wumpus Posted November 21, 2016 Share Posted November 21, 2016 3 hours ago, kunok said:@Nibb31 it can't be too similar to an DBV-T antenna, after all, the DBV-T is only a receptor and very directional one, the source of signal is fixed in space. An omnidirecionall antenna will be pretty big, or you will need a tracking device (a mechanical one or a phase array). The more I think the less sense it makes to me. Not for a distant future, but too early. Other problem with space networks is that almost every step you make to make the space communications affordable can be used too for the earth based one for cheaper. I really expect that space communications will decline Don't underestimate the outrageous amount of power a GPU (typically part of a phone chip) represents, I'd be surprised if you can't [physically] build a phased array into a phone. Hopefully they won't have a "you're holding it wrong" issue, the physical array will be pretty constrained. This leaves the big issue of what frequencies spacex can use: established companies will do everything to keep them off the spectrum, while such antenna wouldn't interfere with existing towers. I suspect the political/economic battle is even more difficult than building and launching thousands of satellites. The actual phone might be an afterthought (although since the physical antenna would have to be different, this painfully inflate the price of compatible phones. Again, economic issue. Link to comment Share on other sites More sharing options...
Kryten Posted November 21, 2016 Share Posted November 21, 2016 The FCC application does not mention mobile usage afaict, the only mention of antenna is as wall or roof mounted. Elon has said that the intention for the network is internet backbone, with direct consumer use as a small proportion; and at the same event opined that trying to connect direct to phones was one of Teledesic's major mistakes. He's intending to compete with fibre backbone companies, not making a super-Iridium. Link to comment Share on other sites More sharing options...
magnemoe Posted November 21, 2016 Share Posted November 21, 2016 2 hours ago, Kryten said: The FCC application does not mention mobile usage afaict, the only mention of antenna is as wall or roof mounted. Elon has said that the intention for the network is internet backbone, with direct consumer use as a small proportion; and at the same event opined that trying to connect direct to phones was one of Teledesic's major mistakes. He's intending to compete with fibre backbone companies, not making a super-Iridium. Ok, but direct consumers is an small part? I he aiming for cooperate / governmental use as I posted above, probably still smaller than lot of their stuff. Backbone makes little sense to me, yes planes or ships need an backbone connection. but else it leaves some islands and stuff who is not cabled. Link to comment Share on other sites More sharing options...
Kryten Posted November 21, 2016 Share Posted November 21, 2016 He's aiming to compete directly with fibre backbone on latency grounds. Link to comment Share on other sites More sharing options...
kunok Posted November 21, 2016 Share Posted November 21, 2016 To a backbone like @Kryten says have some sense for unpopulated isolated areas, but i don't really see that big investment. And for that wouldn't you need an ITU application? We can't forget that nowadays is somewhat common in new installations to use hybrid electric-optic fiber cable for electrical distribution, https://sc01.alicdn.com/kf/HTB1Cv9VFVXXXXbGXFXXq6xXFXXXI/202158697/HTB1Cv9VFVXXXXbGXFXXq6xXFXXXI.jpg , the hybrid cable is not much more expensive than the normal one, the bigger cost is usually the labor cost and the electric poles, not the cable itself. This alone is getting the fiber backbone bigger and bigger. And regular optic fiber is getting more and more distributed. Here we have the submarine fibber map http://www.submarinecablemap.com/ most populated islands looks like there already have fibber, and there is the public terrestrial transmission map http://www.itu.int/itu-d/tnd-map-public/. Why France, USA or Germany doesn't appear? Why this isn't a public knowledge? @wumpus I don't expect that a single element of the phase array space capable to be smaller than a regular telephone antenna, and you would need lots of them. The smartphone GPU doesn't really consume that much compared with this kind of communications. Link to comment Share on other sites More sharing options...
