 Hello there everybody My name is Phil Lamar and I want to welcome you to NASA's ask the astronomers live Where we have live astronomers not robots or holograms Here to answer your questions about the universe Now you can put your questions for our scientists in the comment section of the stream of whichever platform you're watching it on and If you want to find out about any upcoming shows like ours or other shows Or just see lots of fun astronomy videos go to the universe unplugged website right there universe unplugged org and When you ask a question, please try to include your social media handle that way We know it's not just coming out of the ether All right today. We are talking to two brilliant astronomers who have been studying brown dwarfs Let's say hello to dr. Davy Kirkpatrick and dr. Jackie Faeherty Davy You are from NASA's IPAC center over at Cal Tech in Los Angeles, correct? That's correct Why don't you tell us well? tell the audience a Little bit about yourself and and what you're working on these days Well, I've been working my entire career on low mass stars and brown dwarfs is research And I've been finding those very interesting for quite a quite a long time and as part of my other day job I actually work on quality assurance for images and data coming out of some of NASA's infrared missions excellent and Jackie Thank you for being here. Hi. Yes. I do you work at the American Museum of Natural History Right. I do correct and you and you know Davy I do know Davy Davy is actually my academic grandfather, which I'm not sure he loved me saying grandfather, but Davy was the advisor of my advisor in grad school and so we're Academically related to each other not actually genetically in any way she's performed It's only that, you know, we're related academically I Academic Grand Yes, what would be the Grand of Godfather? No, I don't know I don't know that we have that. I mean people do talk about cousins and and Like distant relatives people will trace their academic heritage all the way back as far as they can get in You know famous PhDs, you know, you can go back 200 years and see how well you're related to like Eddington That's six six degrees of Isaac Newton Wow, all right our topic today is brown dwarfs which Don't know for anybody who gets confused and thinks that they've suddenly like gone off onto some D&D twitch stream. No, we're still talking astronomy Davy, could you please tell the audience and me? What brown dwarfs are? Yeah, so if we could have video number two, please So brown dwarfs are objects that form like stardew stars do so if you look at a cloud of collapsing gas for example and this is a Prediction shown here and we've got the time in the upper right-hand corner just ticking off about a thousand years per second You see that as this cloud of gas collapses under its own gravity You get these concentrations shown by the yellow dots and if these concentrations get hot enough in this interiors They will start to form huge Hydrogen into heavier elements and those are things like stars stars like the Sun that will burn for billions of years under their own light or under their own energy, so they Actually are seen at the same temperature and at the same luminosity for billions of years but there are some objects and there are some other objects in this a Prediction here that are also little yellow dots But they don't quite get enough mass and they don't get hot enough in their interior To actually start fusing hydrogen into heavier elements So they don't have that internal energy source that will keep them burning for billions of years And those are the brown dwarfs and we think brown dwarfs form roughly Around 72 Jupiter masses or lower and everything above that In mass above 72 Jupiter masses is a star and I will point out that for the savvy listeners out there There's another set of definitions that is used sometimes for for brown dwarfs and that is a mass-based definition where they say Brown dwarfs are things between 72 Jupiter masses and 13 Jupiter masses and anything below 13 Jupiter masses It's called an exoplanet, but Jackie decided for this particular show. We would use the older definition Which is the one based on formation Interesting so okay, so brown dwarfs are these gigantic Not quite stars Mm-hmm correct, so it's like if you're a big developer and you I built this amazing building And I want all of these people to move into it and no one ever does Like the shopping shopping center that's empty down the block I want to say I'm gonna say the definition that I very much dislike or the Very much dislike because I feel like it it should actually be said and then refuted and that is that brown dwarfs are failed stars And and there's even there's conference proceedings There's books that were written when people were trying to like figure out these objects and the titles are Failed stars and their properties, but I really dislike the word failure in anything So even though in some and that also implies that they had some preference to be This idea that these objects that are that they should be stars You know what I'm saying like there's nothing about them that says they should be anything They're very good at what they are and what they are are objects that are existing in space Like if one of the Jonas brothers wants to be a doctor he is not a failed Jonas brother You shouldn't assume that everything should be a star So sometimes I will call them overexcited planets because people love the word planet more But really I don't know that I even agree with that right because because that just means that the planet is the thing to be I don't think I think they should be good with what they are They are brown dwarfs that is what they are and we love them for what they are and and you guys work on Analyzing brown dwarfs