to the Sun and moving a little bit faster it means that the difference between two successive solar mid days is about 40 seconds shorter in July and about 20 seconds longer in January these ever so slight differences you know if just a minute or so meaning that our clocks the earliest sunrise does come before the Solstice despite the fact that if you were truly on solar time on the sun's time there I've bang on schedule right enough night sky chat let's talk about all the cool astronomy news that's been happening this month because not only do we have a possible unsolved mystery a fast radio bursts but we also have some black hole news so I usually start this segment off by showing a really cool image that's been taken but like a telescope or a space mission but how about this month we instead start with a piece of audio so on the 9th of April ESA's bepi Columbo mission which is currently on its way to mercury did a fly past the earth for a gravitational boost in energy from us then on the 5th of May this month ESO actually released that data but what they've done is sauna fied it so what they recorded was the vibrations detected by the accelerometer on board the spacecraft which when they're in their normal form are a very low frequency it's not audible to humans at all but what they've done is play with the frequency so that we can actually hear it and then also condense about an hour's worth of data into sort of a minute as well so what you can hear there is essentially bepi Colombo's vibrations as it moves through space so one of the ISA scientists on this mission who's called Carmelo magnifico which is a great name I'm kind of jealous compared it to putting your ear to a railway track and sort of listening to see if the train was coming which is a beautiful analogy if not a recklessly stupid luck to put your ear to a train track moving on from fun data sonification now I'm getting a little bit ahead of myself here but I figured people would want to know that this was happening before the actual fact so the first crewed mission of SpaceX's Dragon capsule is due to take place on May 27th it will be taking astronauts up to the International Space Station for the first time it's been tested uncrewed many many times passed all the tests and this will be the first crewed one it marks the first time that astronauts have been launched from US soil up to the International Space Station since 2011 when the space shuttle program was retired so it's been a long time coming they've been using the Soyuz capsule in Russia for many many years now which is very old seventies tech so they've needed something new for a long time NASA is somehow managing to coordinate all of this despite the pandemic and the lockdown you know they're all working remotely you know Mission Control is now the spare bedrooms of living rooms obviously there are some very critical personnel still on site there's only a very few people exempt though and it's kind of strange to me that this kind of stuff is still happening during the pandemic I'd say what if I was an astronaut onboard the International Space Station right now knowing that two people from Earth were coming up I want to know that they've been quarantined and tested the hell out of before they came to my space station because the last thing we need after the two months we've all had is kovat in space alright on to my favorite topic now of black holes so if you had asked me about two weeks ago where is the nearest black hole to earth would have said why it's V six one six menorah sits about 3,000 light years away and it's orbiting a star that's just a little bit smaller than the Sun you know we've detected x-rays coming from it as far back as 1917 in 1994 we worked out the mass of it and found out that you know it was far too big to be anything but a black hole but that no longer holds the title anymore because in comes hr6 eight one nine in this paper by Rivini as' and collaborators this month so this is a black hole not just orbiting one star it's orbiting two stars it's actually in a triple system it's about 1,100 light-years away so about three times closer than V six one six one Asura so talking about before but this wasn't known to be a triple star system people thought it was a double star system because you could actually see the two stars and so it was included in a study of double star systems that these authors were doing with the 2.2 meter telescope at esos La Silla Observatory in Chile bar we see for this system when they observed it they found that the orbits of these two stars just didn't make sense at all if there was only two stars there at least there had to be a third object in that system now they couldn't see a third object but that doesn't automatically mean that it's a black hole it could be something like a neutron star or a brown dwarf something like that they just figure out was its mass and you do that by sort of saying okay well I have all of these possible three body systems of all these different masses together and which one best fits what I've observed and they found the one that best fits is if that unseen object was 4.2 times the mass of the Sun ie a clear black hole like it couldn't have been anything else it was too heavy to be anything else but a black hole now this would have been noteworthy anyway because it was the closest black