Northstar1989 Posted November 22, 2016 Share Posted November 22, 2016 (edited) 18 hours ago, Nibb31 said: There is a lot more in your 20€/month subscription than just network infrastructure. You need more than just a network to run a service. But we're not talking about any of that other stuff- just the comparative network costs. You can't say compate network costs to total costs, that's apples-and-oranges. 16 hours ago, Nefrums said: I think this looks very cheep for building a mobile network. I work for a Swedish network company, and we sell HW for mobile networks for around 15B$/year at 28% market share. Thou I don't see how a few thousand satellites would be able to handle the amount of data transmitted over mobile networks. Edit: The more I think about it this looks more for internet of things than for regular mobile users. Good latency and limited amount of data. The SpaceX network would cost less than $15 billion TOTAL, and would cover the entire globe. I'm pretty sure they can find a way to make a profit off that... 14 hours ago, Nibb31 said: I think the terminals are going to need too much power for IoT applications, or even for pocket-sized mobile devices. Remember the closest sat will be 1000km away. I think it will be fixed subscriber boxes with something like a DVB-T antenna. The nearest satellite will NOT be 1000 km away. This is a Low Earth Orbit constellation, which means the satellites only orbit 400 or 500 km up. And the shear number of satellites is so great lateral distance should NEVER double total distance. That would require the satellite was at less than a 26.56 degree angle to the horizon. 12 hours ago, Nibb31 said: By definition, low population areas only cover a small population, which makes it a niche market. If there are any drawbacks to it (price, terminal size, capabilities, data limits, etc...) it will remain in the niche, just like Iridium. As long as we don't have that marketing data, it's impossible to predict whether it will succeed or fail. Musk has a tradition of disregarding marketing realities. He has his own reality distortion field. In some cases it works, in most others it doesn't. Neither Tesla, not SolarCity have ever reported any profits. SpaceX was profitable for the first time in 2015, but depending how much it gets sidetracked by Musk's Mars hobby, and the impact AMOS-6 had on the schedule, that might not repeat in 2016. Low population-density does not mean low TOTAL population. Rural areas may have fewer people per square kilometer, but COLLECTIVELY they contain a very large population as more than 90% of the planet is rural. Musk has been VERY aggressive at *GROWING* his corporations. Necessarily, this means lots of investment in new infrastructure and low net cashflow. But EXISTING, ESTABLISHED infrastructure in Musk's corporations has proven itself HIGHLY profitable- the problem is just that Musk keeps going and re-investing all the net revenue in new projects and infrastructure instead of passing it along to shareholders. Eventually, Musk will run out of profitable new projects to invest in, and either stop re-investing or start investing in projects that DON'T turn a profit... Maybe not the best companies to invest in if you're looking to make a quick buck (like so many Americans are obsessed with- we as a country don't know how to deal with delayed gratification), but aggressive growth is a sound strategy in the medium term. There's a reason that banks and shareholders continue to consider Musk corporations a sound investment, and it's not because these financial experts who have spent decades investing are somehow dupes who have all drunk the Kool-Aid like you seem to think, Nibb. Edited November 22, 2016 by Red Iron Crown Link to comment Share on other sites More sharing options...
YNM Posted November 22, 2016 Share Posted November 22, 2016 (edited) On 11/21/2016 at 9:39 AM, Northstar1989 said: Did you pay any attention to the numbers I put forward earlier? I used a baseline of 20 Euros/month for service and showed that it indicated a much higher infrastructure cost relative to service area than the SpaceX satellite constellation plan. If imfrastructure costs were just 1 Euro a month per person, and the rest were all profit, Musk's satellite constellation would still be a much cheaper option than ground-based infrastructure for just the USA, Japan, Canada, Australia, and Europe- and that's completely ignoring the developing nations of the world... Putting satellites up doesn't mean no infrastructure costs - you need ground satellite controls and proper local ground repeater (I will shout "No" if you're proposing direct transmission of mobile data, all the bands are close to IR microwave and it'll be thousand of km away still). Also, don't forget development cost - the only prominent cost today, AFAIK, are development costs. Ground cables are relaid while satellites needs to be re-launched. I'm not sure which is cheaper, but certainly you can't go up and upgrade all the sats to afford more bandwidth. And to be clear, I live in a part of the developing nation. We know what's happening - all provider are creating new local repeater (new ones are short but very numerous). SpaceX would need to ask for permission to use them or make new ones in any way. EDIT : Most developing nations are densely populated. EDIT 2 : Corrected a few thing, sorry. Edited November 25, 2016 by YNM Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted December 2, 2016 Share Posted December 2, 2016 RTF is apparently on for December 16! http://investor.iridium.com/releasedetail.cfm?ReleaseID=1001684 Link to comment Share on other sites More sharing options...