are discovering them. I mean are they hard to to find Yeah, so I can answer this one is Davey and I actually I mean Davey should say something to this too because Davey was around for all of the early-day searches and so what happened was in You know, we kind of were figuring out stars through the early 1900s And then we get to the point where we're trying to figure out What's the lowest mass thing that fragments off and it's still fate basically forms like a star so what's that lowest mass thing and What we came upon was this idea that I bet you can get to the point where you break off and like Davey says you can get To 75 Jupiter masses and at that or 72 Jupiter masses You get to the point where the object starts to look a little different, but the thing is it's really cold So it's giving off the majority of its light in comparison to stars It's giving off the majority of its light at a wavelength that our eyes can't detect It's ever at least our eyes are not sensitive to at all So they give off the majority of their light in the infrared so you kind of had to wait until infrared technology Was really ramped up in order to start finding these and that's basically where Davey comes in as one of the first true brown dwarf hunters or brown dwarf discoverers in in large bulk Was the infrared technology just burgeoning when you began doing this work, Davey? Yes, really in fact the the earliest infrared detectors that we had back when I was in grad school We're one pixel by one pixel. So essentially one pixel array And it was really hard to get very much of the sky map when you have one pixel You can imagine having a digital camera these days with a single pixel We take a portrait of somebody so we had to wait for the technology to actually give us large enough arrays to actually tile the sky and Where does the name round dwarf come from does it come from the fact that they are so cold that they're not giving off red heat Well, it was really back in the day when they were trying to figure out what to call these objects People were saying well, they they cool down steadily with time. So they're kind of you know kind of red They're you know mostly infrared type objects, but they'll eventually go black But the problem was that red dwarfs was already a term that was used for mDwarf stars and Black dwarfs are the end products of white dwarf evolution when they go completely cold. They will be black dwarfs. So Jill Tartar who's a scientist at the City Institute came up with the idea of let's call them a color That's not really a color and just call them brown because we really don't know what they're supposed to look like Right. What's just stuck is the term Interesting interest. So, okay, so brown dwarf was in relation to all the other color designations that already existed at the time Right. Wow. This is fascinating that this is a relatively new arm of astronomy And you're saying and you're saying that now you have infrared technology. You're not looking at one pixel at a time you have wide arrays of The galaxy to look for brown dwarfs That's correct. Yes. And in fact, we have some of these capabilities now Spacecraft so up above the Earth's atmosphere We can get to the wavelengths that we can't reach from the ground because of our atmosphere absorbing that light and in fact The as Jackie was saying out in the infrared where most of these objects have their peak flux That happens to be an area that we can't really observe very well from the ground because of the Earth's atmosphere So not only do we have to develop these infrared arrays in a large format? We had to get them up out of the atmosphere as well So that's where spacecraft like the wise mission the wide infrared field survey came into power You know one one thing I want to note on this too because sometimes I get asked this question where people get excited They're like, ooh brown dwarfs. Can I go outside and see one and I have to say No Not even the closest brown dwarfs not even the ones that are basically Spitting distance away from you. You can't actually see them with your eye because They're too faint. They're they it's like they're literally invisible to you. So unless you have infrared eyes You're not going to be able to see these kinds of objects. You need you need telescopes You need nice detectors in the infrared and then we can start seeing them So we can tell you that they're all over the sky But we don't have any I can't tell you where to look because you can't see them with your eyes, okay, so so I would imagine Working with things that are invisible that of course makes them difficult to find Are there other difficulties in terms of the work you guys are doing in terms of identifying finding in the sky? Yeah, I'll mention that part of why I think we're we're excited to talk to you today, too Is because Davey and I are a part of this project. It's called backyard worlds Colon Planet 9 and this is a citizen science project Which means it's open for anyone and everyone that wants to get their toe in the in the pool of Scientific research to come on and help us locate brown dwarfs now because like I said You can't see them with your eyes. We need to look through images from telescopes And and then there's like other tricky things about this So astronomers have been working on the issue or the the search for brown dwarfs for many years now But they're one of the ways that we can find them is if we look through images That are taken with enough time between them That will actually see the brown dwarfs move and the reason for that is that Objects that are closer to you objects that are closer to the earth to the Sun to our solar system We'll actually be able to detect their motion through the galaxy if we wait a couple of years Sometimes you don't have to wait a couple of years and so you can blink