Domain: rssi.ru
Stories and comments across the archive that link to rssi.ru.
Comments · 28
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Re:Backpeddle?
Actually, they did some research, had a press conference, other researchers pointed out potential problems with the conclusions, and they put some weasel words in the actual published paper. It doesn't matter; the way they went about this, and the weakness of their dust calibration, means that no one will really believe the cosmological interpretation of their results* until more data comes along. That may not take long, according to Nature News
:In addition, presentations given earlier this week at a cosmology conference in Moscow, based on observations from the European Space Agency’s Planck satellite add fresh evidence that what BICEP2 [observed] could be entirely due to a confounding effect of dust.
* That doesn't mean that lots of theorists won't publish papers showing, or purporting to show, or speculating, that this or that implication follows assuming the BICEP2 results are right. That's OK, that's what theorists do. It's mostly harmless, and occasionally leads to something useful even if the original results were wrong.
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ISS deorbiting fear, interesting Russian science
I understand that the Russians are the only ones that can put people in the space station, and that the US serves as the ground control. If Russia refuses to let Americans on to the space station, what are the chances that the US would not coordinate ground control for an exclusively Russian or non-American crew? I've read from a number of sources speculating on this probability. What kind of ground support and communications structure are needed to keep the station operational? With the addition of the alpha magnetic spectrometer, the ISS has become a lot more interesting. : http://ams.nasa.gov/
Perhaps this is one thing that both countries really care about, it's one thing that could serve as leverage between then; a negotiation point.
It's a shame that the cooperation deminishing. The Russians are doing some really fantastic work. They've put a radio telescope in orbit: They launched a radio telescope (Spektr-R) into space. By synchronizing this telescope with earth based telescopes, it can resolve features that are 1250x times smaller than what Hubble can see (40u-arc-seconds vs 0.05 arc-seconds).. Did you know that by pointing all of the radio dishes on one side of the earth, and that knowing the exact time radio waves hit each receiver with atomic clocks, you can out resolve any optical telescope on earth? We can literally see finer details with a radio telescope than we can with our best optical ones (using "VLBI " interferometry). The more separation between radio dishes, the better the angular resolution; and now we have one in orbit that will give us much much better resolving power. We may be able to "see" planets with radio waves. (I'd love to hear from radio astronomers about the practical limitations of this -- real world vs back-of-the envelope)
They only started recently announcing their achievements on their website. Several of my friends joked that the reason we heard nothing for so long was that it was an expensive and embarrassing dud. It works, but they don't market or advertise themselves well. http://www.asc.rssi.ru/radioas...
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Sometimes a neutron is just a neutron.
UD Bartol Neutron Monitor program. http://neutronm.bartol.udel.edu/Welcome.html
Detects high energy neutrons produced by high-speed protons colliding with the Earth's upper atmosphere. TFA is that they have figured out the specific signal for high-energy solar flares.
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Their Website
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Pictures from 200 km
The Soviet Phobos-2 mission returned some cool pictures before its computer failed. I especially like the ones with Mars in the background.
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Re:Let them play WOW
How you can measure your mass in space: link
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Re:Let's not get out of hand about Mars
You're mixing about a zillion different orbits into one recollection.
If you've got enough fuel, just turn and burn man... simple. Of course that takes a heck of a lot of fuel, like your idea of 98% mass fraction of fuel.
A Hohmann TO is the simplest imaginable transfer to design and is pretty quick too. Draw an ellipse that touches both orbits...
http://en.wikipedia.org/wiki/Hohmann_transfer_orbit
A Bi-elliptic is way slow, but if you're making a major/huge change to your orbital parameters it takes less fuel. Enter a giant orbit way the heck out there, then on the return pass enter your new orbit. Handy for inclination changes too.
http://en.wikipedia.org/wiki/Bi-elliptic_transfer
And if you literally have decades of spare time there is the famous "ITN" which takes practically no fuel and takes practically forever, which works by wandering around the various eddies of the Lagrange points or something very vaguely like that.
http://en.wikipedia.org/wiki/Interplanetary_Transport_Network
As for your claim of 98% mass fraction, check out the math on
http://www.iki.rssi.ru/mirrors/stern/stargaze/Smars2.htm
"showing we need add just 2.966 km/s, a shade short of 3 km/s or 10% of the orbital velocity."
and then when you get there you need another 2.5 km/s to match mars orbit, although you can play various gravitational slingshot games to help that out...
