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    Russian Space Program: News & Discussion

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    Vladimir79

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    Russian Space Program: News & Discussion

    Post  Vladimir79 on Tue Aug 18, 2009 6:46 pm

    Russia will launch 5 new satellites
    18.08.2009

    Enterprise Satellite Communications, a public satellite telecommunications operator in Russia, intends in the coming years to upgrade its orbital grouping of five heavy satellites.

    "The implementation is the" 4 +1 "means the creation of five spacecraft heavy class." Express-AM4 "is in production, signed a contract for the establishment of two spacecraft Express-AM5, and AM6-Express", has plans to aids Express-AM7 and AM8 Express "- informed the Acting Director General, Russian Satellite Communications Company Yuri Prokhorov.

    According to Interfax, the satellite "Express-AM8" will go into orbit, along with the Office Express-MD2. Same way in February 2009 launched the Express-AM44 and Express-MD1.

    "At the Express-AM8" prepared all technical documentation, determined face, understand the problem of its use. The satellite will meet the challenges in the area of Africa, the Atlantic and South America, "- said Prokhorov.

    Head of Satellite Communications Company also reported that sources of funding the creation of Express-MD2 "are under negotiation. "Financial support for the construction of this unit we will find. State enterprise" Space Communication ", and enlisted the financial resources will enable bank to implement this program," - said Prokhorov.

    After the restoration of the orbital grouping Satellite Communications Company intends to implement the new program development. "We must determine, based on world market trends in communications and broadcasting, where and how to develop our group after the completion phase of renewal," - concluded the head of the company.

    The concept of development of space communications specialists of Russia is developing a co-NII radio.

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    Vladimir79

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    Testing Russia's advanced space transportation system

    Post  Vladimir79 on Wed Sep 02, 2009 6:35 am

    Testing Russia's advanced space transportation system in an unmanned version would begin in 2015, manned - in 2018
    01/09/2009

    MOSCOW, August 31. (ITAR-TASS). Testing Russia's advanced space transportation system (PKTS) in an unmanned version would begin in 2015, manned - in 2018. Starting PKTS ships will be scheduled from Baikonur in eastern Amur region. Told in an article published in the weekly "Industry", Deputy General Designer of RSC Energia, the chief designer of manned systems Nikolai Bryukhanov.

    "Tests of the spacecraft in an unmanned version is scheduled to begin in 2015, and in manned - in 2018 - said the chief designer. - At this point the ship should be a key element of Russia's manned space flight."

    According Bryukhanova, "the system will consist of a base manned spacecraft and a few modifications, built on its basis." Basic version - manned transport craft a new generation, - explained the representative of RCM. - It is designed to service the orbiting station - they deliver crew and cargo and then return to Earth, as well as for use as a crew return vehicle.

    In RCM expects that the modifications of the ship will solve specialized tasks, such as flights to the Moon, maintenance and repair of satellites in low earth orbits, long-term - up to a month - autonomous flights to various studies and experiments, as well as delivery and return of the increased quantity of goods in unmanned gruzovozvraschaemom version.

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    Vladimir79

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    Russian Earth Observation, Weather satellites:

    Post  Vladimir79 on Sat Nov 20, 2010 10:01 am

    Broke down Russian satellite


    Russia's only high-resolution satellite Resurs-DK1 "out of order. As reported by Interfax, the unit stopped working a few systems and it can no longer be used for other purposes. "As far as I know, official documents have not yet been." Resurs-DK1 "no longer works" - said the deputy director of RDC, which provides services to satellite imagery of the Earth, Olga Gershenson.

    A source in the space industry said that experts now TsSKB Progress "are trying to fix the unit. Resurs-DK1 "launched into space June 15, 2006 from the Baikonur Cosmodrome for remote sensing in the visible spectrum. Transmitted to the device information is used for mapping natural resources, environmental monitoring, tracking, emergency and some research. Expected lifetime of the satellite is three years.
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    Ogannisyan8887

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    Russia plans 50 space launches, 10 ICBM launches in 2011

    Post  Ogannisyan8887 on Sat Jan 08, 2011 7:00 am

    Russia plans 50 space launches, 10 ICBM launches in 2011


    2011-01-03



    Rocket launch at Plesetsk (mil.ru)


    Russia plans to conduct about 50 space launches from three launching pads and 10 combat training and test launches of intercontinental ballistic missiles in 2011, Voice of Russia reports.