between images It's actually the way that Pluto was discovered in our solar system It didn't need to wait years for Images between Pluto you could wait days in between and see an object jump around in our solar system But we look through images loads and loads of images infrared images and we ask citizens to help us Detect objects that are bright in the infrared and that jump and so actually we have a video for this if you pull up Yep, video one. This is actually this is actually something amazing I'll say this software that generated this or the the viewer that generated this was actually developed by someone named Dan Castleton who's a citizen scientist that works with us and what it's doing is it's taking several images Over I think like a seven or eight year period here And what you're seeing is most of the black dots in this Don't move it all those are stars that are so far away that we cannot detect their motion in the galaxy But if you notice at the center of this blinking image here There's a black star that moves back and forth and that orange dot that also jumps with it And this is a little family that we discovered that actually some citizen scientists discovered of that black object Which is barely a star. It's almost a brown dwarf actually and that orange blip That's jumping back and forth. That is a low temperature Cold low mass brown dwarf that is very close by to the solar system And it was discovered by citizen scientists. We followed it up and we actually wrote a paper about this So we've been using the eyeballs of citizen scientists to help us look through Thousands and thousands actually at this point probably almost millions of images of the sky To find more of these objects That's amazing. So Davey other than what Jackie just showed us. What else has the crowd helped you find? Well lots of interesting brown dwarf candidates that we've been following up at various telescopes across the world as well as other things too like white dwarf stars, which are the remnants of Actual stars that have gone poof in the night and they've expanded all their thermonuclear fusion in the core and have Turned into stellar remnants But they find found lots of other interesting things too like brown dwarfs that don't fit their idea of what brown dwarfs should really look Like as well. So we found some things that are not Exactly what we expected based on the theory that these objects should look like and again She just mentioned Dan Castle then who built the wise view viewer But he found something that we've been terming the accident and the accident is an object that moves across this guy Just like in that's that Jackie was showing that movie It's clearly got proper motion compared to the background stars and proper motion just means that if you've got a very close object You can see it moving relative to the background stars that are relatively Still in space because they are so far away and he found this by accident He was looking at something else and noticed in the corner of the image. There was this other object moving He's like, oh, wait a minute. That's moving. It's gonna be pretty close, right? But it didn't have this orange color like the object that Jackie showed So not only are the citizens like just finding things like brown dwarfs and white dwarfs and other objects We already know about but they're finding some things that are not like anything we expected Interesting so that might change what Jackie's scientific grand grandkids study It's very true very well be changing the face of brown dwarf science, but they would also be Davies great great great grandkids That's funny well now Jackie in the video you were showing us the This the brown dwarf that was closer to us in relation to the what is this new information that we're getting Tell us about our neighborhood of the galaxy Yeah, so Davy is gonna talk about this too, but I want to use a video So if we could turn video three on This is actually a video that I rendered using some software called open space, which is a visualization tool that we're developing in part at the American Museum of Natural History And that's the earth we're pulling away I've turned on all of the constellations for you all 88 of them So you can see the zodiac constellation of leo which is actually red because it's zodiac constellation and all of those red Objects are Brown dwarfs now we're pulling away. We were close to the solar system And now we've pulled away all of the lines have now kind of separated off because those are the lines connecting constellations We're out here now with this grid which takes us out to like 100 light years or so away from the earth and that Map that you're seeing all those red Objects there and this grid this hundred light year grid is for scale for you with stars that are There's the stars are also in here. See season is white those objects are in The are all have all been mapped and are telling us something about the locations Of the lowest mass objects of star formation What we call the basement of star formation And what we've been doing is trying to take all this information of objects that may have been missed by astronomers surveys that were garnered from participation from citizen scientists And counting them all up and seeing just this view as we come in on the earth with this like Realistic view of what the earth might have looked like on whatever day I rendered this video That would be your night time sky view if you could have brown dwarfs in it because you could see them That would be in part your view Interesting interesting Now davie, I noticed when you were talking about the definition of brown dwarfs you were talking about jupiter mass How do brown dwarfs compare to the large planets in our solar system like jupiter? Well, I think this is going to surprise you Phil