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Re:not-so-good?
No such evidence exists for the existence of non-existence of God.
How is that relevant? We're talking about a science class, not theology. God's existence is irrelevant here- the only question is whether or not creationism is science. That's what most creationists don't seem to understand- evolution isn't about atheism. It's about developing and verifying falsifiable models which can be used to make predictions.
Heck, we all learned that pre-Columbus, people thought the Earth was flat.
You were grossly misinformed. Eratosthenes knew the earth was spherical, and calculated its diameter with impressive accuracy hundreds of years before Christ. People opposed Columbus's voyage not because they thought he'd sail off the edge of a flat world, but because they knew how large the earth was and didn't know about the American continent. They (correctly) thought he would starve before reaching India.
Why can't we do that with ID? "This is some people's theory about all of this. This is what most scientists believe about this. Let's move on."
You're abusing the word theory. The appropriate definition in this context is the pedagogical definition provided by the National Academy of Sciences. Creationism doesn't qualify.
And, again, if you did that you'd have to add a caveat to the notion of a rotating earth, and every scientific theory known to humanity.
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Re:"New" rocket.
I'd imagine that the air convections caused by any storm within a 100 miles would easily cause static potentials in the 10-50Kv range on the cable. Also there was an experiment with the space shuttle designed to determine how much electricity would be generated by dragging a tethered satellite which ended when the tether cable burned out. while a space-elevator cable wouldn't be vulnerable to the same currents, all it would take is one good CME and its bye bye cable.
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Re:plasma exit velocity?
Good catch. So 8.5 months for a one-way trip vs. 3 months. I'll take the VASIMR any day of the week.
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Re:Habitable planets must have large moons?
http://www.iki.rssi.ru/mirrors/stern/stargaze/Sprecess.htm Having the moon orbit the earth actually slows the earths gyroscopic precession, which slows the ice ages. Though, I don't think that would be a requirement of a habitable planet. The link explains it well.
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Re:Why no intercontinental cooperation?
Sure, the US could push for a multilateral approach to space exploration. Now, stop and think about the current state of affairs in the 'states and you'll see why this isn't likely to happen.
We do cooperate on some things, like the International Virtual Observatory Alliance.
Which amongst others includes contributions from :
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Re:Proud of the RussiansThe RKA only builds rockets and LEO spaceships, it does not really manufacture or manage satellites and probes. In USA, for example, JPL does most of the satellite work, along with the private sector, so this division of labor is not out of the ordinary.
In Russia, space science is done by the Academy of Sciences, as you can see at the IKI Web Site, for example. Communications satellites are done by other organizations, civilian as well as military.
With regard to your question, the list of current and future projects that are managed by IKI is on that Web page, with English translations in most cases. Here is an example of one of the projects.
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Re:Proud of the RussiansThe RKA only builds rockets and LEO spaceships, it does not really manufacture or manage satellites and probes. In USA, for example, JPL does most of the satellite work, along with the private sector, so this division of labor is not out of the ordinary.
In Russia, space science is done by the Academy of Sciences, as you can see at the IKI Web Site, for example. Communications satellites are done by other organizations, civilian as well as military.
With regard to your question, the list of current and future projects that are managed by IKI is on that Web page, with English translations in most cases. Here is an example of one of the projects.
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Re:Your numbers a little off...That website you linked to is not particularly balanced in its advocacy of nuclear power. There are some serious issues with fast neutron reactors. The first is that the neutron flux has a tendency to damage the reactor materials (look up "neutron embrittlement"), and this problem is worse for fast reactors than for thermal ones. Second, while you do extend the fuel supply, you only do so by a factor of 50 or so (i.e. out to maybe 2000 years). That is not longer than all of human history. Using Thorium might help a bit, but not really all that much.