    The International Space Station program provides for ten launches, including four manned missions and six flights cargo ships from Baikonur, Voice of Russia reports. In addition, Russia plans launches of Glonass-M satellites, a telecommunication satellite and a number of military satellites.

    As BarentsObserver reported, Russia planned to launch a Glonass-K satellite from the Plesetsk Space Center in Arkhangelsk Oblast on December 28, but the launch was postponed until 2011 because the ground complex was not fully prepared to navigate the spacecraft, RIA Novosti reports.

    Thirty one space launches were carried out in 2010.

    Russia’s Strategic Rocket Forces plan to carry out ten intercontinental ballistic missiles (ICBM) combat training and test launches in 2011, Voice of Russia reports, citing the Ministry of Defense.

    In 2010, Russian rocket forces had a total of five ICBM launches, including two successful tests of RS-12M Topol missiles.
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    GarryB

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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Sat Jan 08, 2011 7:39 am

    I have read that when they launch satellites into geostationary orbits from the Plesetsk cosmodrome they have to slingshot the satellite around the moon to get it into the right orbit because of the northerly position of the launch site.

    Increases in launches will be good.
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    nightcrawler

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    COSMOS Question Thread

    Post  nightcrawler on Sat Jan 15, 2011 5:58 pm

    Here is my first entry


    I need some clarification regarding the following sentence
    This shows the evolution of the UR-500 space launch vehicle. For many years, Westerners believed that the clustered modules of the first stage were strap-on boosters. These were in fact only propellant tanks and not self-contained stages
    Ambiguity of this sentence is the word self-contained stages; isn't this very word also mean strap-on boosters ??
    Also by saying only tanks does that mean that the main engine was inside missile body & then surely the rear end of these tanks wouldn't have any nozzles protruding out; though I don't have any clear image about it
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    GarryB

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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Sun Jan 16, 2011 5:12 am

    These external tanks are like the large centre tank on the Space Shuttle... they carry fuel but have no engine at their base... the fuel is fed into the central rocket vehicle and it burns the fuel... just like drop tanks on a conventional aircraft.

    It is just a clever way of carrying extra fuel without adding length... when the tanks are empty explosive bolts will likely fire at the top end of them and then the bottom to release them from the rocket and they will fall back and burn up as they reenter the atmosphere.

    The sentence is not ambiguous, just poorly constructed.

    For many years, Westerners believed that the clustered modules of the first stage were strap-on boosters. These were in fact only propellant tanks and not self-contained stages

    In other words because they didn't know any better they assumed the tanks were strap on boosters.
    They now know that they are just propellent tanks... if they were booster rockets they would be self contained stages of the rocket... ie the booster stage that would burn on lift off with the first stage main engines.
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    GarryB

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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Sun Jan 16, 2011 7:10 am

    Nice.

    Together with the nuclear engined Space Tug they are developing this could be a very interesting combination.

    One of the uses of the nuclear engined space tug was to clean up some of the space junk in orbit, but towing a spaceship to the Moon or even Mars could be other jobs assigned to it.
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    Andy_Wiz

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    Re: Russian Space Program: News & Discussion

    Post  Andy_Wiz on Mon Jan 17, 2011 10:49 pm

    BULL**** russia In Soviet Russia satellites put itselves out of the orbit...(Some jewish woman said that)

    The sattelite seems to be OK, there was a scare as it was sinking down itno lower LEO so they had to FLY it up a bit(and shook up that heap of junk a bit:lol: ) It is explained on novosti-kosmonavtiki forum...
    Manufacturers press release - Samspace

    If it brooke down on 11.19 how it could have been making photos of Chinese shipyards etc. up till 3.12

    lol!

    Here you go - http://www.ntsomz.ru/news/news_center/rdk21112010

    Anyway no official confirmation yet... VPK.NAMe is trashy source TBH/ dunno



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    Re: Russian Space Program: News & Discussion

    Post  Andy_Wiz on Mon Jan 17, 2011 11:16 pm

    OOps people on spacenews forum say that it seems because it went so high up its resolution got f***ed up... I can't say if its true you may compare the photos in previous post link to this one -



    (It is a Sayano-Shushenskaya Dam that had a disaster in 2009)

    However I suspect that better resolution photographs are classified..
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    GarryB

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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Tue Jan 18, 2011 12:34 am

    That is good news Andy.

