This is the transcript of a chat held at the Slacker Planetarium on May 17, 2007 @ 14:15SLT. Our special guest, Dr. Chris Thom is "CT Hykova" in the chat transcript. The host, Aaron Price (a.k.a. Slacker Speedwell), is "You:" (the one who recorded the transcript.). Details on this chat are available at this URL: http://www.slackerastronomy.org/slackerpedia/index.php/Kavli_Institute_For_Cosmological_Physics CT Hykova: Hi guys CT Hykova: yeah...I'm kinda new here florenze Kerensky: welcome :) You: CT hykova is our guest Dr. Chris Thom You: Dr. Thom is an astronomer at the University of Chicago... You: He is going to first talk about a recent discovry he was a part of regarding dating the oldest known stars CT Hykova: why don't I start off with some background CT Hykova: about how the elements are formed CT Hykova: The big bang forms hydrogen, dueterium, some helium, and a tiny amount of lithium. In fact, the theory of what should be formed (called Big Bang Nucleosynthesis), and what is observed, agree incredibly well. CT Hykova: Most stars just burn hydrogen into helium, fusing the two hydrogen atoms. More massive stars burn hotter, and so they can ignite helium burning, forming carbon, nitrogen, oxygen etc. The hotter the star gets, the heavier things can be fused, all the way up to iron. All of these processes *release* energy, if you can get it hot enough to start the reaction. CT Hykova: After iron, to make heavier elements you have to *put in* energy, so the way elements are formed is different. Instead of fusing two things together, you now just add a single neutron to the nucleus. This is a very different process (called neutron capture)...and can happen veeeery slowly (in stars) or very rapidly (in supernova explosions). CT Hykova: So, uranium and thorium are both elements which are made in the rapid process (r-process) -- they are only made in supernova explosions...because in a supernova, the neutron density is very high, so catching one is more likely. CT Hykova: So if we can observe Uranium, we know there had to be at least one star living and dying before our star, HE1523-0901 was born CT Hykova: So what we did was observe this particular star CT Hykova: and we detected uranium and thorium....and we use a process similar to radiocarbon dating CT Hykova: to measure the age of this particular star Online Tracker: Krude Skall, please say your message on one line and it will be recorded and/or sent. Krude Skall: yeah..ok CT Hykova: and the age for our star is very similar to the age of the universe Online Tracker: Krude Skall: yeah..ok Online Tracker: Thank you, Krude Skall, your message has been sent. Clear skies! CT Hykova: although our measurement is much less precise than other measurements CT Hykova: we know the universe is 13.7 billion years old Xupert Miles: "our star" = the one you're looking at ? CT Hykova: and our star is about 13.4 billions years old CT Hykova: yup CT Hykova: our star is called HE1523-0901 timur Congrejo: are you sure its not 13.8 billion years old? CT Hykova: we observed it for about 8hrs at the very large telescope in chile CT Hykova: well....the accuracy of our measurement is about +/- 2 billions years CT Hykova: but that's still pretty good for this kind of measurement timur Congrejo: wow that accurate CT Hykova: sure CT Hykova: but....keep in mind CT Hykova: that the age of the universe is 13.7 +/- 0.1 billion years old CT Hykova: and that comes from a NASA satellite called "WMAP" CT Hykova: so....our star was made very early in the universe CT Hykova: we think maybe only the second generation of stars....althought we're still working on that Kelly Young: is it very distant? You: Thanks for the summary, Dr. Thom! We'll now open this up to questions and general chit chat CT Hykova: well...distances in astronomy are *really* hard to measure CT Hykova: in fact...they are one of the hardest thing to measure timur Congrejo: have you seen any life on mars yet? Krude Skall: is General Chit Chat here? CT Hykova: so....it's not clear how far away the star is Kelly Young: no parrallax Turnex Morellet: when is the first generation of stars believed to have started .. relavtive to BB? CT Hykova: well...the first stars CT Hykova: were probably formed about 250 million years after the big bang CT Hykova: no...we don't have a parallax unfortunately timur Congrejo: the big bang timur Congrejo: a friend of mine seems like he's a alien, do you know of such existance? timur Congrejo: the