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    Bye bye Cassini.

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      The video is worth watching. I was having a look at a gallery the Graundiad did of selected images from the 14 years and it's just amazing. https://www.theguardian.com/science/...gapixel-camera

      So which planet are they visiting next?

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        Sniff. Farewell Cassini, indeed.
        https://twitter.com/neiltyson/status/908508645247344640

        Apart from the amazing official images released, it's worth noting that NASA also make all of their raw data from the mission freely available to anyone, with some astonishing results: this picture of Saturn for instance was made by an amateur. This unofficial, eerily beautiful video of raw data from Cassini’s cameras meanwhile is like some extraordinary time capsule – the flickering, grainy, too-fast monochrome footage gives it the dislocating air of having been 'filmed' a century or so ago, as if the Victorians had casually flung a rocket with a cinematograph toward Saturn in 1897 instead of NASA launching a space probe in 1997.

        And aside from everything else, Cassini gave us ourselves, from a billion miles' distance:
        https://twitter.com/neiltyson/status/908453304342073345
        Last edited by Various Artist; 15-09-2017, 23:38.

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          Awesome.

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            So Vice President Pence made his big announcement, and America is going to be made great by going to the moon, at some unspecified point, and future administrations are going to pay for it!!!!!. Now to a certain extent this is what every administration does. At the end of Apollo, everyone came to a huge realization. NASA had made enormous strides in space flight, in an absurdly short time, but at enormous expense, and require a substantial national effort akin to building the pyramids. But ultimately, all they could do was land 5 tonnes of payload on the moon, which is basically useless for anything other than planting a flag, collecting a rock or two, playing some golf, or a bit of ATVing. And every time you did this, you had to build a saturn V and throw it in the sea. Anything beyond this required a leap in technology so immense, and an investment in technology so overwhelming that everyone decided to leave well alone.

            So after Nixon left Nasa with the shuttle, carter and reagan got that going, and everyone was happy enough. Reagan started talking about a space Station Freedom, Bush decided it was long enough after apollo to risk talking about a trip to mars, but with a nice 30 year time line so you could get all the PR credit now, and it was entirely up to everyone else to pay for the damn thing. Congress killed that, and clinton sneakily tied the US into all sorts of treaties around the ISS so congress couldn't ever just kill it for the sake of it. George Bush Junior wanted to go to the moon in 30 years, and they immediately asked boeing and lockheed martin to build a terrible, underpowered rocket, and an awful pointless capsule. That didn't get very far before Obama killed it, and said "We're going to Mars Baby, and an asteroid." Congress said not any time soon, and in return for building a giant Saturn V rocket out of shuttle parts, they allowed Nasa have that contract that essentially created Space-X.

            well we got no nearer getting to Mars under Obama's presidential policy, and if obama said up, trump would say down anyway, so now trump is going to the moon, and they're trying to do the usual thing of trying to milk the credit for it etc. This is a stunt that can work as long as there are insurmountable problems in getting to the moon, or mars. But what if some day, someone came along with a means of getting to these places. What would happen then? What if it was relatively easy and cheap to carry large payloads to the surface of the moon. Large construction robots, habitation modules, you know, as much stuff as you needed to build a large moon base. What happens then? Because that might happen a lot sooner than most people think. because there was a second announcement recently.

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              So these neutron stars producing and spewing out gold, then. How does (did) it end up on Earth? Wouldn't heavy elements from distant stars burn up in our atmosphere when they reached us?

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                The harder bit would be them tunnelling underground once they got here.

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                  In reality this stuff is spewed out of these star collisions and hangs about in space along with all the other stuff ejected.
                  this stuff over time gets mixed up with gas and dust clouds which then start to accrete (helped by the shockwave from the collision pushing it together.)
                  Eventually the gas forms a star and a accretion disk containing dust, rock, heavy elements etc. Then the planets form with the heavy elements in the mix. Settling due to heat\liquidity etc. tends to leave layers of different elements in different places within the planet.

                  So long story short, the gold was here when the planet formed, same as all the other stuff. The solar system was formed from the remains of one or many supernovae and apparently neutron star novae.
                  Although I think they should have sunk to the core if they were here when the earth formed.


                  Of course at one time the Earth didn't have an atmosphere, so any asteroids that contained these elements could hit without burning up, so it's possible more of these elements were dumped post formation.


                  The bigger the clump, the less likely they are to burn up in the atmosphere - look at meteorites. So even after the atmosphere formed (relatively recently) they can still get to Earth.

                  The Earth is really dynamic, so what's on the surface could easily have been underground fairly recently and vice versa.

                  Of course, this is why it's worth going to see what can be mined from the asteroid belt. There are rocks out there containing all sorts of good stuff. Basically anything we can find on Earth, should be out there in abundance.
                  Last edited by hobbes; 17-10-2017, 08:20.

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                    I thought that it was down to huge golden meteorites slamming into the earth a long time ago. That seems a little crazy in hindsight. But then again we've just seen two stars crash into each other.
                    '

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                      Even if the asteroids "burn up" in atmosphere, any gold would still mostly stay on Earth. It's not hydrogen or helium.

