Niska Orbita

[bigvlada]

Pošto se onaj jedan topic rasplinuo na sve strane, splitovao sam ga na više manjih, radi preglednosti. Dekssu ću odgovoriti tamo na zadnja dva posta kako bi se održao tok diskusije a sve naredne neka idu u odgovarajuće teme. Ovde možemo da raspravljamo o svim aktivnostima koje se tiču aktivnosti u niskoj orbiti. Tu spada sve vezano za orbitalne stanice, teretne i brodove sa ljudskom posadom kao i satelite.ESA lifting body entry vehicle on the cusp of final approvalBY STEPHEN CLARKSPACEFLIGHT NOWPosted: June 10, 2011 PARIS -- The European Space Agency should formally approve this summer the construction of an Italian-led demonstrator that will launch into space on a rocket, fly back to Earth like an airplane and parachute into the Pacific Ocean, according to the mission's project manager. Artist's concept of the Intermediate Experimental Vehicle plunging back to Earth throught the atmosphere. Credit: ESA The Intermediate Experimental Vehicle is on track to blast off on a Vega rocket in late 2013, speed around the Earth at a peak altitude of nearly 300 miles, then drop from space and fly back to Earth with the help of aerodynamic flaps and a parachute. Giorgio Tumino, the IXV project manager at ESA, said the craft passed its final critical design review in May. Senior ESA officials are now firming up the spacecraft's cost before signing a contract with Thales Alenia Space of Italy to build the vehicle. Formal approval for the contract signature should come from an industry planning committee meeting at the end of June, Tumino said in an interview. "We are in quite an advanced stage of the program," Tumino said. "It's not paper, but it's reality. There is an internal European process for the approval of all the activities. We should be able to sign the actual contract by the end of this month." Sandrine Bielecki, a Thales spokesperson, said the company signed an agreement to be the IXV's prime contractor in 2009. Individual contracts for design work and hardware production are handled separately. After ESA and Thales sign a final production contract, there is a 27-month schedule planned to manufacture parts, build the spacecraft and test it before shipping the vehicle to the launch site in Kourou French Guiana. The total cost of the mission is about 100 million euros, or about $143 million. ESA has the money to build the spacecraft, but funding for Vega launcher will only come at the agency's next meeting of member states' ministers in late 2012. If ESA signs a launch contract then, IXV could be ready to fly in the fourth quarter of 2013, Tumino said. "The objective now is to place the contract, build the vehicle and qualify it, then have it ready to be shipped to Kourou," Tumino said. "We really are now going to procure the contract for all the pieces necessary to run the mission. Now what we are missing at the next Ministerial [Council] is only the Vega launcher. We'll have all the pieces there to meet the launcher." Construction should begin in September, according to Tumino. The IXV program is emerging from a reorganization at the last Ministerial Council meeting in 2008. Italy increased their financial commitment to the project, and Thales Alenia Space of Italy was appointed prime contractor. An industrial consortium of EADS Astrium and Finmeccanica previously held the position. The reorganization "induced some delays" as Thales Alenia Space got up to speed on the program, but now the IXV is ready to enter the production phase, according to Tumino. Its mission will last just a few hours, but the IXV is a big step for Europe. The demo flight will not go into orbit, but the craft is a prototype for future vehicles that could service the International Space Station, land on other planets, or carry people to orbit. The IXV mission builds on years of ESA development, including the Hermes space plane program shelved by Europe in 1992. Hermes was supposed to be Europe's version of the space shuttle, conceived as a mostly reusable ship able to carry people back forth to orbit. Artist's concept of ESA's Hermes space plane. Credit: ESA But no Hermes shuttle was ever built despite considerable technological developments in the program. ESA's atmospheric re-entry demonstrator mission in 1998 proved out the Hermes flight control algorithms, but the IXV will fly with more a more advanced heat shield and working aerosurfaces. And it's shaped more like Hermes. The mission also recycles ESA's research for the NASA-led X-38 crew return vehicle, a lifeboat for the space station that was scrapped in the last decade. The IXV will fly with approximately 28 advanced ceramic heat shield tiles on its belly, while white ablative material will insulate the top of the vehicle during entry. With no wings and a peculiar blunt cigar shape, the IXV won't land on a runway like the space shuttle. Instead, the 16-foot-long ship will gently fall into the Pacific Ocean under a parachute, where it will be retrieved by the Italian Navy or a commercial vessel. There is no landing gear. But even without wings, the IXV is shaped as a lifting body, meaning it can maneuver in the atmosphere through a series of roll reversals. Movements of two electromechanical body flaps at the rear of the vehicle will steer the IXV during entry. It has a lift-over-drag radio of 0.7, giving the IXV "more controllability during flight, more maneuverability, and eventually a precision landing," Tumino said. The craft's shape means it flies through the atmosphere instead of falling like a capsule. Engineers are targeting an error ellipse of about 3 miles on the IXV mission, but follow-on vehicles could land with even more precision. "This is a demonstration mission. We will be launching from Kourou with a Vega launcher, and we have a set of ground segment stations which will support the mission," Tumino said. "Where the vehicle meets the atmosphere, the conditions will be equivalent to a return mission from low Earth orbit, so basically a 7.5 kilometers per second [16,777 mph] entry speed, so that we can experience all the key environmental features of such a re-entry mission." The craft's nose will pitch up 40 degrees during re-entry, and it will bleed off speed in a series of roll maneuvers like the space shuttle. Once officials wrap up contract negotiations this summer, some of their attention will turn to studying applications for the technology to be tested by the IXV. Tumino said the analysis will help prepare a proposal to ESA member states for the continuation of the program after the 2013 demo flight. "We see opportunities and the possibility to go into orbit and perform ground landings, so to have a retrievable and reusable system," Tumino said. "It's not the space shuttle, which has a huge cost because it's a huge system. It would have to be contained in cost so it would be affordable for Europe to pursue."http://www.spaceflig...ws/n1106/10ixv/

