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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 ...


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 ...


24

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'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.


18

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 ...


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 ...


16

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 ...


15

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, ...


12

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


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 ...


9

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 ...


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.


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 ...


7

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 ...


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 ...


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

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 ...


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 ...


2

The flux values of the charged particles radiation vary heavily depending on position within the Van Allen belts and are influenced by solar storms. At the magnetic equator, electrons of energies exceeding 5000 keV (resp. 5 MeV) have omnidirectional fluxes ranging from 1.2×10^6 (resp. 3.7×10^4) up to 9.4×10^9 (resp. 2×10^7) particles per square ...


2

The following is (now apparently disproven) speculation based on some very basic radio theory rather than any particular knowledge of Sputnik 1. It should be disregarded if someone with knowledge of the actual circuits in use has better information. I did some web searching but did not find any descriptions of Sputnik 1 that provided good evidence for or ...


2

https://www.roscosmos.ru/24173/ The main tasks of the satellite were: verification of calculations and basic technical decisions made for launch; ionospheric studies of the passage of radio waves emitted by satellite transmitters; experimental determination of the density of the upper layers of the atmosphere by deceleration of the satellite and ...


1

There were a few things that were done, namely: A number of news articles. Events at planetariums Events at the Smithsonian/ other museums I'm sure there were other events too, but I can't find references. I can't find any in Russia itself, interestingly enough.


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