If we could see image number three So we talked about brown dwarfs having masses anywhere from 72 jupiter masses down to a jupiter mass or even lower But funny fork of physics. Um, and these are all to the same scale here. This is an artist rendition by robert hurt from ipak On the far left. We have an image of the sun to scale And the four objects that are shown to the right of it are an m dwarf star A couple of brown dwarfs that are various Temperatures one little bit warmer than the other that one's redder and then we've got the purple brown dwarf next to it And then the planet jupiter. Well, these are all to the same scale. It turns out that low mass stars Brown dwarfs and the planet jupiter all have essentially the same size But the weird thing is that these masses are vastly different The low mass star the one next to the sun there could have a mass as high as say 100 or 90 jupiter masses something like that The red brown dwarf next to it might be 70 jupiter masses the one next to it the purple one could be 30 jupiter masses And of course jupiter itself is only one jupiter mass So it's kind of one of the reasons these things are so hard to find is that You know, not only are they're faint, but they're faint primarily because they're tiny Interesting, okay, so Yes, okay when because initially when you said 72 jupiter masses I guess I just sort of overlooked the word mass and was thinking volume But no, it's it's it's so the volume can vary But the or the volume can be relatively the same But the mass varies widely widely that's that's amazing. All right. Um Oh wait, we're sort of the halfway mark So, let me just say for anybody who missed the beginning of the show or if you're just joining us in the last, you know Minute or so We are chatting with jackie faraday and davie karpak trick About the latest results about brown dwarfs in our nape in the neighborhood of our sun Now let's let's see if we have any audience questions Yes, here we go this is For both of you to answer Because we we want to know your origin stories What is it that got you interested in studying brown dwarfs? And I guess we'll go chronologically davie you go first Start with grandpa. Yeah Well, when I was in in grad school and even when I was an undergraduate, um I started hearing stories about the The nemesis hypothesis and the nemesis hypothesis was um Trying to explain the fact that it that appeared that these mass extinctions on the earth Happened cyclically meaning that every 26 million years. There was another mass extinction event where plants and animals just died off in giant numbers And there was this issue of I believe it was science magazine where they had a bunch of people come in and say Write papers about what could possibly explain this and the one that really caught my eye was the one where they said Well, maybe the sun has a stellar companion in this very long elliptical orbit That only takes it Into the inner solar or into the solar system environs about every 26 million years Upsets the oar cloud and the oar cloud is a Area of the solar system way in the outskirts where all these ancient comets live And if this star is Plumbling pummeling through that area of space it can send comets into the inner solar system And those comets can pummel the earth and you know do all kinds of habit to plants and animals on the surface, of course Wow Well, the thing that really struck me about that was The sun could have a companion a star. We don't know about what this is crazy And you know the astronomers didn't run around and throw their hands up and say oh, this is crazy, too. They're like, yeah could be I'm like Wow Here it is 1980 something and we don't know if the star is a double star I mean our sun is a double star or not. That was just that struck me as it's just incredible So, uh, I got interested in what other discovery space there might be out there And that's when I started learning about these theoretical entities called brown dwarfs Which were thought to be an in product of a star formation that could be very faint and very cold And so that's what I want to study. I kind of like that idea. Let's go after the brown dwarfs and see if they actually exist Wow Okay, that makes sense and and i'm pretty sure somewhere riddly scott is working on a movie called nemesis hypothesis I don't know how that movie hasn't been made Right, it should have been made by now totally It better be scientifically accurate when they do make it I think Well, if they wait 20 years, maybe the science will change but But in the meantime, let's go back in time and find out jack. What got you interested in studying brown dwarfs Yeah, well actually grandpa pick Kirk factory here is one of the reasons why I Chose brown dwarfs and that is one of the little known the lesser known things about science is that And you can choose anything in the universe to study. There's mysteries about everything. There's mysteries about earth That we live on that we can walk around and study and you know pick up rocks and and learn about them and but So everything is open to you when you start graduate school It's and I'm sure you can get excited about everything because everything's got some good stuff about it But there's also this other aspect which is the people And whichever subfield you choose of science You're probably going to be within that subfield or closely related to it Whatever it is that you've chosen as your object or area of study for years of your career And when I showed up in brown dwarf science or when I showed up in graduate school Brown dwarfs were very young still in the sense that they'd only sort of just been Um We only just started studying them observationally. So there was a lot that one could do And the people that were there Like davie were awesome They were really nice And it didn't