rolling stones had a big bang aswell Turnex Morellet: so if this is a 2nd generation star there must have been supernovas before it to seed it? IM: Troy McLuhan: You might want to move - you sat on Max Barney Boomslang: would those first generation stars actually still be observable? wo0uldn't they be "at the center" whereever that is and not viewable as solitary stars? CT Hykova: yes! CT Hykova: the first stars are a very big field at the moment CT Hykova: lots of people are trying to find a "first star" CT Hykova: we think we have found a couple that are probably second generation Turnex Morellet: what is the "fastest" you can get a supernova from an early star? CT Hykova: but nothing that is a primordial star Paradise Tennant: /i've been reading . programming the universe by seth lloyd .he talks about before the big bang .. there being both an abscence of time and space.. having trouble getting my mind around it .. CT Hykova: but those will be harder to find CT Hykova: because they will be very massive timur Congrejo: did you ever see the film moonwalker? what planet is he from? Kelly Young: seems like if a primordial star was very close you couldn't find it CT Hykova: like...100x the mass of the sun CT Hykova: so they will have a very short lifetime CT Hykova: it's not clear if we will ever find one of the first stars CT Hykova: but we a looking very hard CT Hykova: with lots of big surveys Xupert Miles: Paradise: It's difficult to talk about before the big bang, since it is what is known as a "singularity" - a point where cause and effect break down. Physics doesn't say a lot about that time. Paradise Tennant: /what would finding a first star be able to tell you Turnex Morellet: ah .. do early stars not "fit" the present classification of stars .. I mean the main-series and such? Kelly Young: would they not all be collapsed objects Paradise Tennant: /i guess predates the laws of physics in a way CT Hykova: welll...if the first stars are about 100x the mass of the sun CT Hykova: they would be supergiants AdHUD v0.993: llDialog: button list too long, must be 12 or fewer entries CT Hykova: but...they would also be very different to the things we would observe Kelly Young: do stars live that long? CT Hykova: probably not Paradox Olbers: I'm curious about this q: "] Turnex Morellet: what is the "fastest" you can get a supernova from an early star?" CT Hykova: but so much is different about the first stars CT Hykova: since they have really no metals in them Barney Boomslang: so essentially you wouldh ave not only to look for a very old, but a very far away object, since the farther away, the farther back in time we "look"ß Paradox Olbers: and u said a very short lifetime for those first ones CT Hykova: so the models are not well constrained CT Hykova: welll...we would see very old stars in the milky way CT Hykova: in what we call the "halo" CT Hykova: which is a big, spherical, cloud of stars around the disk of the milkwy way CT Hykova: that is usually where we look for old stars Xupert Miles: Question for you, Dr. Thom. Can we use data from 1st and 2nd gen stars to probe early universe assymettry? CT Hykova: what do you mean by assymetry? IM: ewi Matova: can you close the SL in my office?? IM: Second Life: ewi Matova has left this session. IM: Second Life: Troy McLuhan has left this session. Kelly Young: could u maybe find early stars by seeing a gravity source without a visible star Xupert Miles: I know that background microwave radiation is used to probe the energy assymetry of the early universe. Online Tracker: Lloud Laffer, please say your message on one line and it will be recorded and/or sent. CT Hykova: no...seeing stars is easier done with light CT Hykova: the gravity methods are far too hard Xupert Miles: And that assymetry is important for star and galaxy formation (if it was a "flat", symetric start, then nothing would form). does that make sense? CT Hykova: usually they use a technique called "gravitational lensing" CT Hykova: ohhhhh. CT Hykova: so by assymetry, you mean the pertubations in the CMB -- lumps in the CMB? Xupert Miles: I.. think so. What is CMB? Turnex Morellet: how much redshift do the star have? CT Hykova: right...the CMB pertubations won't be a good way to find the first stars CT Hykova: CMB pertubations are the seed for the first stars and galaxies CT Hykova: and we could maybe use these pertubations to figure out WHEN they form CT Hykova: but we couldn't use them to see individual