    By the way... clarification of adjusting orbits... the orbit height of an object in earth orbit is determined by its speed. The faster it goes the higher its orbit till eventually it stops falling back into orbit and leaves earth completely.

    If the orbit was too low and they fired rocket thrusters to climb the satellite would indeed go up... but then it would fall back down because it doesn't have the speed to maintain the higher orbital path.

    If a satellite gets too low and starts to scuff the atmosphere the extra drag slows it down even faster and it will reenter the earths atmosphere.

    Thanks for the positive news.

    Hoof: regarding the space tug 99% of the tug that needs development is the nuclear propulsion which the Russian government said it was spending some time ago. Once developed the new engines will operate for months, so while they are not as powerful as chemical rockets they will burn continuously for most of the trip.

    For orbital tug it will likely approach targets from behind to catch up with them gradually so it can grab the failed satellite and take it to the ISS for repair or inspection, or for older satellites it could throw them directly at earth where they will hit the atmosphere at a steep angle at very high speed and burn up in the atmosphere, or if it is too heavy it could break bits off and fire them straight down for burn up.
    Just speeding up and slowing down to change height and manoeuvring left or right to get things on different orbits it could operate for decades on nuclear propulsion.

    For a trip to the moon or mars however is where they will shine... a conventional 3 stage rocket will burn for a total of less than 20-30 minutes and once you reach your top speed that is the speed that you will keep travelling at in zero gs all the way to where you are going. When you get near your destination you need to use more rocket power to slow down and enter orbit of the destination, but after burning off all that fuel to leave earths orbit the craft will be much lighter so less fuel will be needed.
    With a nuclear rocket after 30 minutes after launch you will be travelling at a mere fraction of the speed of a chemical rocket... but by the end of the week you will likely be travelling faster and the next week much faster still. Because it is not as powerful you will also need to slow down earlier so the nuclear rocket will be operating all the way to the destination... which means the craft wont be operating at zero g, though 1g acceleration would be very unlikely... it might be 0.1g which at least makes things easier.
    With zero g you need fans going all the time otherwise the air would not circulate and you could suffocate if you stayed in one place too long is just one example of the problems of zero g.

    Ohh... that will would be great for snatching few of those US military satellites...

    You are getting more American all the time... only an American would think of doing that. I guess that is what keeps them where they are.
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    Re: Russian Space Program: News & Discussion

    Post  Hoof on Tue Jan 18, 2011 5:46 am

    GarryB wrote:
    Ohh... that will would be great for snatching few of those US military satellites...

    You are getting more American all the time... only an American would think of doing that. I guess that is what keeps them where they are.

    Haha... how can i get more American ? its snatching American satellites i'm talking about XD I'm Russian-American BTW lol

    There isnt anything wrong with stealing other country's technologies... how you think soviets got their first intercontinental bomber and plans for first nuclear bomb ? =)
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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Tue Jan 18, 2011 6:16 am

    Actually if it wasn't for the ANT-25 flying 9,000km non stop from Russia to the US there wouldn't have been a B-29.

    When the ANT-25 landed the US congress were just about to cancel the B-17 because it wasn't deemed necessary.

    And the first nuclear bomb was created on US territory, but was the product of the best minds of the time from dozens of countries around the world.

    its snatching American satellites i'm talking about XD I'm Russian-American BTW lol

    I know... what I meant was that Russia would have done rather better if she was a bit more ruthless and underhanded like the US is.

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    Re: Russian Space Program: News & Discussion

    Post  Pervius on Tue Mar 08, 2011 10:18 am

    Did Russia ever match US PRoject Rover for space tugs to move satellites around?

    Somebody built crazy space tug able to do 90* directional changes at high speed. I've seen them watching the stars at night. Likely using explosions to alter direction. No oxygen in space for explosions to be seen.

    Russia needs to do something about lack of Space awareness/capability. Chinese launched entire GPS Constellation around Earth in 12 months.