hole to earth I mean I am still secretly hoping that this hypothetical Planet nine that's supposed to exist this also sim is actually a tiny primordial black hole that's like the size of a tennis ball just because I want or system to have a pep like call but you know that hasn't been proved at all yet so you know I'll keep dreaming with that one but there's two reasons why this result is also very very cool on top of the fact that it's the closest black hole to the first one is that the stars that it's actually orbiting around are visible with the naked eye like most cool things in the sky though it's visible from the southern hemisphere and not the northern hemisphere which is so annoying I'm just incredibly jealous of you southern hemisphere Ian's again it's in a constellation called telescope IAM which is possibly the most boring constellation ever it's just two stars joined up with the lives below like a telescope but hopefully you should be able to find it especially where the night sky at like redshift sky Pro again and then you can go outside and look at these stars and know that you are currently looking at a black hole the second reason of this result is really really cool is because we don't tend to find black holes like this black holes that we can't actually see and we've only just infer that there because of the orbits of the stars that might sound a bit weird because you know the definition of a black hole is something we can't get light from at all but the majority of black holes that we know about including v6 1-6 menorahs that i talked about at the beginning that's the old closest black hole to the second closest black hole to earth now is because they're actually giving off x-rays that's all the black hole itself it's the material that the black hole is taking in so the black hole gets greedy if it's all between another star it can drag gas off that the gas spirals around the black coin what we call an accretion disk and it heats up because it's going so fast and it starts to glow in things like x-rays sometimes even radio emission if you get very energetic systems like the supermassive black holes in the center of galaxies you can also see like UV an optical from that accretion disk as well so the majority of black holes we know about are in these x-ray binary star systems and we know of about a hundred or so of those things and not all of them will either be black holes either we think some of them are neutron stars are not quite massive enough to be a black hole but unfortunately that number doesn't match up with what models say for our population of the Milky Way so if you sort of synthesize what you think a huge collection of stars hundreds of billions of stars in the Milky Way would be like and what they do and how they spend the lives how they end their lives how many would be big enough to turn into a black hole haven't even big enough to neutron star white dwarf etc etc you end up predicting that in a galaxy like the Milky Way of a hundred billion stars there should be about a billion black holes as well so the question is whether the models our over predicting the number of black holes or we're just missing a huge population of black holes in the Milky Way which could indeed be true we've made some estimates before given how many x-ray binaries we've been able to spot thinking about you know the distances between stars in these binary and triple systems and which black holes if they formed wouldn't accrete mattes II wouldn't know they're there and we do get appreciable numbers but nowhere near a billion so it's a difficult one but the fact that people have been able to find a black hole in what was originally thought to be a double star system has given people a little bit of hope and this might be another avenue of research that people could focus on in order to try and reconcile these two big issues and I'm just gonna say this now because I know this question will come up in the comments but no a billion black holes would still not be enough invisible matter to explain how much dark matter we think is in galaxies I knew someone would ask that question so I'm just jumping on it now next up have we solved an currently unsolved mystery so in my top ten list of unsolved mysteries I posted last week number eight in that list was what is causing fast radio bursts these incredibly short of the order of like millisecond bursts of radio waves coming from space outside of our own galaxy from all different directions we've detected these from some of which have repeated some of which haven't repeated seen them once and then we've never heard from them again usually when they repeat they repeat with no apparent pattern either and so all the ones who were detected so far have come from outside our own galaxy and we know that they must come from something that is incredibly small because the bursts of energy is so short but also that it must be incredibly energetic because in that millisecond bursts the same amount of energy is released as is released by the Sun in 80 years and there has been so many hypotheses just flying around since these things were first detected back in like 2007 or something that we're trying to explain you know what's producing a fast radio bursts and no one had really agreed yet on what the most likely mechanism was but on the 28th of April this year