Edited August 13, 2011 by bigvlada

[bigvlada]

Hired private cargo ships booked to visit space stationBY STEPHEN CLARKSPACEFLIGHT NOWPosted: July 25, 2011 With the International Space Station stocked with food and clothing by the last space shuttle mission, SpaceX and Orbital Sciences are gearing up for test flights of their cargo freighters to the orbiting lab in December and February, government and industry officials said. Artist's concept of a SpaceX Dragon spacecraft approaching the International Space Station. Credit: NASA The commercial automated cargo vehicles are in the final stages of development and testing before moving to their launch sites in Florida and Virginia. NASA has "technically" agreed to combine SpaceX's next two demonstration flights of the company's Falcon 9 rocket and Dragon capsule, electing to send the next mission all the way to the space station, according to Bill Gerstenmaier, the head of the agency's human space programs. "We technically have agreed with SpaceX that we want to combine those flights, but we haven't given them formal approval yet," Gerstenmaier said last week. "We still want to go through some more analysis to go take and look and define exactly what criteria makes up that combined mission, what objectives are there, what the go/no go criteria is." The unmanned flight would blast off Nov. 30 from Cape Canaveral and reach the space station about one week later, where the lab's Canadian robot arm would reach out and grapple the approaching Dragon spaceship. SpaceX and NASA are reviewing plans for the mission, which would deliver some limited cargo to the complex. If everything goes as planned, SpaceX's first operational resupply flight would launch in the first half of 2012. Working under a funded Space Act Agreement with NASA, SpaceX tested the medium-lift Falcon 9 rocket on two flights in 2010. The second launch in December demonstrated the blunt Dragon capsule on two orbits around Earth, culminating in a successful splashdown and recovery in the Pacific Ocean. Under the initial agreement, SpaceX's next mission would have approached within the vicinity of the space station before backing away after checking out navigation and communications equipment. On the eve of the December flight, SpaceX asked NASA to accelerate the demo mission schedule and fly the next Dragon to the space station. "Overall, what we want to do is we want to get to cargo delivery as fast as we can, and if the systems are mature enough and the design is mature enough, combining those two flights is that best way to get cargo to ISS in the fastest manner possible," Gerstenmaier said. NASA added an extra space shuttle mission to haul food, clothes and other supplies to the station, putting the outpost on solid footing for more than a year even without further deliveries by NASA's budding commercial partners. Mike Suffredini, NASA's space station program manager, said the additional shuttle visit gives the agency wiggle room in case SpaceX and Orbital Sciences fall behind. The gear delivered by the shuttle Atlantis ensures the complex can remain at full operational capability through 2012. "This most recent space shuttle mission...was able to stock up the space station with supplies and consumables to buy some time for both us and SpaceX to get our cargo systems operational, but the pressure is on to get both of these delivery systems proven and into service over the course of the next year," said David Thompson, chairman and CEO of Orbital Sciences. Atlantis returned from the resupply flight July 21, wrapping up the shuttle program's 30 years of service. File photo of the International Space Station. Credit: NASA Speaking to reporters after the shuttle's last landing, Gerstenmaier said NASA is analyzing SpaceX's flight software using Monte Carlo methods. SpaceX's flight design for the mission is also being reviewed, particularly regarding two small Orbcomm communications satellites to be carried as secondary payloads on the mission. The first