objects Xupert Miles: Makes sense. CT Hykova: what is the CMB? CT Hykova: well...the CMB = Cosmic Microwave Background CT Hykova: there are photons from the very early universe...it's the earliest light we see from the baby universe Xupert Miles: Ah, k :) CT Hykova: If you want to know more about the CMB CT Hykova: slacker astronomy has a podcast with Mike Turner CT Hykova: and steve meyer CT Hykova: from the Kavli institute of cosmoloigcial physics Paradox Olbers: /mg suspend Paradise Tennant: /so finding a first star would tell you more about the age of the universe ..and how it was formed ..the singularity ?? CT Hykova: yes....the first stars must obviously be younger than the universe CT Hykova: so the older the star, this gives us a limit on the age of the universe CT Hykova: and our star, is (luckily) younger than the universe by a couple hundred million year You: Here is the interview with Dr. Meyer: http://www.slackerastronomy.org/slackerpedia/index.php/Show_Notes:_Cosmology_7 Turnex Morellet: wouldn't most early stars be very far away? You: it's really fun, he tells a good story CT Hykova: so....these are two different measurements that agree with each other CT Hykova: actually some of the oldest stars are in our own galaxy CT Hykova: in what we call the halo CT Hykova: they formed very early on in the universe Turnex Morellet: oh ok .. explains why you can observe them then :) CT Hykova: and are still around CT Hykova: they formed the baby milky way Kelly Young: how old are these? Turnex Morellet: so these star must be some really slow burning stars CT Hykova: yup...these stars burn slowly and live for a very very long time CT Hykova: from the uranium in the star we found -- HE1523-0901 -- we figured out it is 13.4 billion years old CT Hykova: with an error of about 2 billion years Troy McLuhan: So that one you observed is in the Milky Way Galaxy? CT Hykova: yup CT Hykova: it's in the milky way Barney Boomslang: hm. if first stars have no metals (except maybe a little iron) - how would be the chances for one of them having planets? thinking on what the first planet in universe could theoretically be :) Turnex Morellet: you measure the strength of the Uranium line in the spectrum? CT Hykova: in the halo CT Hykova: yup...we measure the urnaium in the star we observed CT Hykova: and do a process similar to radiocarbon dating CT Hykova: only with uranium and thorium CT Hykova: and we can find the age Troy McLuhan: It would be tricky to get a sample and do mass spectrometry CT Hykova: hahahah...yeah, we couldn't really get a sample :) Paradox Olbers: :) CT Hykova: but we can get a pretty high resolution spectrum Iszy Kapuskas: =) CT Hykova: with a BIG telescope Turnex Morellet: so it is based on a model on how those two elements "spread" from generation to generation of stars? CT Hykova: we used the VLT -- very large telescope -- in chile Xupert Miles: So basically, we know how long it takes uranium and thorium to decay, we measure how much is decayed, and plug it into the radioactivity equation and get the time it took to do so? CT Hykova: yup Iszy Kapuskas: VLT - creative hehe CT Hykova: that's about right CT Hykova: yeah...not very creatively named Iszy Kapuskas: wow that's so simple really cool CT Hykova: but it IS very large CT Hykova: and it has one of the best spectrographs in the world for this work Turnex Morellet: so the elements are created in a supernova and decays in the star? CT Hykova: yes... CT Hykova: sort of CT Hykova: the big bang makes hydrogen CT Hykova: helium CT Hykova: deuterium CT Hykova: and a very little bit of lithium Paradise Tennant: /if you are measuring stars .. does anyone measure star dust .. i thought all humans had some mineral elements derived from star dust CT Hykova: everything else is made in either stars or supernova explosions CT Hykova: so....all the elements in your body CT Hykova: have once been in a star Klaatu Congrejo: how long does it take for uranium to deteriorate to unmeasurable quantities? Troy McLuhan: Everything? CT Hykova: YOU are made of star dust :) Paradise Tennant: /can those elements be quantified as to age Iszy Kapuskas: everything...the universe started as a bunch of stardust Paradise Tennant: /lololo here I feel mostly nine CT Hykova: half life = how long it takes for half the atoms to decay CT Hykova: uranium has a very long half life CT Hykova: it sticks around for a LOOONG time Kelly Young: so it takes forever CT Hykova: and this is also why