I've heard that eventually most GPS devices, like phones, will be able to also use Galileo and GLONASS (the Russian satellite navigation system). Does anyone know the status of that? There's a list on Wikipedia of GLONASS-compatible phones, but it's not clear if the typical American phone can actually use it.
Also, does anyone know how much more accurate the positioning will be with the 3 systems combined? And whether phones will have access to regional systems like for Japan? The Wikipedia pages are enticing on these ideas, but I haven't seen most of it updated in a while.
Multiple band GNSS chipsets have just recently become more common. The GLONASS constellation was inactive for quite some time due to economic issues in Russia, probably the reason it's seen slow adoption. Galileo is the only other GNSS system, but it's incomplete. Then there is the issue of different bands, and need for more complex antennas and LNAs. Most of the numbers I've seen for chipsets indicate that GLONASS support is still relatively unoptimized, power consumption for GLONASS acquistion is far higher than for GPS, but I'm not sure if that's simply a poor front end for the GLONASS frequencies, or if the signal/processing is significantly different.
Beidou (China), QZSS (Japan/Australia) and IRNASS (India) are all regional systems with far smaller systems (3+ satellites), and in the case of IRNASS and QZSS, heavily augmented by ground based stations (). Development of low cost RTK (real time kinematics), giving centimeter precision in some cases, has really been driven on a large scale by the Japanese. There is some great reading (and heavy math) on the RTKLIB site, http://www.rtklib.com/rtklib_document.htm, not only about RTK, but GNSS in general.
And things are going to get even more interesting with the data from the GRACE satellites, their gravity model will help improve position accuracy even further.
Oops, I misspoke. Both Galileo and Beidou are GNSS, but both are incomplete, and are expected to be fully populated sometime 2020+. China has had a regional system up for sometime (Beidou-1), but I didn't know they've been planning and launching a second, global system (Beidou-2).
> To improve development of the user segment, on August 11, 2010, Sergei Ivanov announced a plan to introduce a 25% import duty on all GPS-capable devices, including mobile phones, unless they are compatible with GLONASS. As well, the government is planning to force all car manufacturers in Russia to make cars with GLONASS starting from 2011. This will affect all car makers, including foreign brands like Ford and Toyota, which have car assembly facilities in Russia.[15]
Since the USA owns GPS they could turn it off whenever they feel the need to sanction Russia, therefore they have created their own infrastructure.
And yes, this is also relevant for the military, Russia needs the ability to strike any adversary if they have to, as does the US and China.
No block is going to lower their guard (I'm not so sure, that the US wouldn't strike Russia right now if they could without being punished), so everyone is going to race to a first strike potential where they can't be punished by an adversary.
Once that point is reached by any side, nobody knows what will happen, which is obviously the reason, why Russia resisted the US missile defense in Poland.
We couldn't even tell what would happen, if all sides had friendly relations to each other. Someone will have the upper hand, therefore someone could be submitted. And I'm sure that none of those countries mentioned would accept submission.
I really don't think it's misplaced paranoia. Assume, hypothetically, that the Ukraine becomes a NATO member (they applied I heard) and that an attack on one triggers an attack on all and that it triggers world war three (I said hypothetical, right?), then I don't think America is going to let the Russians use GPS anymore.
And if it so happened that Europe decided that the Iraq and other middle east wars were kind of pointless and that Iran has not been developing nukes like America said they were over and over, and it ends up in war, I really doubt that we (Europeans) will get to share either the American's system.
World wars are maybe not that likely, I'm no expert, but in the case of some big war anywhere, I think the Americans would not hesitate to disable the public signal (there is already an encrypted GPS signal which is much more accurate) for a month or two and win the war because nobody can orient themselves anymore. Having a couple of system kind of makes sense.
Paranoia about being denied any use of GPS. The US could arbitrarily shut down GPS over any territory they want, pretty much fucking up the everyday life there, given how more and more things depend on GPS signals nowdays. They did this before, and though they say they won't do this again [0], the fact remains that they can, and that's good enough reason for others to deploy a system of their own.
Japan is covered by a single orbit and there system provides significantly higher accuracy (cm vs meter) than GPS so for the fairly low price tag for seven satilites it's probably worth it.
The 5 degree inclination change would likely burn through most, if not all, of the maneuvering fuel onboard the satellites. That's not accounting for the peri/apoapsis adjustments.