feel like super cut throat and competitive. It felt welcoming And I loved the idea of entering a new field a new field meaning these objects were kind of new to our Our cluster of objects that we were studying And the people that I want to spend my time with like you can ask davie We spend a lot of time together in meetings right now Um, so I think I picked the right choice That there are the people I do enjoy being around so From that sense, this was the choice made so that my days were Very nice from all the objects we were studying but also the people I get to spend them with are pleasant There you go Yes, your scientific community. Yeah, actually I'd I'd be very curious to know if there is Of personality distinction between people who choose relatively new arms Of science versus, you know, the old I I'm just imagining Isaac newton teaching some kids, you know, like all right, we got this new thing called gravity Yeah, I want to study that Wait, you know, I want to answer that because I think it actually has some relevancy of Gender equity in science. So what I've seen which is interesting is wherever there's something new When it's like no one's quite doing it yet um Women have more of the opportunity to kind of pop in and become the leaders So you see this in exoplanet science right now that exoplanet sciences is while it was going on for a little bit Of time where people are really searching once it started to explode With like the kepler spacecraft and all of the discoveries there There's a lot of women that were involved on the ground and have built careers on this and in brown dwarf science We have a great collection of of fantastic scientific Of women stem scientists in brown dwarf science and it was new and there was opportunity You know, like I feel I I feel also really good that the people that were there didn't get selfish and saying like It's mine. It's mine. It's mine. It's very welcoming And it was an open and so when you have new Bits new a new subfield opens. It's also an opportunity to not have the old guard there That is there that's protecting it all and deciding that you you're not going to let everybody in that could be let in Right and and you're not fighting against this the idea of oh You don't look like a brown dwarf scientist because there's not some old etchings of you know Someone from ancient Greece with a giant beard and robe, right? Right, you don't have that standard vision So I might be what you think of when you think of a brown dwarf scientist now In fact, you are Oh good, and I'm wondering I'm wondering why I'm wondering why Davey's hair is so short I've been cutting it myself during the pandemic and I have no idea what I'm I Scientific precision all over there All right, let's see if we have do we have any another audience question? Yes. We have one from tom bickle Oh, this is interesting. Could there be Closish brown dwarfs that are too faint for wise to detect Do you want to take that one, David? Yeah, sure. So the coldest brown dwarf we currently know is know is something called wise 0855 And that one is only 250 degrees Kelvin Which means that if you translate that into Fahrenheit, it's about minus 10 That's a cold It is only 2.3 parsecs away, which is like something like six light years And there must be lots more of those I mean, why would the only very super super cold brown dwarf be, you know, just right in our backyard But you could imagine something that's 200 Kelvin or 150 Kelvin even colder than this thing It could be sitting As close as Barnard star or as close as Proxima Centauri. We wouldn't be able to see that all even with wise So yes, this is absolutely possible That's it's I mean, it's so fascinating the fact that You know, because a lot of us think are are still in the ancient idea of studying the stars means walking outside and looking up with your eyes But you guys are detecting and taking in information on so many other levels now But apparently there are still limitations even to where we are now Well, I I want to say something on that too is that Um, you walk outside and you think you're looking at all the stars But did you know that when you walk outside and you look up And you say, okay, I'm going to look at the closest star to us. I want to see the closest star You can't see it. It's too faint The closest star is Proxima Centauri and it's right at the limit of the human eye So you're not even seeing the closest star This is what should astound you about your view Of the universe while it's gorgeous and I I absolutely implore everyone to go outside Look at the nighttime sky get odd of the wonder and all the da-da-da-da-da But then think about the mystery of what you're not seeing And so that's that's like what Davey and I are into too because There's so many of these little balls of gas that are out there these brown dwarves That have fascinating weather phenomena that may very well be closer than the closest star That you can't see because they're just so faint And I'm certainly driven by that mystery by the mystery of our own solar neighborhood Like what else is there? I'd love to know I love that Oh, here's another question that I have for you guys How can viewers join in on the brown dwarf hunt? Yes, you can join right now. You can join by going to backyardworlds.org That is our That is the project It's a zooniverse project Meaning zooniverse is this great portal which pulls together projects That bring citizens from anywhere and everywhere to participate like I was saying dip your toe in the scientific research world There's loads of projects to choose from on zooniverse But we are the one that I would tell you to choose And come join us on our search for brown dwarves Backyardworlds.org check us out. It's a great project and once a week we have research We have calls and the citizen