    Battle now looks like US-China for Space Control with Russia still looking at 2 dimensional plots on computer screens, no 3 dimensional situational awareness.
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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Wed Mar 09, 2011 2:37 am

    Did Russia ever match US PRoject Rover for space tugs to move satellites around?

    The Russians are working on a nuclear engine for operating in space, though it does not use nuclear explosions for propulsion... more likely it uses a nuclear reactor to generate lots of heat and electricity and use that to accelerate small particles like an ion engine of very long operational duration.
    One proposed use is to clear debris in orbit, and the main use of as a tug to take spacecraft on long journeys like to the moon or mars or further.

    Somebody built crazy space tug able to do 90* directional changes at
    high speed. I've seen them watching the stars at night. Likely using
    explosions to alter direction. No oxygen in space for explosions to be
    seen.

    90 degree changes would be near impossible... the g forces alone would tear the craft apart... orbital speed is above 7km/s... to stop travelling forward at 7km/s and then accelerate in a tangent 90 degrees to 7km/s would require two enormous forces... there is no air to push against so wings or control surfaces wouldn't cut it... it would have to be rockets and there aren't any with that sort of performance.
    An explosion is perfectly feasible in space... an explosion requires oxygen to combust a fuel... plastic explosive contains its own oxygen supply and therefore works where there is no oxygen like underwater and in space... and you would certainly see the flash. The explosion needed to stop an object in orbit and redirect its flight path 90 degrees would need to be nuclear and would destroy the thing it is redirecting.

    The shoemaker levy comet that hit Jupiter a few years back created a series of huge flashes... no oxygen there, but when material is heated to tens of thousands of degrees it gives off its own light. Earths main source of light... the sun does not burn with oxygen either and it is clearly in space.

    Russia needs to do something about lack of Space awareness/capability.
    Chinese launched entire GPS Constellation around Earth in 12 months.

    Russian space tracking radars are the best available anywhere. The US compared and were found to be less capable. A GPS constellation is for navigation and offers no space awareness at all.

    Battle now looks like US-China for Space Control with Russia still
    looking at 2 dimensional plots on computer screens, no 3 dimensional
    situational awareness.

    I rather think you are overestimating China and significantly underestimating Russia here.

    When the next two US shuttles make their flights the ISS will be totally reliant on the Russians for support and transport.

    Last year despite the failures the Russians still had twice as many launches as the US.

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    Re: Russian Space Program: News & Discussion

    Post  Pervius on Thu Mar 17, 2011 2:55 pm

    ""90 degree changes would be near impossible... the g forces alone would tear the craft apart...""

    They thought the G-forces from this propulsion method would be too much for anything to survive:

    www.youtube.com/watch?v=uQCrPNEsQaY

    In the 1950's it was proven to be wrong, things can survive using explosives as propulsion. Unmanned objects in space could have course altered using explosives. If it did a maneuver turning the blast plate behind where it wanted to go, shoot out explosives with a timed fuse....boom! Explosion sends object in a new direction if that charge was sufficient. That's using 1950's technology proven to work here on Earth with our strong gravity down here. Gravity in space is a bit weaker.

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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Fri Mar 18, 2011 12:53 am

    That's using 1950's technology proven to work here on Earth with our strong gravity down here. Gravity in space is a bit weaker.

    In the vacuum of space the effect of a blast is almost non-existent.
    In the earths atmosphere an explosion is basically the sudden release or creation of a large volume of gas rapidly in a confined space.
    Inside the shell case of a rifle bullet there is a small amount of powder propellent that is sensitive to heat. Pulling the trigger to release the hammer to hit the firing pin crushes a small amount of very sensitive material... either lead fulminate or mercury fulminate inside the primer. When crushed it converts a solid material directly into a gas generating heat and light in the process. This shower of hot sparks enters the cartridge case and ignites the propellent which then burns. It contains all the three requirements for fire... fuel, oxygen, and heat. The propellent contains stored oxygen and fuel and the primer being hit provides the initial heat to get the reaction going.
    In the confines of the cartridge case the conversion from solid to gas generates a lot of heat and light and a huge increase in pressure. In such cases the forces will take the line of least resistance... so the walls of the chamber are too strong and the bolt blocks rearward movement so the point of failure will be for the gas to push the bullet down the barrel for the pressure to release and escape and normalise with the outside pressure.
    If the barrel was wielded shut the next point of weakness would likely be for the bolt to blow open... if it was completely sealed then as long as the whole structure was strong enough it would simply contain the pressure.