If they do get them to a usable orbit, they won't have enough fuel to last long.
In low orbit, sure, but if you're coming from outside the SOI, you can burn retrograde at periapsis just enough to be captured, then make a very inexpensive inclination change at apoapsis (my usual procedure for deploying a kethane scanner).
Yeah, that's a good trick - I was thinking specifically of the benefits of launching into an inclined orbit vs. the incredibly painful process of gravity turn, circularize, change inclination, and circularize again...
AFAIK, it was already established they do not have enough fuel to circularize the orbit at the correct altitude, let alone correct the inclination (which takes large amounts of fuel).
And refueling is not an option? There are also people on the ISS for example, when the crew refreshes they could do that "on the way there"... yeah I don't know anything about space, just an idea.
No, for two existing reasons; the satellite has no capability for on orbit refueling, there is no rocket available to do that.
In this situation, an on-orbit refueling capability and a tug, a ship which can pick things up and change their orbit, and refuel itself would be worth the cost of these satellites because it would take currently unusable satellites and turn them into usable ones. Not clear what the salvage rights in space are yet.
United Launch Associates (ULA) has some great work they have done on making a practical on-orbit refuelling capability but nobody has stepped up to pay for it. This is something I am hoping SpaceX will do. Elon is the type of person who might fund that on the expectation of making back the investment in saving satellites. [1]
[1] I would charge the satellite insurer 1/2 the value of the satellite to put it into its proper orbit. Which saves the insurer from paying out the full amount.
I hope someone will do that. One could imagine such satellite-recovery company to bundle several repair operations together, to minimize fuel costs of repeat orbit changes.
How? Space is not like driving a car. To go higher you've got to burn fuel to gain velocity and altitude, do go lower you've got to burn fuel to slow down. If you're going the wrong direction or angle, you've got to burn a ton of fuel to change that (i.e. if at 90deg to ISS, you've got no velocity vector in common). And that's just my armchair assessment that ignores the myriad complications of spaceflight.
This is a common misconception, however. For example, people want to know why Columbia didn't just buzz over and hook up with the ISS rather than burning up. They were at a different altitude from ISS and could not have made the jump with available fuel.
Isn't it? You drive, you burn fuel. You take more fuel with you, it costs more fuel to get going. Some vehicles (spacecraft or car) require more fuel to drive the same distance than others.
Sure, space flights are much, much more expensive, but I don't see how it's so different. If it's not worth it to spend the extra fuel to get there, refuel, and continue to the original destination, then just say so.
Conversely this is why space mining is kind of a big deal. If we could get large quantities of pretty much anything that works as a propellant without launch costs, that would change a lot of things.
Even aluminum mined on the moon would be potentially useful.
And due to the oddities of space travel, it costs a lot less delta-v to go from the Moon to Earth orbit than it does from Earth to Earth orbit, especially if you do aerobraking.
- There is no way for the satellites to reach the ISS
- There is no way for the ISS or the crew to reach the satellites
- The ISS does not carry equipment to refuel satellites
- The satellites are not equiped to be refueled in space
Wait, I saw this movie called "Gravity" where the heroine used a fire extinguisher to propel herself through space and went all over the place. It was easy. Maybe the ISS folks should try that to get the the satellites! ;-)
This thread is exactly why I called BS early and often on Gravity, despite being downvoted in numerous places for doing so and being told "It's just a movie, lighten up." A movie that leaves everyone who sees it a little bit dumber.
Yes, it was "just a movie," but you know what? Reality is pretty goddamned interesting, too. Hollywood should try it sometime.
Sure, but the thing is, Gravity was like five orders of magnitude less dumb than anything else about space. Despite all my undying love to that show, you'll not get any smarter if you watch Star Trek instead. Gravity is probably the closest Hollywood ever got to the real deal.
Still, we should learn to appreciate a thing that's better than everything even if it's still bad, instead of dismissing as not perfect. Incremental improvements, things like that...
Read the comment I replied to. I'm pretty sure s/he was being sarcastic, but I'm also pretty sure a lot of kids now think of a fire extinguisher as a useful tool for navigation in gravity wells.
I think in order to perform a refueling you would have to match orbits first. Given the expense of getting the necessary fuel up there (even if ISS uses fuel on-hand, it would have to be replenished at expense), matching orbits, and correcting the orbits, it would probably be easier to just launch new satellites.