Third, their sodium reactor design is a safety nightmare - the sodium gets activated, and is of course highly flammable. Every fast-netron sodium reactor design ever built has had some serious accidents related to sodium. That should be telling... The use of lead-bismuth reactors might be an improvement, but those have issues too. Fourth, the plutonium created in an IFR can actually be used to make a bomb, despite what they say. It may, or may not, contain large amounts of Pu-240. In the latter case it will require special care, but you can still make a serviceable bomb (including, but not limited to, so-called dirty bombs). Mind you, any nuclear reactor (this goes for fusion, too) can serve as a source of neutrons to irradiate uranium to make plutonium (the "breeder blanket" approach). Non-proliferation is a pretty serious problem no matter what; I think the solution there has to be some pretty strict international controls.
It's fair to say that the IFR is not a great solution. But a solution is definitely needed.
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Alternative
It is not so well known that the russians have a system similar to GPS. More information at http://www.rssi.ru/SFCSIC/english.html
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Re:This was *exactly* why we here in Europe...
Well, there's always GLONASS.
[sigh] Poor Russian space program.
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A "competing" system already exists!
I'm amazed nobody else has mentioned this yet, but Russia already has an alternative system to GPS. It's called GLONASS (GLObal NAvigation Satelite System.) It's administered by the Russian Federation Ministry of Defense, and it's homepage is http://www.rssi.ru/SFCSIC/english.html
Having had the joy of visiting Russia on a joint military(them) civilian(us) operation, I got to play with one of their receivers. It's pretty cool, very comparable to US military receivers, and I daresay a bit more accurate. Besides which, some of the choices they made in designing their system make sense as opposed to some of the stupid mistakes made with GPS. Check out the website, and then perhaps join me in the desire to have your very own GLONASS receiver and cut yet another string of dependance on the ever-so-bothersome and annoying US government.
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Not necessarily so...Probably the highest stress job there is [aside being an spellchecker at
/.], but the perception is it's ordinary, even mundane.I've only met one astronaut, cosmonaut actually, Gennady Strekalov, several years ago. I'm continually impressed by what these people do, however, they are no longer unique. With the ever expanding circle of those who have been above the atmosphere they become less distinct in the crowd.
I'd still dream of being an astronaut, but not at the expense of getting in the way as a bloody tourist, whom then comes back and poo-poos the whole shebang. It was quite an accomplishment for Sir Edmund Hillary to conquer Everest, particularly with what technology and the environment offered him in the way of equipment and protection from the elements, yet many standing upon his shoulders, with all today's advancements still fail and risk life the same as those aboard the Challenger did.
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All your .sig are belong to us! -
My school's sattelite project
My school (Knox Grammar in Sydney, Australia) has a joint satellite project with another school in Sydney, Ravenswood and a school in Russia.
The satellite is named "Kolibri" and each school has equipment for communicating and recieving data from the satellite.
The students are performing actual research regarding "the structure and intensity of low-frequency electromagmetic fields around the Earth".
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If it were only so easy.Alas, Uncle Sam sez no go.
See, the majority of GPS chipsets and firmware (and off the shelf units) don't work so hot above certain altitudes and speeds. (as I recall anyway) Reason: Uncle Sam doesn't like people using GPS for ICBM guidance.
Now the RUSSIAN system (called GLONASS) would be a better bet. Only catch is that it isn't quite as accurate as GPS.
However if you are just trying to hit a county it would probably do just fine...
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The most useful low-bandwidth servicesGPS uses 50bps half-duplex broadcast transmission to achieve quite amazing results. GLONASS uses similarly low bit-rate with essentially the same results. WAAS uses 250bps.
What interesting things, besides positioning, can be done with low bit-rate channels?
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Re:Space anyone?
I, for one, am eagerly awaiting 10^9 meter baseline radio interferometers. Also, if you build an optical interferometer of that kind of scale, you can pick out the canals on Mars from Alpha Centauri. Or vice-versa.