    The point is that the volume of gas created is limited by the size of the powder charge. If you were to launch that small propellent charge out of a space ship and detonate it (it contains chemicals that release oxygen during the burning process so it works in the vacuum of space) there would be no pressure build up as it is not contained. Any fast moving gases would have little effect as they spread in a sphere so their expansion force would rapidly diminish with distance.

    What I am trying to say is that the act of firing the propellent charge out of the spaceship probably had more effect on the spaceship than the explosion would.

    You need to look at nuclear explosions in space to get impulses on the craft that would be meaningful... and how could you do that with no one on Earth noticing all the extra suns in the sky?

    The weight of shielding of a nuclear blast would make the spaceship dreadfully inefficient... just as nuclear propelled bombers were tried in the 50s and 60s and it was found that with the weight of shielding the payload was pathetic and not worth the effort.

    They thought the G-forces from this propulsion method would be too much for anything to survive:

    And before the invention of the internal combustion engine it was thought that no one could survive driving a steam powered car at more than 50km/h because the air would go past so fast you wouldn't be able to breathe.

    The invention of a death ray as a weapon was also considered impossible because anything powerful enough to kill an enemy would kill the user first because they are closer to the death ray.

    Then America goes and launches the X-37b. Looks like Russia should have
    fixed Polyus's guidance software and put in space long ago eh?

    The militarization of space has begun.

    In their rush to dominate space, they forget how much they rely on space based assets and how vulnerable they will be when their rivals develop weapons similar to those they are developing themselves.... talk about Pandoras box.
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    Re: Russian Space Program: News & Discussion

    Post  nightcrawler on Fri Mar 18, 2011 11:40 am

    @Garry; Pervius
    What I am trying to say is that the act of firing the propellent charge out of the spaceship probably had more effect on the spaceship than the explosion would.
    I think Pervius is only talking about course change using explosions albeit small one & not the actual acceleration of the space body...
    For the acceleration purposes propellent charge out of the spaceship is effective however for the latter small explosions can be effective provided for every manoeuvre you aren't starting/shutting engines burning & rather wasting fuel.
    If you see the video small balls are ejected from the vehicle & at very close proximity the explosion occurs completely outside the framework of the space vehicle [this can be ineffective as reasoned by Garry]. Explosions however must be channelled to a duct where there shockwave can be effective a lot more to spacecraft..

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    Re: Russian Space Program: News & Discussion

    Post  Pervius on Fri Mar 18, 2011 4:54 pm

    ""In the vacuum of space the effect of a blast is almost non-existent.""

    In 2007 Comet Holmes blew up in the asteroid belt. In the vacuum of space that explosion disturbed the asteroid belt....notice all the asteroids flying around now in the solar system hitting the sun? Explosions in space can give objects motion. Pray we survive the asteroid belt being disturbed.
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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Sat Mar 19, 2011 8:05 am

    In 2007 Comet Holmes blew up in the asteroid belt. In the vacuum of
    space that explosion disturbed the asteroid belt....notice all the
    asteroids flying around now in the solar system hitting the sun?

    Was it the blast from the impact, or the physical kinetic energy of a large body hitting another and effecting both their courses.

    Also don't believe what you see on star wars or even science based documentaries that always depict the asteroid belt as densely packed with rocks slamming into each other and moving all over the place.

    If the real asteroid belt looked like that it would have an enormous amount of matter and would have formed into an enormous solid planet by now.

    The reality is that all the material in the entire asteroid belt would make up our moon and if you broke our moon into lots of different sized chunks and took them out to an orbit between Earth and Mars the ring is enormous and the bits and pieces that make up the asteroid belt are so far apart if you were standing on a significant piece the nearest other piece would be millions of miles away and not visible to you.

    Asteroids hitting asteroids do happen and when they do the kinetic force is enormous because of the weights and speeds involved. Two very large objects passing very closely by but not actually touching each other will effect each other by each objects gravity field but if they impact each other there is very little effect from the "blast".