Many orders of magnitude easier... The amount of energy required to get the ISS to same inclination and orbit as these stranded sats would be stupendous... _Well_ beyond its capabilities.
That is plain impossible. To change the shape or the inclination of the orbit takes a lot of fuel (change of 1km/s is a good order of order of magnitude even if it is more of an upper bound).
Moreover, if you have to carry fuel for somebody else it gets that much harder to accelerate/decelerate like that.
Hypothetically, rather than trying to refuel the satellite, what if something were launched as a "tug" to push/pull the satellite into orbit? I'm sure there's no time to design something like that, but maybe someday something like that will exist to correct orbits.
KSP is really really good for this stuff. I never really grokked orbital mechanics till I played it, but a lot of the weirdness of how space missions are designed makes perfect sense once you have an actual feel for how orbits react to velocity changes.
I wrote a small 2D game once, where the Earth is attacked by a swarm of satellites in polar orbits. Your ship is launched from the surface, but after that it's up to you to put yourself in orbit, using thrusters. Thinks Asteroids with gravity. It really taught me a lot about how an orbit's shape changes when thrust is applied in different directions, at different points in an orbit. For example, a good way to circularise an orbit from an elliptical, a small tangential thrust at apogee during each orbit would eventually place the spacecraft in a circular orbit with a radius roughly equal to the apogee distance of the elliptical orbit... or to say it another way, perigee would increase until it equalled apogee...
Anyway, the point being that I never would have understood any of this no matter how many times I read 2010, until I wrote that little game. Some things need to be experienced to really grok.
Orbiter too. It's incredibly difficult to make your orbit. You really have to get it right from the get go on the ground. If you have to do an orbit transfer, that can sometimes be a huge amount of your fuel just to line up for the transfer before even breaking orbit.
I gained a true appreciation for difficulty of the kind of maneuvers that are common place in science fiction after spending time with Orbiter.
Yes, Orbiter was great. It's sad that it's not really developed anymore. For those who don't know, it's like Kerbal Space Program, but using real ships and without Kerbals. It gave this distinct feeling of "the real deal" when you played it.
I remember my friend telling me he actually googled down some US Space Shuttle maunals and used the real checklists when launching in the game.
Also, Osmos is a good game to develop an orbital intuition. Oversimplified but easy to approach. There is a deviously difficult level toward the end where they give you just enough fuel to compute the level... Unless you keep your delta-V super low, you lose. Like real life.
Since I cannot edit this post anymore I'll comment on myself: I really do appreciate the downvotes, but could anyone comment why? Because I may be unknowledgable about space flight, but I'm not trying to troll or anything.
And this is why microsats make a ton of sense. Google did the right thing in buying Skybox. Instead of 3-4 beastly (and expensive) sats, send up a dozen much smaller ones and have them use software smarts to talk to eachother. I think that is a much more viable approach longer term for anything such as this in space.
How exactly could you divide a GNSS satellite in that way? Surely you need to transmit the time signal at a particular power level that would required a certain class of antenna and power system. Each of those satellites would need separate control systems so instead of having one fuel tank and thruster you would need several fuel tanks and thrusters.
Frankly the new entrants into the remote sensing market (like Skybox) have yet to make much impact in changing the market. Having a more innovative platform makes little difference to the end user without significant scale (which is currently lacking).
This based on ksp knowledge, so take it with a grain of salt. Typically when you launch a constellation of satellites you want them to all have the same SMA so that they have the same period. Since this one is significantly off it's going to drift relative to the rest of the constellation and isn't likely to provide a useful signal.
The problem is more severe than it may seem. Satellites in the wrong orbit tend to fall to earth sooner (higher partial pressure at lower altitudes). Also, because of the satellites' purpose, they have to reach their design altitude to be of any use at all, for two reasons:
1. Their orbital velocity must agree with the design criteria, so the Special Relativity adjustment in their clock rates will correspond to reality.
2. Their altitude must agree with the General Relativity adjustment made to their clocks, same reason.
If they end up at the wrong altitude, both their velocity and altitude are wrong, and all this deep thinking unravels (and it's not likely that this error can be adjusted for after a launch), as well as the fact that orbital erosion becomes a limiting factor in their lives.