nuclear waste is a problem CT Hykova: so the half life of Uranium 238 CT Hykova: is 4.5 billion years!! CT Hykova: so...even after 13.4 billion years in our star Turnex Morellet: isn't it tricky to calibrate the expected abundance of early stars? it must be different than now at least CT Hykova: we can still observe som of it Iszy Kapuskas: ayayay CT Hykova: calibrating the abundance is tricky Turnex Morellet: ups, expected abundance of uranium i mean CT Hykova: but we use a technique called spectrum synthesis CT Hykova: where we model the spectrum of the star CT Hykova: and match the model to the observed data CT Hykova: I can show you this pricutre if you're interested Turnex Morellet: but how do you know the level of uranium for the early universe? Iszy Kapuskas: i would love to see the picture CT Hykova: we will send you a link to the pdf of the paper You: You can read the abstract and download the paper PDF here: CT Hykova: and here you can see the spectrum You: http://arxiv.org/abs/astro-ph/0703414 CT Hykova: jsut click on "pdf" on the right hand side Iszy Kapuskas: awesome thanks so much =) Xupert Miles: How do we know that the decay products are not created independently of the U/Th decay? Klaatu Congrejo: so the age of deteriorated uranium is only modeled on observable data? Not actual quantified data? CT Hykova: look at the fig 2 on pg 3 CT Hykova: you can see the blue line is what we expect is there was NO uranium at all CT Hykova: and the ride lines are where there are different levels of uranium CT Hykova: nono...we actually quantify the observations CT Hykova: and then we make a model that matches our expectations CT Hykova: or our observations i mean Kelly Young: good save CT Hykova: about the decay products...we don't meaure the decay products CT Hykova: we measure how much uranium is still left CT Hykova: and we know how long uranium takes to decay CT Hykova: and we know how much there was atthe start Barney Boomslang: what from do you know how much was at the start? CT Hykova: so....if half of it decays every 4.5billion yrs Klaatu Congrejo: but Im confused, is there still any uranium left to measure after all this time? CT Hykova: yes CT Hykova: we measure that there is uranium there now CT Hykova: if you can see our pdf Xupert Miles: How do we know how much was there originally? CT Hykova: you can see this line is present CT Hykova: figure 2 CT Hykova: to get how much was there originally CT Hykova: we use the models that people have created CT Hykova: is from the uncertainty in these models CT Hykova: and the largest part of the age error Emerald Guyot: So when this star was born, what would its immediate neighborhood have looked like? Turnex Morellet: that model is calibrated after what "area" of the galaxy the star is in? CT Hykova: it's tough to know what the neighbourhood would look like Turnex Morellet: hot? :) CT Hykova: we know that most stars aren't born alone though CT Hykova: they are usually formed in multiple star systems CT Hykova: there would have been a lot of gas CT Hykova: all collapsing Emerald Guyot: Are the others gone then? CT Hykova: well...this star is in the halo CT Hykova: so probably the other stars CT Hykova: have been torn away to somewhere else Emerald Guyot: Oh! CT Hykova: as they interact with the forming milky way galaxy Kermit Halasy: Do stars ever merge? CT Hykova: this star would have formed in a tiny proto-galaxy CT Hykova: and all those proto-galaxies merge over the lifetime of the universe Xupert Miles: so sorry, SL crashed on me. Did you say how we know how much U the star started with? (apologies) Kelly Young: i can give you a chat log CT Hykova: yes CT Hykova: the initial amount of U238 is based on production models Xupert Miles: Kelly, yes please :) CT Hykova: and those models are ok, but they give us a large part of the error in our age measurement You: Ill post the transcript on the slacker astronomy web site also Emerald Guyot: How did you know where to look for this? Or did you just get lucky? Xupert Miles: Ah, I see. CT Hykova: well...to find them, it's very hard Klaatu Congrejo: How large an error are we talking about Turnex Morellet: what magnitude is this star anyway? I bet its not something we can catch in our backyard :) CT Hykova: so...this is work that my collaborator, anna frebel, is heading CT Hykova: survey almost 2000 stars CT Hykova: she started out for her thesis CT Hykova: and then doing follow-up observations of many many stars CT