and second stages of the Falcon 9 rocket for SpaceX's cargo flight are already at the company's Cape Canaveral launch pad. The Dragon spacecraft is due to arrive in August or September. "We're doing all the planning to go ahead and combine those missions," Gerstenmaier said. "The capsule is being designed that way and the software is being built that way, and we're just kind of waiting for the right formal time where we collectively agree that this is the right thing to go forward." Two months after SpaceX's first mission to the space station, Orbital Sciences plans to launch its inaugural Cygnus resupply ship. The company foresees the mission launching in February 2012, according to Thompson. SpaceX and Orbital's missions will fly to the space station soon before or after European and Japanese cargo freighters dock to the outpost. Orbital Sciences holds a $1.9 billion Commercial Resupply Services contract with NASA to serve the International Space Station with eight flights of the Taurus 2 rocket and the robotic Cygnus cargo freighter. The contract requires Orbital to deliver 20 metric tons, or about 44,000 pounds, of equipment to the complex over the eight missions. SpaceX signed a similar contract worth $1.6 billion for 12 flights of the Falcon 9 rocket and Dragon capsule. Both companies have Space Act Agreements, funneling government financing to help design, build and test commercial spacecraft for cargo resupply missions to the space station. The NASA funding is coupled with private investment. The public-private partnership is called the Commercial Orbital Transportation Services, or COTS, program. Orbital Sciences will launch the Cygnus spacecraft on the Taurus 2 rocket from a new pad at Wallops Island, Va. Delays in installing and checking out the Wallops launch complex's propellant and pressurization systems has pushed back the Taurus 2 rocket's debut flight from October to December, Thompson said July 21. The launch pad should be completed in August, and a pathfinder version of the Taurus 2 rocket will be moved to the complex in October. The December test launch was added with the help of NASA funding to reduce the risk in Orbital's rocket and spacecraft development programs. If the launch is successful, Orbital aims to bolt the first Cygnus craft to the second Taurus 2 rocket for liftoff in February. Artist's concept of a Taurus 2 rocket launch. Credit: Orbital Sciences Thompson said a failure during a June ground test of Aerojet's kerosene-fueled AJ26 engine is also unlikely to cause any significant delays in the Taurus 2 launch manifest. Each Taurus 2 rocket first stage is powered by two AJ26 engines, which were built in Russia for the Soviet Union's moon program in the 1960s and 1970s. Aerojet acquired and modified the engines for U.S. launches. "Orbital, Aerojet and NASA have substantially completed our analysis of the cause of this test failure and have developed a screening process which is now being applied to an initial batch of the three dozen or so AJ26 engines that are in inventory at Aerojet," Thompson said in a conference call with financial analysts. Thompson said about two-thirds of Aerojet's AJ26 inventory are ready for flight as is, with the remaining engines needing "some level of rework or repair" before being cleared for launch. The June testing mishap occurred at NASA's Stennis Space Center in Mississippi. The AJ26 engine caught fire after a leak in one the powerplant's fuel lines. According to Thompson, two Taurus 2 first stages built in Ukraine are already at the Wallops launch site. One solid-fueled Castor 30 second stage motor is also now at Wallops. The Cygnus mass simulator and instrumentation package that will fly on the Taurus 2 rocket's December test flight has also been shipped to the coastal Virginia launch site.http://spaceflightnow.com/news/n1107/25cotsdemo/Ovde je jedan interesantan problem u nastajanju, višak kapaciteta u pogledu teretnih brodova a manjak u slučaju onih koji treba da prevoze posadu

[bigvlada]