...both satellites are in a safe state, correctly pointing to the sun, properly powered, and fully under control of the ESA-CNES integrated team...ESA teams are investigating the possibilities of exploiting the satellites to maximum advantage, despite their non-nominal injection orbits and within the limited propulsion capabilities. Different scenarios will then be assessed before decisions are taken for a recovery mission
Having been involved in the ground system verification of this system, there are indeed a whole bunch of params that can be tweaked, but these are LARGE anomolies.
This seems like a nearly content free article. Aside from the planned and actual orbits and the dates involved there doesn't seem to be much actual information here.
TL;DR: Something got screwed up during the deployment of the satellites, they're in the wrong orbits but stable, no danger to public, no clue what got screwed up.
While dispelling any possible notion of "blame" or "responsibility". Instead, some out-of-this-world power caused the satellites to "experience" an "orbital injection anomaly".
That's exactly what adults do when they encounter such situation. Talking about blame or looking for someone responsible is not a way to tackle problems of unknown origin that most likely will turn out to be a failure somewhere in the system. Such problems are almost never attributable to a single person.
The Japanese have a saying about this -- "Fix the problem, not the blame."
I can't resist adding that I've always described this quote in just this way (as do others), but it's never far from my mind that it relies on an English idiom, one in which "fix" has two meanings. It's not the same in Japanese.
I think that's the part that annoyed me most about the whole thing. It's pretty obvious someone screwed up somewhere even if we don't know exactly where yet. Whitewashing the whole thing by saying there was an "anomaly" during deployment seems pretty weak. I would rather they be more upfront about it and say there was a failure of unknown origin that they're still investigating. Calling it an "anomaly" strongly implies that there was some sort of unexpected natural phenomena to blame, which although that might be the case is so incredibly unlikely as to not even be worth considering.
Anomaly means an event (failure, in this case) that should be expected only once given a relatively large number of repetitions. To brand it an anomaly does indeed act to dispel notions of poor design because the suggested assumption that goes into it is that if they repeated the launch everything would be hunky dory, which would not be the case if there is a design flaw.
> Whitewashing the whole thing by saying there was an "anomaly" during deployment seems pretty weak. I would rather they be more upfront about it and say there was a failure of unknown origin that they're still investigating.
But ... that's what "anomaly" means -- a failure of unknown origin. It's just a concise way of saying it.
> Calling it an "anomaly" strongly implies that there was some sort of unexpected natural phenomena to blame ...
No, the word "anomaly", at least as used in space science, doesn't suggest that at all. In this context, anomaly means what idiopathic means in medicine -- an outcome of unknown origin.
'Calling it an "anomaly" strongly implies that there was some sort of unexpected natural phenomena to blame [to people who've mostly encountered the term watching too much Star Trek]'
It doesn't have to be natural for it to be an anomaly; but anomaly does indeed specifically means that it's not normal or expected. If there is a failure in the design, then it would be 'normal' (and 'normal' would be wrong) without an adjustment.
Why is the ESA still using Russian rockets? After the recent showing of the Russian Proton-M blowing up all the time (including taking out Europe's AM4R sat) its asinine they keep using Russian designs to do this.
They have alternatives with their own Ariane rocket and US rockets. Maybe its time they started not using the lowest bidder and went for quality instead. How many man hours were lost just now? Just incredible.
Also, I wouldn't put it past the Putin regime to do a black-ops on these Soyuz designs to weaken Galileo to give their GLONASS system a huge competitive advantage.
Proton aside, Soyuz is singly the most reliable launch vehicle on the market, since the retirement of the US Shuttle and ULA Delta II. It has both the longest track record of anything out there, if you look at the entire R7 family, of over 3500 flights. It also has a success rate of over 98% over the past thirty years. The Delta II reached a similar ratio, but over only 140 flights. Also, the Soyuz is one of only three vehicles that Arianspace is able to launch from French Guiana.
Edit: I should probably note, Delta II isn't completely retired yet. So the two are sorta kinda still tied. I've been a Delta II fan for a while, but they're down to selling off stockpiled hardware. Prices kinda went through the roof with the GPS contract going to EELVs. It's a shame, since it's the end of a fairly good track record. But we still have Soyuz.
Oops... Edit 2, since I can't edit this anymore. R7 has not flown over 3500 flights in 60 years, it's flown ~1600 flights. 749 on the model retired in 2011. http://astronautix.com/lvs/soya511u.htm
You're forgetting that it's Russian rockets that constantly refuel and resupply ISS, without any problems. It's just a selection bias.
