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74

Laika's magical mystery propellant was kerosene and LOX. Sputnik 2 was launched on the 8K71PS launcher. This was a modified R-7 ICBM, and like all the R-7 derived launchers, its RD-107 and RD-108 engines burned kerosene/LOX. The Russian specification for rocket-grade kerosene is called RG-1, and it's similar to the American RP-1. The specific impulse of ...


45

Shot answer: Was Sputnik-1 "only for beep" - no, it wasn't :) It was technical test of R-7 as space launcher and test of spacecraft in orbit (athough very simple spacecraft). Also scientists at least tried to make atmosphere research with Sputnik-1. (From my current search results I'm not sure they got much.) Long answer: It's current state of my ...


39

From this pdf (Reconsidering Sputnik: Forty Years Since the Soviet Satellite) at NASA.gov referring to Sergei Korolev, the lead rocket engineer for the Sputnik project: There were many debates on the shape of the first satellite, with most senior OKB-1 designers preferring a conical form since it fit well with the nose cone of the rocket. At a meeting ...


31

I don't know what the USSR was trying to do with it, but I know what the US Navy did with it. Researchers at the Johns Hopkins University's Applied Physics Lab used the Doppler shift on the 20 MHz tone to determine Sputnik-1's orbit, plus ionospheric electron density and a couple of other things (like a transmitter frequency offset of ~1 kHz from the ...


27

Sputnik 1 was pressurized with nitrogen at 1.3atm. The period of the beeping was tied to a pressure sensor. The logic was being that if anything (such as a micrometeoroid) penetrated the satellite, the change in pressure would detect this and inform the scientists on the ground. This simple test had scientific value for the later programs with living samples ...


25

The important number here is the perigee, not the apogee. In order to make this amount of orbits, you need to have a certain height of perigee in the order of 200 to 300 km. A circular orbit of 250 x 250 km would certainly have sufficed their needs. But: The important word here is 'circular': You can't get directly into a circular orbit. After launch you'...


22

Sputnik-1, and Sputnik-2, had no attitude control whatsoever, and would have tumbled freely. "[Like] its predecessor, Sputnik-2 would have no attitude control system." http://www.russianspaceweb.com/sputnik2_decision.html Sputnik technical specifications and diagram: http://www.russianspaceweb.com/sputnik_design.html


19

I'm sure it could have been done somewhat earlier, but there was still quite a big technical step between the suborbital sounding rockets / short-range ballistic missiles derived from the V-2, and a multi-stage, high performance vehicle capable of orbit. Advances in guidance systems were definitely necessary, but I think raw performance in terms of delta V ...


19

I've tried to write it down, but then I've changed it into the following scheme. That way it is much cleaner. Note that the scheme doesn't include the recent Soyuz-2.1v vehicle. It seems like it is not "based" on R7 anymore. The conic boosters and core stage of R7 are no longer present.


17

No, Sputnik did not have any such system. It would have added complexity and power requirements. The Soviets were trying to beat the Americans in to space, and succeeded by the launch of Sputnik, but they had little time to design it well. There were basically 3 systems in the spacecraft, radio, power, and thermal management. The power was mostly 3 ...


16

I think @PearsonArtPhoto 's answer misses several major points. From http://www.cs.mcgill.ca/~rwest/link-suggestion/wpcd_2008-09_augmented/wp/s/Sputnik_1.htm The satellite carried two antennas designed by the Antenna Laboratory of OKB-1 led by M.V.Krayushkin. Each antenna was made up of two whip-like parts: 2.4 and 2.9 meters (7.9 and 9.5 ft) in length, ...


16

Sputnik was the first satellite. It was set up before we had an understanding of how difficult it would be to maintain a satellite's position, and in fact was a very simple system overall. The 4 antennas gives an omnidirectional broadcast pattern. The simplest form of an antenna, a dipole, has two beams going in opposite directions. It's beam pattern looks ...


12

I found a photos, after searching around a bit. I haven't found any video yet. See Space.com for more.


11

Sputnik had just one single job: Prove its existence by sending a simple "beep" regularly (about 2-3 times a second, afaik). It was a single radio signal. There was no problem with radiation, the satellite is just too simple to have problems with radiation.


11

Yes, there are videos of the launch of Sputnik 1, there was no way that the Soviet propaganda machinery of those times would have missed the opportunity, and I've seen at least two separate sources, one filmed on a color camera, and another black & white from a slightly different angle. From what's available online, sadly none are of quality we've ...