Rakaydos Posted December 2, 2016 Share Posted December 2, 2016 Lol... Damn lawyers... "Forward-looking statements can be identified by the words "anticipates," "may," "can," "believes," "expects," "projects," "intends," "likely," "will," "to be" and other expressions that are predictions or indicate future events, trends or prospects. These forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause the actual results, performance or achievements of Iridium to differ materially from any future results, performance or achievements expressed or implied by such forward-looking statements. " Link to comment Share on other sites More sharing options...
Aethon Posted December 2, 2016 Author Share Posted December 2, 2016 https://www.nasa.gov/feature/nasa-s-first-flight-with-crew-will-mark-important-step-on-journey-to-mars Link to comment Share on other sites More sharing options...
tater Posted December 2, 2016 Share Posted December 2, 2016 Why does NASA keep up with this "journey to Mars BS WRT Orion? Unless their free return EDL is identical to Mars return EDL, ti tells them only that Orion is fine for a direct EDL from the Moon. Orion is just a taxi to get to a real spacecraft if Mars is the goal, nothing more. Link to comment Share on other sites More sharing options...
tater Posted December 2, 2016 Share Posted December 2, 2016 Realistically Orion is going back to its roots in the next 4 years. SLS is as safe as any NASA program can be, but I bet ARM gets axed, and they need to go someplace. Link to comment Share on other sites More sharing options...
_Augustus_ Posted December 2, 2016 Share Posted December 2, 2016 1 hour ago, tater said: Realistically Orion is going back to its roots in the next 4 years. SLS is as safe as any NASA program can be, but I bet ARM gets axed, and they need to go someplace. The new administration is going to pour funds into it so EM-2 happens as originally planned in 2021, and then we'll probably see a new Constellation-style program with lunar landings (maybe Russia will provide the lander) and maybe a cislunar station too. Link to comment Share on other sites More sharing options...
kunok Posted December 2, 2016 Share Posted December 2, 2016 10 minutes ago, _Augustus_ said: The new administration is going to pour funds into it so EM-2 happens as originally planned in 2021, and then we'll probably see a new Constellation-style program with lunar landings (maybe Russia will provide the lander) and maybe a cislunar station too. Source? Link to comment Share on other sites More sharing options...
YNM Posted December 3, 2016 Share Posted December 3, 2016 58 minutes ago, kunok said: 1 hour ago, _Augustus_ said: The new administration is going to pour funds into it so EM-2 happens as originally planned in 2021, and then we'll probably see a new Constellation-style program with lunar landings (maybe Russia will provide the lander) and maybe a cislunar station too. Source? Maybe to keep people unaware that Earth Science has just halted off ? Link to comment Share on other sites More sharing options...
StrandedonEarth Posted December 3, 2016 Share Posted December 3, 2016 (edited) This article offers a little more info on the anomaly. Quote The oxygen likely froze solid and caused a high-pressure helium tank to burst, blowing the upper stage apart almost instantly, and leading the rest of the rocket to collapse in a fireball. The helium is used to pressurize the second stage’s propellant tanks for flight. Musk said engineers believe they can fix the problem with a change in fueling procedures, avoiding major hardware changes that would have kept SpaceX missions grounded longer. Glad to see that they're getting back to launching, if the FAA approves. Edited December 3, 2016 by StrandedonEarth Link to comment Share on other sites More sharing options...