> Also, I wouldn't put it past the Putin regime to do a black-ops on these Soyuz designs to weaken Galileo to give their GLONASS system a huge competitive advantage.
I wouldn't put it past him anymore that I would put it past Obama. The US would have exactly the same reasons. Believe it or not, Putin is not some sort of evil monster from hell the western propaganda tries to paint him recently, and the US is not some white knight following superior morality. One could actually reasonably argue that the US is more evil than Russia on the international scale. Anyway, the most probable explanation is still "space is hard".
>. Anyway, the most probable explanation is still "space is hard".
I never said it wasn't, I was just exploring the possibility. My point is that a lot of international relations, and this includes spaceflight, works on trust. When one country is habitually lying to the world and receiving sanctions from its partners, that trust is lost. Especially since we know Russian leadership has no problem with politicizing space, namely, its sudden turn-about on RD-180 and early retirement of its part of the ISS. So we know they are willing to be petty in the world of spaceflight for completely unrelated reasons (Ukraine).
Thanks for the downvotes and putting words in my mouth though.
> When one country is habitually lying to the world and receiving sanctions from its partners, that trust is lost.
Well, the magnitude of this is still debatable, once you move outside the america-centric western propaganda bubble. But still, since we're comparing those two nations, I'd like to remind you that United States Government keeps lying to everyone 'both foreign and domestic', so we have exactly equal reasons to trust the US and the Russians.
Fortunately space is usually free of politics, but since you brought that up... did you know that it was NASA who first said (or likely was forced to) to Russians: "hey, we don't like what you're doing with Ukraine, so from now on, we're not going to space together"? The "sudden turn-about on" military engines and ISS prolongation on the part of Russians was merely a reaction to a completely asinine politicization of space by the US Government.
So to fix your sentence, what we know is that "the United States leadership has no problem with politicizing space".
But hell, of course it's the Russia's fault, Holy Freedom Loving America never does anything wrong, or stupid.
Disclaimer: I'm not pro-Russian. I'm anti-stupid-prowestern-propaganda and the usual assuming that America is Good, Russia is Bad. I think we're mature enough to not base our thinking on cold war-era action movies.
You're kidding me, right? Have you ever seen the map of the world?
Geography aside, were Russia really "almost too small to matter", it would have already been bombed by the US over Ukraine for some vague reason like "preventing evil regime from stopping people seeking true democracy".
If you take off the rose-colored, western-biased glasses, you'll see the US as a country that invades and destroys other nations for random made-up reasons like "they have WMDs!!!111oneoneone", that terrorizes innocent citizens of nuclear powers by constantly killing whole families at random by drone strikes, is probably single-handedly responsible for the rise of ISIS and basically looks like its trying to destabilize the whole world to fix its own economy.
So yes, I'll happily listen to USGov saying how Putin is evil, when they stop droning the living shit out of Pakistan.
> were Russia really "almost too small to matter", it would have already been bombed by the US
Russia isn't very important in terms of its economy. Its GDP is ninth in the world[1], just behind Brazil and just ahead of Italy. Most of its GDP is from natural resources. If they didn't have oil and gas nobody would give a fuck about them.
Except for the elephant in the room. NUCLEAR WEAPONS. They have a very formidable arsenal. IMO that's the biggest reason that Ukraine isn't already part of NATO and why the West doesn't already have combat troops in Ukraine. Well, at least if Bush were President. I think Obama's foreign policy is a little bit more nuanced than Bush's was.
Vlad has recently [2] reminded us of his nuclear weapons.
You are right, of course. The big part of why they matter is their nuclear arsenal and fossil fuels (which, what some people in my country happily forget, is what we use to warm ourselves in the winter; but I guess it's excusable, we have summer now after all, and who ever thinks six months ahead...).
I'm not claiming that they're not doing evil things, just that they're not the only ones, and if one starts arguing for possibility of them being so evil as to sabotage a civilian space missions, one would do well to consider other actors to which exactly the same arguments could apply.
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http://en.wikipedia.org/wiki/List_of_smartphones_using_GLONA...
Also, does anyone know how much more accurate the positioning will be with the 3 systems combined? And whether phones will have access to regional systems like for Japan? The Wikipedia pages are enticing on these ideas, but I haven't seen most of it updated in a while.