Hykova: i got lucky when i was observing CT Hykova: and observed this star for her CT Hykova: she was VERY excited when i sent her the data :) Emerald Guyot: Were you looking for this sort of thing specifically? Or was it serendipity? CT Hykova: actually the star is pretty bright CT Hykova: magnitude V=11.1 CT Hykova: you could see this with a biggish backyard telescope Turnex Morellet: oh thats not bad CT Hykova: we were searching for stars like this florenze Kerensky: a bbt then? CT Hykova: ones which have a very small amount of metals CT Hykova: because these are the oldest stars Barney Boomslang: lol flo florenze Kerensky: :) Paradise Tennant: /so dating stars tells us more about the age of the universe ..but not much more about how it got started.. CT Hykova: the age of the star gives a lower limit on the age of the universe CT Hykova: for a while...some stars seemed to be older than the age of the universe CT Hykova: when the age of the universe wasn't as well known Troy McLuhan: There's also something very romantic about stars that have been around almost since the beginning of time CT Hykova: and the stars ages were also not well known Klaatu Congrejo: You mentioned earlier that there was a margin of error in these age measurements. Exactly what IS that margin, 10pct, 20pct? CT Hykova: NOW...the age of the universe is very accurately known CT Hykova: from the WMAP satellite CT Hykova: it is 13.7 +/- 0.1 billion years old CT Hykova: our star is 13.4 +/- 0.8 +/- 2.2 billion years Klaatu Congrejo: Thats a pretty fine margin CT Hykova: the first error is just statistical CT Hykova: the second is the error from the models Emerald Guyot: What do you plan to do next to follow up on this research? What do you still want to know? Emerald Guyot: What do you plan to do next to follow up on this research? What do you still want to know? CT Hykova: this is a pretty accurate age for a star like this Klaatu Congrejo: Sounds like almost an exact science? CT Hykova: well...there is a lot to be know about this star CT Hykova: we will analyse all the abundances of the different elements CT Hykova: and see what that pattern tells us Turnex Morellet: can you date younger stars using this method, and if so, how much uncertainty is there from the models there? 20% like for yours? CT Hykova: astronomy is not often a "precise" science...because the measurements are so hard to make CT Hykova: dating younger stars is harder to do CT Hykova: did you see the spectrum in the pdf file we sent? CT Hykova: if you did....you can see there are other lines in the spectrum CT Hykova: and younger stars will have much stronger lines CT Hykova: ...these stronger stars just blow away the weak uranium CT Hykova: line Kermit Halasy: Those of us who are social scientists often find the lack of precision in astronomy somewhat ironic. Erszhebet Maertens: PDF? CT Hykova: hahahah...but in the social sciences you can go and inspectr the individuals Xupert Miles: How so, Kermit? CT Hykova: we can't go and inspect a star :) Troy McLuhan: PDF at http://arxiv.org/abs/astro-ph/0703414 Turnex Morellet: how about a young cool star? isame problem? CT Hykova: tnx troy CT Hykova: yup. same problem CT Hykova: check out the pdf and look at fig 2 CT Hykova: see that there is a very strong iron line in the spectrum? Kermit Halasy: We get accused of being very soft even while some are quite quantitative and can make some relatively precise measurements with high reliability. Kat Shepherd is Online CT Hykova: in young stars, there is a LOT of iron CT Hykova: so that line would totally cover the uranium signature Paradise Tennant: /what does the typical location of older stars suggest in terms of expansion ... Turnex Morellet: ah I see IM: Emerald Guyot: Thanks for hosting the lecture. Very interesting. Gotta run. Xupert Miles: Kermit, ah, that makes sense. I have a physicist friend who is stupid about not liking social science... Klaatu Congrejo: But the furthest stars are not necessarily the oldest right? Why is that? Freyr Elvehjem is Offline Turnex Morellet: what is the theoretical maximum age possible for a star observable from us with todays telescopes? CT Hykova: well....inside the milky way Troy McLuhan: Well, all distant stars are old, but the near ones are a mix right? CT Hykova: stars that are still forming, do so in the plane of the milky way CT Hykova: that is where the young stars are CT Hykova: because that is where the gas is that stars form from CT Hykova: old stars are in a halo around the disk Klaatu Congrejo: How far is the Milky Way away from the 'centre' of the known universe and how far is the Milky way from the outer edge of that known universe. Is this known? Troy McLuhan: I'm not sure it makes sense to talk about the "center" of the universe, does it? CT Hykova: there is no :"centre" of the universe Troy McLuhan: Bill O'Reilly Paradise Tennant: /outside the edge of the universe .. is what .. a zero .. .. a big empty non space ..non time thingy Klaatu Congrejo: But surely there must be a theoretical 'centre' where it is thought the Big Bang began? Paradise Tennant: /or are there really giant turtles :))) Barney Boomslang: of course. a giant turtle with four elephants on it, carrying the universe ;) CT Hykova: nonono CT Hykova: the elephants carry the planet CT Hykova: which is flat CT Hykova: and the water flows off the edge :) Erszhebet Maertens: lol Barney Boomslang: hehe Kermit Halasy: LOL Xupert Miles: The trick is, since the Big Bang happened at an infinitely small point, everything started there. All points in the current universe started there. Paradise Tennant: /:)))) Areyn Laurasia: :) Xupert Miles: Think of a balloon. Turnex Morellet: what is the theoretical max age of a star such as the one you observed? Xupert Miles: Draw some dots on an unexpanded balloon and blow it up. Xupert Miles: You'll notice that all the dots move away from each other, and you couldn't say whether one was the middle, since they are all moving away from each other. Iszy Kapuskas: because the universe is constantly expanding Klaatu Congrejo: I get that. But do we have a theory as to where this 'unexpanded balloon' point is? Iszy Kapuskas: that's a really good analogy xupert Xupert Miles: And the space itself is expanding. If the space was already there, then we could say there was a center, but since the space is being created... Paradise Tennant: /in a way because more information is being created .. it expands to hold the info .. lloyd thinks the universe is a giant quantum computer .. Troy McLuhan: Klaatu, I think every point is the unexpanded balloon point, if I followed CT Hykova: yup...the universe is still expanding Xupert Miles: that's right, Troy. CT Hykova: that was first observed back in the 20s by a guy named edwin hubble Xupert Miles: So every point in the universe is the center, the place of creation CT Hykova: who made a famous "hubble law" Kermit Halasy: How strong is the evidence that it is expanding at an accellerating rate? Paradise Tennant: /beautifuly ties into the concept that we were all one thingy at one point CT Hykova: well...the evidence is very strong for an accelerating universe CT Hykova: but we don't know what causes that, but we call it "dark energy" Xupert Miles: Yeah, isn't that cool? That and the part where we all were part of a star once... really spiritual, existential stuff there. CT Hykova: and this energy drives the accelerating expansion of the universe Kermit Halasy: The line between astronomy and metaphysics gets a little blurry doesn't it? LOL Troy McLuhan: I have an atom that says he wasn't part of a star once. Is he just deluded? Barney Boomslang: troy: either that or you work in some super-collider ;) CT Hykova: yep...this is cosmology -- the study of the nature of the universe CT Hykova: but...it's very much grounded in observations Xupert Miles: He could be a hydrogen atom, since, as CT said, that was created by the Big Bang (is that right?) CT Hykova: it is only recently that we talk about "precision cosmology" Kermit Halasy: IN another life I might have followed the route to astrophysics. Klaatu Congrejo: Do you have any thought on the 'edge' of the universe? Is there a limit? And what do you think about the theory of 'bubble universes' that we are just one bubble in a whole giant soup of bubbles? CT Hykova: with the launch of the WMAP satellite in 2001 we now have a very good idea of the parameters which describe the universe CT Hykova: they are known quite accurately Iszy Kapuskas: yeah it is beautiful that we all were stars once, and that our bodies become other things - living, nonorganic, whatever =) Turnex Morellet: do you have any model prediction of how many early generation stars that still is alive? Kermit Halasy: WMAP == http://map.gsfc.nasa.gov/ CT Hykova: stars can be a large variety of ages CT Hykova: for instance...there are still stars forming right now Turnex Morellet: I understand that many early stars