    In fact during tests with very high velocity guns firing into targets for research into asteroids found that if the target is a rubble pile... basically a collection of gravel and larger rocks held together by gravity rather than being a single rock that firing a high velocity projectile into it will temporarily disperse some of the material but the majority of the material will fall back under gravity and the rubble pile will continue largely the way it was before. Normally colliding two objects will result in new trajectories for both objects, but in this case the impact is absorbed by internal changes in the rubble pile.

    Only a small amount of material will be vapourised and released as a kind of gas and this gas would disperse and not blow nearby objects off course.
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    Re: Russian Space Program: News & Discussion

    Post  nightcrawler on Sat Mar 19, 2011 2:51 pm

    @Pervius
    ""In the vacuum of space the effect of a blast is almost non-existent.""

    What about CONTAINED explosions, within special various ducts protruding out of framework.
    Each explosion in each particular duct can really economical in coarse changing..
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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Sun Mar 20, 2011 12:33 am

    Each explosion in each particular duct can really economical in coarse changing..

    You are talking about a rocket thruster... the problem is velocity.

    To be able to use the rocket thruster a lot it is very important that the material ejected is very light so you can carry lots of it. Because you want it to be light for it to be effective you need to eject it very fast.

    Think of it in terms of a bullet from a gun.

    Using a simple bolt action rifle with no muzzle brake to deflect the gas to reduce recoil and no reloading mechanism to soften the recoil when you fire a gun you are accelerating a small metal weight (the projectile) with a large volume of gas (which is the burnt propellent) and you are also accelerating that gas as well.

    The energy calculation on the ground is effected by the atmosphere and gravity but in orbit those effects are eliminated. There is gravity in orbit of course but because everything in orbit is "falling" at the same rate is can be ignored.

    The energy calculation in orbit... say during an EVA, is the mass and velocity of the bullet plus the mass and velocity of the gas is generating energy in one direction. As it is a balanced system... for every action there is a reaction, using the mass of the rifle you can determine how fast in the opposite direction to the bullet and the gas that the gun will travel under recoil.

    Lets say you throw the gun muzzle forward perfectly so that it doesn't spin in any direction and you have fitted the trigger with a small mechanism that after a period of time will pull the trigger and fire the round in the chamber. So you throw the rifle at... say 10m/s... when the rifle fires the equation starts as the weight of rifle times its speed is its forward momentum, but the new force of the bullet and gas mass plus velocity combined which also has a momentum which opposes the momentum of the rifle when it fired. These forces are directed in exactly opposite directions and so counter each other.

    What I am trying to say is that the momentum of the bullet and gas is high because its velocity is much higher than the momentum of the rifle even though the rifle is much heavier.

    Rockets use separate stages to minimise weight because when you are accelerating an object weight is the enemy to a limit. On earth you can throw a cricket ball further than you can throw a helium filled ballon because a large very light object doesn't push its way through the air very efficiently. You can however throw a cricket ball further than a shot put because the cricket ball has the balance of being heavy enough to move through the air efficiently but not being so heavy it is hard for you to accelerate it to high enough speed to go somewhere.
    With more power the result changes... instead of your arm accelerating the object if you use powder propellent like in a cannon that heavy shot put will be better than a cricket ball because the cannon will be able to accelerate the shot put without destroying it and with the high speed the heavy shot put will be much less effected than the cricket ball and so will retain its speed better and travel further.
    Reshaping the shot put into a bullet shape and spinning it will further increase its range.

    Based on all of this what I am saying is that to stop an object in orbit and make it turn 90 degrees is impossible.
    In orbit there is no air to push against so wings or control surfaces don't work... the only way to slow down is to point a rocket engine or gas engine in the direction you are travelling and fire material forward so that the equal and opposite reaction is to slow you down.
    Travelling at 7km/s in orbit will take a lot of very high speed material to slow you down.
    Remember it took a three stage rocket with up to 60 tons of fuel or more to get 2-5 tons up to orbital speed.
    Obviously once in orbit it is easier to slow down but this normally involves slowing down enough to re enter the earths atmosphere which does the rest. A 5 ton object might need 60 tons of fuel to get into space and up to orbital speed, but when it is launched it weighs 60-70 tons so it needs powerful rockets and lots of fuel to get this airborne and moving. Once it is moving as it drops stages it needs less power and less fuel to keep on accelerating. Once it is in orbit it doesn't need a huge powerful engine to slow down or speed up because it is much lighter... however because it is much lighter there is less energy available to speed up or slow down too.