NASA agrees to help modify Atlas 5 rocket for astronautsBY STEPHEN CLARKSPACEFLIGHT NOWPosted: July 19, 2011 United Launch Alliance and NASA will share technical data to help ready the company's Atlas 5 rocket for astronaut passengers, officials announced Monday. Artist's concept of an Atlas 5 rocket launching Sierra Nevada's Dream Chaser space plane from Cape Canaveral, Fla. Credit: Sierra Nevada The agreement places the Atlas 5 rocket among the top competitors to launch the next piloted spacecraft from U.S. soil after the retirement of the space shuttle. "I am truly excited about the addition of ULA to NASA's Commercial Crew Development program team," said NASA Administrator Charlie Bolden. "Having ULA on board may speed the development of a commercial crew transportation system for the International Space Station, allowing NASA to concentrate its resources on exploring beyond low Earth orbit." Colorado-based United Launch Alliance was passed over in NASA's last Commercial Crew Development, or CCDev, competition. When the agency announced the winners in April, officials said they gave priority to spacecraft developers because rockets would take less time to modify for manned flights. NASA divided $270 million among four companies in the April announcement, giving $92.3 million to Boeing, $80 million to Sierra Nevada Corp., $75 million to SpaceX and $22 million to Blue Origin. The competition was the second round of NASA's CCDev program, which provides federal funding to U.S. space companies building commercial human-rated spacecraft. All of the winners are designing spacecraft to carry astronauts to and from low Earth orbit destinations such as the International Space Station. But the space vehicles will need rockets to send them into orbit. Boeing, Sierra Nevada and Blue Origin could launch their spacecraft on ULA rockets. Sierra Nevada and Blue Origin have selected the Atlas 5 rocket to launch their spaceships. Sierra Nevada is working on a lifting body space plane named the Dream Chaser and Blue Origin, headed by Amazon.com founder Jeff Bezos, is developing a biconic capsule called the New Shepard. Artist's concept of an Atlas 5 rocket with Boeing's CST-100 capsule. Credit: Boeing Boeing's CST-100 spaceship is designed to ferry up to seven astronauts to and from orbit. The company says the craft is compatible to launch on several rockets, including the Atlas 5, but managers plan to select a primary launch vehicle in the coming weeks, according to a Boeing spokesperson. Boasting a stellar success record, the Atlas 5 rocket has launched 26 times with U.S. military payloads, NASA science probes and commercial communications satellites. The Atlas 5's first stage is powered by a kerosene-fueled Russian RD-180 main engine, and its Centaur second stage features one or two RL10 engines burning cryogenic propellant. SpaceX will launch its Dragon capsule on the company's own Falcon 9 rocket. NASA's agreement with ULA doesn't provide any funding, but it facilitates data sharing among the two entities. Under the agreement, ULA will provide technical data on the Atlas 5 rocket to NASA, which will give input based on the agency's extensive human spaceflight experience. The space agency will also share draft human-rating certification requirements for ULA to review and provide feedback. ULA says it will continue design and analysis of its plans to outfit the Atlas 5 for human crews, conduct program reviews, develop a hazard analysis, complete a probabilistic risk assessment, conduct a systems requirements review, and accomplish several other milestones. The company will pay for the continued design work without any NASA money. File photo of an Atlas 5 rocket launching NASA's Solar Dynamics Observatory in February 2010. Credit: Pat Corkery/United Launch Alliance NASA awarded ULA $6.7 million in the first CCDev competition in 2010 to advance the development of an Emergency Detection System, a computer that would monitor the health of rocket and spacecraft systems during launch. The system would issue commands for an abort to send astronauts away from a failing rocket. The $6.7 million agreement expired at the end of 2010. "This unfunded [space Act Agreement] will look at the Atlas 5 to understand its design risks, its capabilities, how it can be used within the context of flying our NASA crew and maturing ULA's designs for the Emergency Detection System and launch vehicle processing and launch architectures under a crewed configuration," said Ed Mango, NASA's commercial crew program manager. ULA says the EDS computer is the only significant modification necessary for the Atlas 5 rocket to meet human-rating requirements. Other launch pad construction would be necessary to support crew launches, according to George Sowers, ULA's vice president of business development. "We believe this effort will demonstrate to NASA that our systems are fully compliant with NASA requirements for human spaceflight," Sowers said. "ULA looks forward to continued work with NASA to develop a U.S. commercial crew space transportation capability providing safe, reliable, and cost effective access to and return from low Earth orbit and the International Space Station."http://spaceflightnow.com/news/n1107/19ulaccdev/Ovo je dobar korak, tržište će se za nekih petnaestak godina profilisati na one koji nude rakete, kosmodrome za turiste, kosmodrome za ljudske posade i teretnjake, proizvođače teretnih letelica i proizvođače letelica(uglavnom kapsula) za posade. Jednostavno, niko neće imati novca da sve sam razvija a svima će biti u interesu da njihova raketa može da opsluži širok spektar letelica ili da njihova letelica može biti lansirana uz pomoć cele game raketa.