were heavy so the long lived ones must have been much rarer CT Hykova: and they have been constantly forming for at least 13.4 billion years CT Hykova: so there are many different generations of stars. the age of a star is entirely dependant on it's mass CT Hykova: actually...big stars burn their gas fast -- they live fast and die young CT Hykova: so the oldest stars are also the least massive Turnex Morellet: but if we want to meausre more old stars it would be nice to know how good the odds are for finding one CT Hykova: and the way to find the oldest stars Kelly Young: but your obseved star is a super-giant? CT Hykova: is to look for things which don't have many metals CT Hykova: which is what we are doing to find these Turnex Morellet: do you have an idea if this is just a freak accident you found this star or do you suspect there are many more just as old in our galaxy? You: Hey all, we have about 5 more minutes with our guest CT Hykova: well...it's a controlled accident Xupert Miles: Well, I have to go. Thanks so much for the discussion, CT, and for hosting, Slacker, and everyone else. You: if you have any more questions please ask them now Turnex Morellet: haha ok CT Hykova: we know how to look for these things, and where the best place to look is CT Hykova: but it's still luck of the draw You: BTW, pls join the slacker astronomy group for notices of future talks Paradise Tennant: /take care xupert :) Kermit Halasy: Sounds like a carrier landing. LOL florenze Kerensky would like to say that old stars may be in the halo, but in my halo, this star isn't that old :) CT Hykova: tnx xupert Paradise Tennant: /:))) florenze Iszy Kapuskas: yes i must be off as well - you will be posting the transcript? Klaatu Congrejo: On behalf of my people I thank you Slacker. Ill take this info back to my planet for discussion. lol. You: hehe Paradise Tennant: /:)) klaatu You: yes I'll post the transcript at slackerastronomy.com, but maybe not until Saturday (I'm travelling tomorrow) Iszy Kapuskas: oh that's fine =) Xenu Carter is Online You: Also, we have a series of cosmology interviews you can download there too.. all recorded this week Paradise Tennant: /thank you slacker ..ct Kelly Young: thanks Dr. Thom, very informative & exciting Iszy Kapuskas: thank you so much =) Pinkfeather Heron: thanks to all who organized this chat. I enjoyed what I just learned. :) ciao~! Kermit Halasy: Thanks! Klaatu Congrejo: Many thanks to our guest. Bye. You: while I'm plugging things. .:) Barney Boomslang: yes, thx ct and slacker - very interesting again :) CT Hykova: no problems...thanks all for the great questions florenze Kerensky applauds Barney Boomslang applauds Areyn Laurasia claps You: We're going to have a cosmology segment in future slacker astronomy episodes, where we talk to Kavli scientists about a cosmological topic.. Paradox Olbers: thx! Troy McLuhan: Excellent You: thanks for coming! Kelly Young: byee guys Areyn Laurasia: Thanks for the talk. Kermit Halasy: Thanks you!!!! CT Hykova: thanks for making my first SL expereince fun :) florenze Kerensky: you presented nicely :) Paradise Tennant: /kk have a great night all :)))) florenze Kerensky: hope to hear you again florenze Kerensky: tc all, and thanks :) Barney Boomslang: ct: will you drop in again? or is this a one-time-gig? :) CT Hykova: sure...i can drop in on future chats You: We'd love to have him return and will plan something in the few months.. Kermit Halasy: It is this kind of talk that makes me keep on with SL. You: We tend to have them about once a month or so.. Barney Boomslang: ok, heading back to my rock here. Kermit Halasy: Thank you Slacker for organizing it. Barney Boomslang: thx again for the nice talk - enjoyed it lots! Kermit Halasy: There is no graceful way to standup in SL, is theres? Barney Boomslang: lol CT Hykova: lol florenze Kerensky: when is next chat you are hosting slacker? Barney Boomslang: yeah, it's kinda goofy. totally un-gargoylish :) Erszhebet Maertens: no graceful way to sit down and not end up someone's lap either LOL Erszhebet Maertens: Sorry Professor Erszhebet Maertens: XD Kermit Halasy: LOL! CT Hykova: cyas Erszhebet Maertens: *blushes with embarrasment* Erszhebet Maertens: Ciao You: We're open to help to make this a better place.. You: send me an IM and maybe you can help You: We gotta run now.. see you all l8r!!!! Areyn Laurasia: Bye Erszhebet Maertens: By Slacker Kermit Halasy: Dinner belll ringeth in real life. Paradox Olbers: bye!