    To manouver in space while in orbit you can turn a rocket motor sideways to change your orbital path, but to gain height you need to go faster and to descend you need to go slower.
    If you were in a stable orbit and you wanted to climb if you directed your rocket engines downwards and fired them for 10 seconds you would go up... till you ran out of momentum and then you would fall back down and eventually you would end up at the same height you were before you fired your engines.
    To climb to a higher orbit and stay there you need to be going faster so to climb you turn your rocket engines backwards and fire them for 10 seconds to accelerate and that will make you climb to a higher orbit.

    To turn 90 degrees... well the thing about acceleration force is that it is just like gravity... it is actually measured in units of gravity, so a high speed turn might be 6gs or 9gs.
    The g of a turn is determined by its angle and the speed you are travelling at.
    Try it with your car... somewhere safe.
    Drive at 10km/h and turn rapidly 20 degrees and then straighten up. No big deal really at such a low speed.
    Accelerate to 50km/h and turn rapidly 20 degrees and then straighten up... you felt the difference?
    The faster you are travelling the more you want to keep going in the same direction.
    In the first test you probably felt nothing but at 50km/h you will have felt your body wanting to continue straight with the car seat and steering wheel pulling you 20 degrees off course.
    Modern fighter jets can turn at about 16 degrees per second at high subsonic speed which probably equates to about 9 g.
    The effect of gs is proportional so doubling the speed more than doubles the g force.
    At 7km/s the g forces would rip anything man made to pieces in a 90 degree turn.
    To do it with a rocket you pretty much have to swap the gun for the ammo... in other words the bullet and gas is the satellite and the gun is the rocket used to stop the projectile... the problem is that there is not enough matter left to then accelerate what is left to orbital speed.

    To turn 90 degrees in orbit would take hours at least and would burn an enormous amount of fuel with a side thruster burning for a very long time... in the 3-5 minutes it is visible overhead the turn would be very difficult to see as the rotation of the earth makes the flight path appear curved anyway.

    Pervius

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    Re: Russian Space Program: News & Discussion

    Post  Pervius on Mon Mar 21, 2011 7:50 am

    """Based on all of this what I am saying is that to stop an object in orbit and make it turn 90 degrees is impossible."""

    Not for the last 50 years.

    Mass of object (A) X's speed energy (B) = needed force to stop object (C).

    C times Mass of Object plus intended speed energy in intended direction for course correction (D).


    If you can release sufficient energy course correction can be attained. Of course true calculation is a little more complex needing microgravity factored in with a few other variables to fire at precise time to maintain orbit in intended distance from planet. It's not rocket science, it's explosive propulsion.

    You could do the experiment by putting a tennis ball on a string and spin it around you with your arm. Have a timed small explosive charge on the bottom of the tennis ball so as you spin it around you...tiny explosive charge drops below tennis ball as it's flung away by a spring and explodes 7 inches below ball...tennis ball makes course correction and goes over your head. If you built simple experiment correctly, even course correction on Earth can be done with explosive.

    Very simple experiment. Tennis ball always survives course correction. Miniscule explosive needed for course correction.



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    GarryB

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    Re: Russian Space Program: News & Discussion

    Post  GarryB on Mon Mar 21, 2011 8:32 am

    If you can release sufficient energy course correction can be attained.

    The energy required to redirect even a small satellite 90 degrees while travelling 7km/s would be enormous and destroy the satellite in the process.

    Lets assume it is a 10kg satellite... what 10 kg rocket exists on the earth that can accelerate itself to 7km/s even with no payload even if all 10kgs was fuel and the rocket components took up no mass.

    That is not fair you say... who would use such a light satellite... actually I am not being fair in your favour because the heavier you make the satellite the more momentum it has and the more energy exponentially it will need to both stop and change direction.

    The g forces involved in turning 90 degrees at 7km/s would kill most life forms and destroy most man made structures.

    BTW tennis balls and explosives is not a good mixture....

    Pervius

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    Re: Russian Space Program: News & Discussion

    Post  Pervius on Tue Apr 05, 2011 6:20 pm


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