[Tale]

Od ove valjda nema niže orbite:UARS Live Tracking

[bigvlada]

SpaceX unveils flyback Falcon rocket reusability planBY WILLIAM HARWOODSTORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSIONPosted: September 30, 2011 SpaceX founder and chief engineer Elon Musk, speaking at the National Press Club Thursday, unveiled an innovative plan to recover his company's spent rocket stages by flying them back to the launch site using their own engines for a powered vertical descent to touchdown on strut-like landing gear. If the system works, Musk said, launch costs would be dramatically reduced. http://www.youtube.com/watch?v=0H_cjfk5v1k&feature=youtu.be "It's just a very tough engineering problem," he said. "(But) I've come to the conclusion that it can be solved. And SpaceX is going to try to do it. "Now, we could fail. I'm not saying we are certain of success here, but we are going to try to do it. We have a design that on paper, doing the calculations, doing the simulations, it does work. Now we need to make sure those simulations and reality agree because generally, when they don't, reality wins." All currently flying orbit-class rockets are known as expendable launch vehicles because their stages simply fall into the ocean or burn up in the atmosphere after boosting satellites and other payloads into space. NASA's space shuttle was partially reusable in that the orbiter itself and its two-solid-fuel boosters were recovered after launch. But launch costs remained high for a variety of reasons and in any case, the shuttle is no longer flying. SpaceX holds contracts to build and launch unmanned supply ships to the International Space Station using the company's two-stage Falcon 9 rocket. The company also is in the second phase of a NASA program to develop a manned version of its Dragon capsule as a possible commercial endeavor. Recovering the Falcon 9 first stage for refurbishment and reuse has been a long-standing goal for SpaceX, but the plan unveiled Thursday goes far beyond the parachute recovery previously envisioned. In a dramatic video animation (posted above), a Falcon 9 rocket is shown blasting off from Cape Canaveral, Fla. After separating from the second stage, the first stage flips about to put its engines in the direction of travel, three of the nine powerplants re-ignite to slow the booster, which then deploys three folding landing struts to make a vertical landing on a concrete pad. In similar fashion, the second stage flips about after deploying its payload, fires its engine to drop out of orbit and then flips around again, re-entering the atmosphere head first, protected by a heat shield at the top of the stage. Once out of the high-speed, high-heating zone, the second stage would flip around again for a powered descent to touchdown. SpaceX already plans for the manned version of its Dragon capsule to make a similar powered descent. "We'll see if this works," Musk said. "But it's going to be certainly an exciting journey. And if it does work, it'll be pretty huge. If you look at the cost of a Falcon 9 ... it's about $50 (million) to $60 million. But the cost of the fuel and oxygen and so forth is only about $200,000. So obviously, if we can reuse the rocket, say, a thousand times, then that would make the capital cost of the rocket for launch only about $50,000. ... It would allow about a hundred-fold reduction in launch costs." Musk said designing and building the recovery systems will not slow down work on the company's manned spacecraft or unmanned cargo ships and that development will be carried out in parallel. SpaceX currently is gearing up to launch its first unmanned cargo craft to the International Space Station following a generally successful test flight last year. Liftoff of the upcoming flight had been planned for Nov. 30, but Musk said the recent failure of a Russian Progress supply ship, and subsequent delays for Russian manned missions, likely would push the SpaceX launch into January.http://spaceflightno...0spacexflyback/Jako interesantna ideja, koja do sada nije pokušana.Ako im ovo uspe (a ovo je veliko ako) cena lansiranja jednokratnih raketa će dramatično pasti (recimo da u svakom tenutku imaju pet raketa u različitim fazama čišćenja i pripreme za let a da im to bude dovoljno za lansiranje 100 satelita). Definitivno uzbudljivo vreme.

Edited October 11, 2011 by bigvlada

[bigvlada]

Prilikom opisivanja Deus Ex-a, pominjao sam x-37b otv-1. Evo kako izgleda letelica kao i njena buduća C varijanta koja bi mogla da nosi do 6 putnika. Ima male dimenzije, dva komada bi mogla da stanu u odeljak za prtljag šatla. Sovjeti su imali par projekata mini šatlova sličnih dimenzija, lks i molniju.