so I try to radio telescopes detected a burst of radio waves from a magnetar in our own Milky Way galaxy that something like 30,000 light years away and there's bursts of radio waves looked very similar to the FRBS the fast radio bursts that we detect from outside our galaxy so my guitars are essentially neutron stars right the leftover remnants of a supernova where the matter has been crushed down and down and down until all you're left with is neutrons as closely packed as they can go magnet ours there are a special type of neutron star because they have a huge magnetic field like a thousand times stronger than a normal neutron star does and we don't really understand where those magnetic field comes from because nobody knows physics understands magnetic field especially at such high intensities they kind of we just don't see here on earth but what we do see is the effects of this incredibly strong and I see if you ought it actually distorts the shape of the star because sort of the magnetic field and gravity are sort of in constant competition with each other and it's thought that these distortions lead to things such as like starquakes which can then give rise these flare of x-rays or radio waves so on April 27th this magnetar had such a flare possibly from a starquake and that was detected in x-rays by for example the swift telescope and that wasn't anything particularly special a lot of bang stars already do that but the very next day is when that bursts of radio waves was then also detected as well that was had a very similar signature to the fast radio bursts that we detect from extra galactic sources so these radio bursts were detected by the chyme experiment in Canada that's been detecting you know reams and reams of these fast radio bursts from outside our Milky Way and also project called stair 2 which is a radio antenna array that was specifically set up to search or listen for these fast radio bursts coming from the Milky Way itself because people have been hypothesizing for a while that if they're happening in other galaxies then eventually something should happen in the Milky Way too now if you took the signal that both chime and stair to have actually detected and you correct it for the differing distances then yes it would look very similar to the fast radio bursts we detect extra galactically however what they've not done yet is actually compare what's called the spectrum of light you receive in that radio bursts so when you take the light that you receive and split it into its component wavelengths and look at the trace does that look very similar so that's sort of the piece of information people are still waiting for and if they find that they are incredibly similar and that probably will be the smoking gun that says yes it's very likely that man Qatar's are responsible for these fast radio bursts however even if that does happen it doesn't mean that magnet ARS are the only explanation for fast radio bursts it could be that we need another hypothesis entirely to explain the ones that burst repeatedly or maybe the magnets I'll explain the ones that burst repeatedly but don't explain the ones that just have a single flare and then we don't hear from them again so it's actually a mad scramble now to analyze all the data that's been collected so this isn't a paper that's been published and out this this was what's called an astronomers telegram where people basically just put a shout out like hey we detected this thing from this part of the sky and so that's all that's been announced so far that this was detected that it's a known location of a magnetar obviously putting two and two together could mean that yeah okay the very likely origin of fast radio bursts is a magnetar but we don't know that for sure yet but it is a good step in the right direction so I am very sorry to disappoint all of you that we're secretly hoping that it would be aliens one day maybe it will turn out that the weird signals we're receiving from space are aliens that's it for this month's night sky news as always if you do any stargazing and you take any pictures send them my way on either Twitter or Instagram I always love love to see them but until next time friends you know stay home stay safe and happy stargazing I feel like I should have like a cat or something to stroke in this fancy new office chair that I'm certain been in they also had a micrometer micrometer no map magnet Oh meter magnetometer magnetometer magnet magnetometer really doesn't roll off the tongue that was mister black hole please tell us why you had to hide away for so long it's camera that only record straight don't know where I got cut off on but it's times like these your charge your battery man it's times like the 28th of April to radio telescopes scopes Gibbs what am i sorted you

Channel: Dr. Becky

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Keywords: astronomy, dr becky, night sky news, astrophysics, physics, space, science, venus, mercury, moon, black holes, stars, cosmology, cosmos, xrays, radio waves, milky way, binary stars, nasa, esa, bepi columbo, jupiter, saturn, spacex, dragon, ISS, space station, magnetar, neutron star, fast radio bursts, unsolved mystery, magnetic fields, plasma, solstice, sunrise, sunset, CHIME, STARE2

Id: Y81ZjpZS52c

Length: 23min 18sec (1398 seconds)

Published: Wed May 20 2020