YNM Posted December 3, 2016 Share Posted December 3, 2016 1 minute ago, StrandedonEarth said: ... Musk said engineers believe they can fix the problem with a change in fueling procedures, avoiding major hardware changes that would have kept SpaceX missions grounded longer. Yet-another-Challenger impending ? Link to comment Share on other sites More sharing options...
tater Posted December 3, 2016 Share Posted December 3, 2016 Earth science is 2 billion a year. Wrong planet to send spacecraft to, imo. Link to comment Share on other sites More sharing options...
YNM Posted December 3, 2016 Share Posted December 3, 2016 I wish there was some joke in it... Link to comment Share on other sites More sharing options...
tater Posted December 3, 2016 Share Posted December 3, 2016 (edited) 4 hours ago, YNM said: I wish there was some joke in it... ? I'm singularly uninteresting in blowing a substantial % of NASA's budget---indeed the vast majority of the NASA science budget---looking at Earth. I'd spend every penny of that 2 billion looking elsewhere. All of it. As von Braun once said about the V2 (paraphrasing here), it was a fine rocket, it just landed on the wrong planet. Given limited NASA resources, I want to see planets I cannot see by walking outside. NOAA can look at the Earth, that's their job. Edited December 3, 2016 by tater Link to comment Share on other sites More sharing options...
Nibb31 Posted December 3, 2016 Share Posted December 3, 2016 1 hour ago, tater said: ? I'm singularly uninteresting in blowing a substantial % of NASA's budget---indeed the vast majority of the NASA science budget---looking at Earth. I'd spend every penny of that 2 billion looking elsewhere. All of it. As von Braun once said about the V2 (paraphrasing here), it was a fine rocket, it just landed on the wrong planet. Given limited NASA resources, I want to see planets I cannot see by walking outside. NOAA can look at the Earth, that's their job. Some would argue that NOAA's budget is just as important as NASA's, so if NASA no longer gets to do Earth observation, then the budget that was used by NASA for that purpose should be transferred to NOAA, otherwise, you reduce America's earth observation capability, which would be a reckless thing to do with everything that's going on. Link to comment Share on other sites More sharing options...
tater Posted December 3, 2016 Share Posted December 3, 2016 (edited) 4 minutes ago, Nibb31 said: Some would argue that NOAA's budget is just as important as NASA's, so if NASA no longer gets to do Earth observation, then the budget that was used by NASA for that purpose should be transferred to NOAA, otherwise, you reduce America's earth observation capability, which would be a reckless thing to do with everything that's going on. If you find it reckless, perhaps ESA can pony up for it, NOAA/NASA is not just observing the US, after all. I'd personally suggest looking more at the sun. Edited December 3, 2016 by tater Link to comment Share on other sites More sharing options...
Nibb31 Posted December 3, 2016 Share Posted December 3, 2016 (edited) 19 minutes ago, tater said: If you find it reckless, perhaps ESA can pony up for it, NOAA/NASA is not just observing the US, after all. ESA actually does. So do many other research organizations around the world. Climate deniers can deny the causes, but it's undeniable that stuff is happening and that we need to better understand exactly what is and why. To stop measuring the problem won't make it go away. Proposing cutting science budgets, just because you disagree with the results, is obscurantist, and we have enough of that already. Quote I'd personally suggest looking more at the sun. Yes, they do that too. Ever heard of SOHO ? And ESA Solar Orbiter is scheduled for launch in 2018. Edited December 3, 2016 by Nibb31 Link to comment Share on other sites More sharing options...
Jonfliesgoats Posted December 3, 2016 Share Posted December 3, 2016 8 hours ago, YNM said: Yet-another-Challenger impending ? Spaceflight is inherently risky. Developing a system, that can sustain a high op tempo means taking on some of these risks. Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted December 3, 2016 Share Posted December 3, 2016 So I'm seeing SpaceX catch a lot of flak from armchair rocket scientists for not having unequivocally, absolutely nailed down the cause of the problem. Under the circumstances, is it even possible to do so? Link to comment Share on other sites More sharing options...
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