[bigvlada]

Kratak pregled ISS-a

[bigvlada]

Foto galerija spremanja Delta 2 rakete za lansiranjehttp://spaceflightnow.com/delta/d357/flow/

[hazard]

nego bigvlado, zar nije definicija niske orbite do 2000 km? Tebi u podnaslovu stoji 35000 km

[bigvlada]

Niska, manja od geostacionarne (35.876km). Sve ispod toga je LEO (low earth orbit) a zaokružio sam na 35.000 da ljude ne bi zbunjivao broj. :)Imaš i GTO (Geostationary transfer orbit) gde je apogej sličan GSO a perigej mnogo manji, 200-300km. Koristi se za lansiranje nekih satelita koji onda sopstvenim pogonom odlaze i parkiraju se na GSO. To se radi kada se želi da se uštedi na raketi nosaču ali onda satelit nosi manje goriva za kasnije manevrisanje i manje instrumenata radi dodatnog goriva koje će ga doneti i parkirati na toj većoj visini.

[bigvlada]

izvini na trolu, nisam bas pratio forum poslednjih nedelja : jel pominjano na forumu da je sojuz u prosli cetvrtak poleteo iz francuske gvajane? eej, to je bre vest!

Photos: Soyuz blasts off from French Guianahttp://spaceflightnow.com/soyuz/vs01/launchphotos/

[bigvlada]

Kao update jednog PM-a, na ovoj slici se vidi glavna razlika između sovjetskog i zapadnog modela lansiranja raketa. USA i EU rakete sklapaju vertikalno, tj. na prvi stepen se stavlja drugi, eventualno treći i onda koristan teret. Rusi sve sklapaju horizontalno. Oba pristupa su podjednako dobra ali svaki ima i probleme. Kod uspravnog načina najkritičniji momenat (koji može da potraje) je pomeranje te skalamerije od zgrade gde je sklapana do lansirne rampe (zamislite koliko je trajalo pomeranje Saturna V ili Šatla do rampe). Kod rusa je podjednako nepriajtan problem, jer raketa može da se ošteti prilikom uspravljanja. Ipak, pošto je to mnogo manji rizik od onog šetanja nečega visine solitera po vetru, moj glas ovde ide horizontalnom sklapanju, šinskom transportu i kasnijem podizanju. U oba slučaja, tek kada su rakete uspravno na rampi može se pristupiti probama s punjenjem i pražnjenjem goriva. Edited November 15, 2011 by bigvlada

[hazard]

Kako mocno izgleda ova raketa u ovom polozaju :) pravi filmski kadar :)

[Skyhighatrist]

nego bigvlado, zar nije definicija niske orbite do 2000 km? Tebi u podnaslovu stoji 35000 km

Niska, manja od geostacionarne (35.876km). Sve ispod toga je LEO (low earth orbit)

Hm, i ja imam blagi problem sa "zaokruživanjem" odnosno "združivanjem" niske i srednje orbite...Samo da budemo precizni za one koji cene preciznost: :) Niska orbita (LEO) - do 2000 kmISS je na 340km, Mir je bio na 390, a Hubble je na 600 km.Srednja orbita (MEO) - od 2000 do 35.786Otprilike na polovini (oko 20k km) ove orbite su GPS sateliti (SSO - Semi synchronuos orbit), koji obilaze oko zemlje tačno na 12 sati, a na 35.786km su geosinhroni, i geostacionarni sateliti (GEO i GSO), koji kruže oko Zemljine ose brziom rotacije Zemlje, pa su posmatrano sa površine - nepomični (u slučaju geosinhronih satelita - relativno nepomični). Tu su praktično svi telekomunikacioni sateliti, tako da su antene uvek usmerene u jednu tačku. U protivnom, stalno bi antenama "jurio" satelite.Visoka orbita (HEO) - Sve preko 35kEdit: wiki (naravno) ima i sličicu:LEO - svetlo plavaISS - isprekidana crvenaMEO - žutaGPS sateliti - isprekidana zelenaGEO - isprekidana crnaHEO je sve preko GEO Edited November 16, 2011 by historian

[bigvlada]

Hm, i ja imam blagi problem sa "zaokruživanjem" odnosno "združivanjem" niske i srednje orbite...

Ma jednostavno, sve što ne stoji u mestu u odnosu na posmatrača na zemlji je "niska" :) Lakše mi je bilo da zaokružim na 35.000 jer i kada se navode karakteristike raketa stavlja se samo koliko mogu da ponesu u nisku orbitu a koliko u geostacionarnu, ostale se retko pominju. Lepo se potrefilo da mogu da ilustrujem i drugi primer. NASA pomera mobilnu lansirnu rampu do lansirnog kompleksa 39b (bivši šatlov). Vidi se gmizavac po kome se sve to prenosi.