Well, there's always the Japanese HALCA satellite, part of the VSOP project. This was the first working satellite for a Space VLBI mission, and it had the expected problems with dealing with interferometry between quickly moving objects. True, it's apogee is only at 21 400 km, so it's not quite at the 10^9m level, but it's close.
While HALCA itself is nearing the end of its useful operating lifespan (There were some problems with the satellite losing its targetting that resulted in using up the maneuvering fuel faster than planned), the success of the mission has helped get the Russian Radioastron project back on its feet, and pave the way for other Space VLBI projects.
The main problems in space interferometry have already been tested and dealt with, and there's been some work in the radio astronomy community for dual-satellite interferometry, once some of the second-genaration systems like VSOP-2 and ARISE are in space in a few years. With two satellites each with a 50 000km apogee, we can actually hit the 10^9 meter baseline level.
(Yes, I know a moderate amount about this from my work with the S2 data recording system which is used at a number of radio observatories around the world for VLBI.)
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Re:Russians have no clue?
Please remind me again what your claim to being an expert was?
I didn't claim that I'm an expert (my field is optics / astronomy) - if you'd read what i wrote you might have seen that the information i was passing on was from one of the original engineers on the project. His name is Yuri Samarkin. He used to work for this guy. He's not there now. I think he rattled too many cages.
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Re:Age of transparency and misc gps comments
The real big issue is to get GPS useable for the FAA's WAAS system. Right now other countries are not taking it serious because of Selective unAvailability (S/A or SA).
The other issue is the Europeans keep trying to get into the GPS frequency range. As long as its military system there isn't much opposition. If its a fully civil system used for aviation then its much more likely that GPS will maintain its exclusive use of the frequency.
Basics of how GPS works:
Sats send out the time from their atomic clocks.
The receiver figures out what time it is and difference between its time and the received time.
It calculates its position based on the time difference between the sats and their position.
It gets a better idea of the real time and keeps updating its time/position. The internal oscolators can be within 10 ns of "real time" even on the cheap GPS receivers.
To keep the bad guys from using GPS against the US, the sats will delay their time transmissions by some pseudo random time.
The device to do this has never worked on the older sats and is broken on others (I think prn #1, #20, #6)
As far as if the US military receivers are any better than the cheap handhelds, I'm not sure they are better. Trimble has had the best receivers in the world for some time and their best are not the military systems (but use the encrypted signal to help do some phase calculations). There have been reports that the better marine units were giving better position reports than the military units the last time S/A was turned off.
Also the Russian system GLONASS has a number of problems and may never get any more sats launched. They currently have 10 listed as working and another 9 listed as unusable and there should be 28 sats total. There had been rumors that Sweeden was going to by it.
You can do DGPS over the internet too. -
USSR Equivilant = GLONASS
The former USSR already has an equivilant to American GPS. The GLONASS constellation has been operational since about 1986.
The GIS company I work for has receivers that use both GPS and GLONASS for most of our survey work. When used in differential mode, these things are capable of sub-meter accuracy. (usually less than 0.5 meters error)
Still, turning off SA is great news..
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Re:Spam, the ultimate coders itch.
OK then...the headers say it came from ras5.icp.rssi.ru. According to www.rssi.ru, that is the remote access service of the Institute of Chemistry and Physics in Moscow. RSSI is the Russian Space Science Internet, an non-profit ISP for the scientific community in Russia.
I looked for an account administrator to send this to, and I found marina@rssi.edu.
Please do not slam this woman's mailbox. Send a well-constructed, concerned letter. The spam is not her fault, but it may be her responsibility to deal with it.
Mike
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Re:Spam, the ultimate coders itch.
OK then...the headers say it came from ras5.icp.rssi.ru. According to www.rssi.ru, that is the remote access service of the Institute of Chemistry and Physics in Moscow. RSSI is the Russian Space Science Internet, an non-profit ISP for the scientific community in Russia.
I looked for an account administrator to send this to, and I found marina@rssi.edu.
Please do not slam this woman's mailbox. Send a well-constructed, concerned letter. The spam is not her fault, but it may be her responsibility to deal with it.
Mike
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