10

The RAND Corporation issued far-seeing reports on artificial satellites as early as 1946 (http://www.rand.org/pubs/special_memoranda/SM11827.html) - a must read! There was no immediate military need to develop satellites right then, so the whole agenda lingered on. Von Braun was directed by the Army to focus on intermediate-range missiles, and the Air Force ...


9

Sputnik-1 had initial orbit with 950 km apogee an 220 km perigee. It was planned to have 1450 km apogee but the rocket underperformed slightly. 950 km is far from most intensive radiation belts. Also, Sputnik-1 only operated for 22 days before its batteries ran out. So it probably hadn't enough time to suffer significant radiation damage. Remark: initially ...


8

As @Uhoh answered in comments: * The Wikipedia article about Laika says: "Over five months later, after 2,570 orbits, Sputnik 2—including Laika's remains—disintegrated during re-entry on 14 April 1958." For basic historical questions like this, it's always worth looking at Wikipedia first, and then coming here if you cannot find the info you need.


8

Sputnik-1 was political statement. Its science value was close to zero. Some see the entire Space Race as a series of political statements: “If we can do this, think of what we can do to your cities.” A rocket capable of putting a satellite into orbit, even a small one such as Sputnik-1, is more than capable enough to deliver a nuclear bomb to ...


8

Looks like the first Soviet satellite with solar power capability was Sputnik 3, launched on the 15th May 1958, losing out to Vanguard 1 which was the first satellite with solar power launched only two months earlier. Of Sputnik 3, Wikipedia says It was powered by silver-zinc batteries and silicon solar cells which operated for approximately 6 weeks From ...


7

You have to remember that technology was much less advanced at the time of Sputnik 1. It’s ability to downlink information was tiny, and the science was organized around that: The ball was pressurized, and the skin and internal temperatures were (the only?) quantities downlinked. This was used to put a lower limit on micrometeoroid impact rate, as a leak ...


7

After reaching orbit the nose cone was jettisoned successfully but the Blok A core did not separate as planned. This inhibited the operation of the thermal control system. Additionally some of the thermal insulation tore loose so the interior temperatures reached 40 C. It is believed Laika survived for only about two days instead of the planned ten because ...


6

Humans have passed through the Van Allen belts and lived, but you know that. The outer belts are the highest radiation ones, and those are out beyond the ~1600km maximum of the Sputnik 2 orbit. From a Applied Physics Lab document I get an average radiation dose of the Van Allen belts (unspecified inner or outer) of 50Gy/year. Taking a full 10 days of ...


5

Russian version of Sputnik-1 Wikipedia article has the section labeled "Sounds of Sputnik" and cites the respective technical report regarding development of the Sputnik's "radio device" D-200 (in Russian). According to the report, primary reason for transmitting on two frequencies was redundancy. The transmission frequency had to be ...


5

Elliptical orbit for Sputniks was chosen because it was easier to achieve, i.e a single burn was reqiured instead of utilising the need for the second burn for the orbit circularization. Note (as also mentioned in the other answer) that the "second stage" of R7 rocket was ignited together with the four boosters at liftof, and also Sputnik-1 was the third ...


5

Both internal pressure and temperature of Sputnik 1 were encoded in the radio signal. Analysis of the radio signals was used to gather information about the electron density of the ionosphere. If the temperature exceeded 50 °C (122 °F) or fell below 0 °C (32 °F), another control thermal switch was activated, changing the duration of the radio signal pulses.[...


4

The main reason for that delay from early rockets to orbit-capable rockets is known as the rocket equation: https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation In layman's terms, the faster you want a rocket to go, the more fuel it requires. The fuel increases the weight, requiring larger engines, and yet more fuel. To achieve orbital speeds, ...


4

First off, Sputnik 1 was when space travel went from being "just a theory" to being an actual thing. The difference is huge, do you not see a lot of theories about future technologies here and there? Can all of them be true? No matter people where sceptical to the concept of space travel. Secondly, the successful launch saved Korolev's ass. The head ...


4

After the fact, yes, Sputnik 1 had some scientific value. But all it did was beep. That is a fact. It had no scientific payloads. No matter how much one sugarcoats the after the fact scientific discoveries inferred from Sputnik-1's orbit, the fact is that the Soviet Union intentionally stripped Sputnik-1 of all of the scientific instruments that the USSR ...


3

It appears to just be a carrier signal alternately transmitted and not transmitted. As the carrier is in the MHz range, the audio cannot be a direct mapping of that frequency. I don't know the specific mechanisms used to make the signal audible as a particular tone, or whether that tone would differ between different receivers. There are multiple ...


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