scientists join in I would say it's really fun, right Davey That's right We have one on a Thursday mornings our time and also one on a Saturday mornings for people who can't make during And you sit down you talk to your other colleagues on You know your armchair astronomers as well as some of the professional astronomers who join in as well So it's I know people get a lot a lot out of the fact that they hear the banter back and forth between the scientists because they don't see science Working in other aspects because you just see press releases and things but they get to see how the sauce is made Right, right Oh, that sounds amazing. So yes Anybody out there who's got some time Thursday and Saturday mornings you can help Find out information about our universe at backyardworlds.org You know what if we could show an image number five I just want to highlight. This is something that the citizen scientists also do this is an artist's rendering Um, one of our citizen scientists his name is billy pendrell He I want to say he drew painted on top of some other drawings This rendering of that first video that we showed of those two objects bouncing back and forth This is the discovery of a hotter object, which is the yellower object in the more distant Not in the foreground and this purplish object, which is the colder object the brown wharf And billy drew it and I love seeing this also, you know, bring your talents your talents outside of research to us Artistic talent is underappreciated in the sciences Um, we would we would love to bring you into the research fold as well Just like billy who now draws a lot of things for us. He's come up with a lot of really cool renderings Excellent. I love that That's you've got a volunteer fire department. We've got a volunteer astronomers. I love it. All right before we finish up, um And ask you guys for the final I just have to say that Jackie when you were talking about the mystery Of the universe and how brown dwarfs are an example of that it really Triggered something for me. It was so amazing because so many times you hear people talk about You know astronomy and looking up into the sky makes me feel insignificant But the idea that no looking up into the sky and thinking about what you're not seeing Makes me want to go get a master's degree Find more stuff Yeah Like let the carrot be when you go outside and you see a really gorgeous nighttime sky and then flip it and think Well, this is awesome. I mean What am I missing from here and what you're missing is a lot Wow, like so much stuff out there Exactly. Well, I guess maybe we've but do you guys have any other final thoughts before we wrap up? That you would like to share with our audience The there's one other thing that I wanted to show which i'm super proud of And that is um, if you bring up image number six So what this is is um, I worked with an artist whose name is amanda Thing body ha kia has a really hard last name But that's her sitting um at the the base of this mural. This is a mural that exists on a Building wall in brooklyn and it is an homage to brown dwarfs So the colors that you see the reds and the blues are supposed to reflect the two different kinds of brown dwarfs The redder ones are these l types that have very cloudy They have pretty thick clouds and the blue colors are the lower temperature What we call the t types that are very methane gas dominated and as I like to describe them Brown dwarfs are windows on the universe and so you can see the windows opening And it was also an homage to women in science Um, which i'm very proud of how it looks. I think she did an amazing job of depicting Emails as brown dwarfs, uh, and it's called a cluster of enigmas And I would just encourage anyone that wants to see it that might be in brooklyn or maybe when we all get a chance to travel again You might you know, take a little side trip These are always fun little things that you can figure out that are in a city But this this mural that is on is at a medical center in fort green brooklyn Uh, you can go look at this and take it in and and think about the brown dwarfs Think about what brown dwarfs are of what they might mean to you They're certainly to me a gateway into science. They're my they feel like Sort of the my like, you know, my family my family members are now brown dwarfs Even though that also sounds a little weird, but I'm just gonna go with it Davey, how about you final thoughts to share? Well, we could actually show image one and we'll give you a little indication of what our thursdays look like when we have our our group of citizen scientists get together so These are really fun discussions The scientists learn a lot from us. We actually learn a lot from the scientists. I look forward to these every week And uh, really if people want to get involved, please get in touch with us via backyard worlds and uh We'll put you in touch with a greater team There's a lot of people out there who want to be looking through the sky Looking for new objects and making discoveries of their own So Please join the team Excellent Thank you. Thank you. Dr. Jackie ferdy. Thank you. Dr. Davey Kirkpatrick for sharing your expertise with us and introducing us to the intricacies and mystery of brown dwarfs And thank you to you guys for joining us and learning um about our son's neighborhood Now you can see this video as well as all of our other universe unplugged videos at universe unplugged.org Um, you just click on the link in the comments. You can subscribe on youtube And uh, then you will be the first to know when our next video comes out We try to do them once a month, but you never know and also follow us on facebook to catch the live show And until that next live show whenever it is i'm phil lemar and this has been ask the astronomers live Thank you guys very much