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                        There's not very much gold is there? The total volume that we've mined apparently would make a cube with a 20m side. For some reason that doesn't seem like very much. There's about 150,000 tonnes of the stuff knocking about, and they estimate another 50,000 tonnes or so in mines. Is there a lot more of the stuff further down?

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                          LEGO news.

                          Following on from the stunning Apollo set (which I'm still so tempted by) LEGO have just announced.

                          Women of NASA

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                            I like Nancy Roman's pearls.

                            I do wonder if they should've included Judith Resnik and Christa McAuliffe.

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                              And Carolyn Porco.
                              Oh and the Saturn V set is bloody brilliant, Levin.

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                                Eileen Collins was the first woman to fly the shuttle, and the first woman to command the shuttle. She was the commander as well on the first mission after columbia. both her parents were from cork, but I was completely unaware of her until she spoke at the RNC, in a rather ill advised move. by contrast chris hadfield is a celebrity here, and was on a chat show at the weekend. I find that rather strange. She should have been a lot more famous here. Maybe she should have sent her daughter to college in dublin, and gone on twitter more often.

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                                  Oh and looking back, I seem to have forgotten about the second major announcement of the last six months, one that is considerably more important than whatever nonsense Mike Pence was talking about. Space-X gave their annual update on their plan to go to mars. Last year musk joked about the Underpants gnome nature of the first announcement. in that there was no real idea for how anyone was going to pay for the development of this thing, so ultimately the whole thing wound up looking like a richard branson fever dream, with all the richard branson brand advertising removed. This was very different.

                                  Musk is technically speaking, a terrible public speaker, and he is also constrained by not wishing to piss off his two main customers, who are NASA and Communication Satellite companies, while simultaneously trying to get people behind the idea of going to Mars, so consequently it's necessary to put a bit of structure on what he was saying. But the key elements of it were

                                  1. Space-X is heading for a near total global monopoly on commercial satellite launches as early as next year. They have their ISS contract, and they are winning more and more DOD and Air Force contracts. They will have a lot of money as these things go.

                                  2. Space-X are nearly finished with all development work on their falcon 9 and dragon series. Because they're resusable, they don't need to make too many of them to handle the next 10 years of launches. They have thousands of employees that will have literally nothing else to do.

                                  3. The only likely medium term opportunity for Growth on the horizon for a company whose business is launching shit into space, are the three consortia trying to build LEO internet satellite constellations, ranging from 800, to 4425 small satellites. (Space-X are one of these consortia) and the Falcon 9 can only launch 10-25 of these at a time. It would take forever, and cost a fucking fortune to launch these constellations. Space-x need a new rocket to meet this demand.

                                  4. So they're going to use the money they make from launching satellites, (and whatever development funding they can knock out of an enthusiastic USAF) and all their engineers, to go through the whole development process they went through with the Falcon 9, but with a more powerful engine. So the plan is they're going to build a falcon 9 as big as the Saturn V, and they're going to stick a cargo shuttle on top, that can fly up into space, open a door, and spit out hundreds of these satellites at a time. before aerobraking on its heatshield, and landing like a falcon 9. This alone is sufficient commercial reason to build this thing, even if it is never used to go to mars. This is why this is probably going to happen. There is a lot of money to be made if you build this thing, that has literally nothing to do with Mars, or the moon, or NASA.

                                  5. Since most of the Falcon 9's loads are all going to broadly speaking the same place (GEO) you can put a bunch of them in the cargo bay, and send them off together, and offer a discount, so they can eventually get rid of the falcon 9. A huge Cargo bay, and wide diameter, would make it childishly easy and cheap to launch an 8 metre space telescope, that would make hubble look like a magnifying glass. It would enable you to launch absolutely massive inflatable space station components, which would allow Science stations, space-hotels, and orbital manufacturing. it would allow you bring things back from these orbital manufacturing stations. But those are all potential future uses. It's the internet satellites that are the important thing.

                                  6. This system is considerably smaller than the one announced last year, this has two important effects.
                                  a) the engine doesn't need to be as powerful to make this whole thing work. They've been working on this engine since 2012 with some financial assistance from the US Air force. it's a 60 year old idea, that no-one ever really built, apart from one or two test engines. It allows you operate at incredibly high pressures and temperatures, which makes the engine very efficient, and very powerful. At the last announcement they showed a video of a low temperature, low pressure, 1/3rd power prototype blasting away happily on the test stand. The Aim was to gradually increase the pressures and temperatures until it was eventually 200% more powerful. Because they've reduced the size of the rocket, it only needs to be 70% more powerful, and based on the enormous number of test firings they have had, and that they have finished testing, they've probably already got there. A prototype of this engine was supposed to be launching on a second stage, as part of an airforce contract in june 2018. There is a very real chance that it will actually be essentially the finished engine needed to build this thing. That is a huge milestone for something like this.

                                  b) the tanks can be smaller, and therefore easier to build. Back in 2016 they showed a fucking enormous 12m tank. This year they showed a video of them blowing it up by pressurizing it well beyond the requirements they needed. If you can construct a 12 metre carbon fibre tank, then a 9 metre tank is going to be relatively straight forward by comparison.

                                  7, They've ordered the machines they're going to need, and are building a huge new sea front factory. And they're going to start building this first of these things next year. Whether it works or not, is another matter, but this is definitely happening.

                                  So far this has been "Space-delivery company plans bigger space-truck" because basically that's what it is. And if you think about it like that, then it makes sense, and seems plausible. At some point in the next little while Space-X are going to build this thing because it will make them a lot of money. But if it can land like this on earth, then with a spot of orbital refuelling the same shuttle can land on the moon and come back, or land on mars and manufacture its own fuel.

                                  And this brings me back to the Mike Pence announcement of the moon within 30 years. that's all going to have to stop. Politicians aren't going to be able to hide behind 30 year plans to go to the moon, if Space-X are offering fixed price Deliveries of 50 tonnes + passengers to your location of choosing, at your time of choosing on the surface of the moon. When push comes to shove, are the US govt, or the human species as a whole going to actually go to the moon? Not being able to get there was a great excuse. The best excuse ever. But that excuse may be suddenly about to disappear.

                                  Hopefully Elon Musk can take some time off whatever he's doing to get a grip of A disturbing string of stories coming out of Tesla. this is the latest installment

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                                    TAB may be interested in the documentary tonight on the Birr telescope on RTE One, also the film The Farthest was a most enjoyable recent film on the Voyager probes:

                                    https://m.youtube.com/watch?v=g-36-7jeEng

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                                      Ooooh thanks for reminding me.

                                      Btw, have you watched past the third second of that youtube video?

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                                        Originally posted by The Awesome Berbaslug!!! View Post
                                        Ooooh thanks for reminding me.

                                        Btw, have you watched past the third second of that youtube video?
                                        No, because I saw it last month, but given it says 1:58:00, just presumed it was the full film.

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                                          That was very enjoyable. I liked the visual representation of the size of the single radio dish that they'd need to achieve the same effect as all those various little installations. Do Seti get dragged into these programmes just because?

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                                            Saw the ISS pass overhead on its 17:05 transit.

                                            Currently "very bright" Geminids being reported.

                                            Watch the skies, people!

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                                              Everybody relax, Space Teddy is safe and well.

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                                                I'm glad to see that Spess Tiddy made it back.

                                                that Mahia Peninsula Rocket launch site has to be the most spectacular setting for this sort of thing going.





                                                It's basically got the temperature and rainfall of Galway, with three times as much sun. It beats the bollocks off hanging around baikonour.

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                                                  I posted this pic on the Mundane Thread yesterday, but it probably really belongs in here. I took it at the Mormon temple in La Jolla because I was out admiring their excellent Christmas Lights.



                                                  At the time I saw it, I had no idea what it was. It looked utterly freaky, and as if the aliens were invading. Or it was a gimmick by someone at Christmas trying to put a "star" above a church.

                                                  The actual explanation, though is pretty cool. It's a SpaceX Falcon 9 delivering an Iridium satellite in to low earth orbit. The thing about Iridium satellites (or, at least, this one) is that they go into polar orbits rather than the usual geostationary or near equatorial orbits. And that means that the rocket takes off something close to due south. If you want to do that, you actually want to be launching where there's no populated land south of you. Normal rocket launches from Canaveral basically head out due east over ocean, but if you head south from Canaveral you're heading over the whole of highly populated southern Florida.

                                                  Which means that they launch these rockets from Vandenberg AFB near Santa Maria, just by Point Conception in California. There is literally no land south of there until the Antarctic.

                                                  Which means that the rocket traverses the Southern California sky heading south (rather than the usual "away" that people see in Florida), so we see it for a long time, and get to see the profiles of what's going on. And it comes across the view of a huge number of people in LA, San Diego and Tijuana (and all the way east to Arizona)

                                                  But what was really special about this one that it was in deep twilight. The sun is some way below the horizon and the sky is pretty close to dark. But the rocket is up at close to 100 miles, which means that everything is illuminated in the high atmosphere. The trails of this rocket are basically the same as noctilucent clouds, and, just like noctilucent clouds, they seem totally alien and people can easily think they are an alien invasion.

                                                  At the time, it looked as if the entire trail behind the (what we now know to be a) rocket was illuminated by a massive light behind it. It really did look like a stunt.

                                                  In the pic, what you can see are - at the front - the pressure wave; then the glowing bit in the middle is, I'm pretty sure, the ejected first stage, which we then saw spin off the trajectory and begin to glow and burn up; and at the right of pic is the end of the main engine burn (I think the bigger puff is the ejection of the first stage).

                                                  Like an idiot, when people who were around me said that it might be SpaceX, I told them they were wrong, because the SpaceX Falcon Heavy is the one that all the press has been about, because it's the first launch and it's got a Tesla Roadster inside it, and that is on the launchpad at Canaveral right now. I was, of course, both right and wrong, because it didn't occur to me that SpaceX is so busy that they've got two rockets on the go at the same time....

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