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The (currently only) answer to Why did Sputnik 1 have four antennas? discusses how Sputnik 1 had four antennas in order to ensure that the Earth would never be in the null of any of its antennas.

PearsonArtPhoto's answer specifically states that

[Sputnik] 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.

This would seem to beg the question, did Sputnik 1 have any attitude control at all? (By means of thrusters or otherwise.) Or was it simply tumbling along in its orbit in whatever attitude and roll rates it happened to end up in after booster separation?

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    $\begingroup$ Forgive my ignorance.. is attitude different from altitude? $\endgroup$ – Zaid Oct 15 '16 at 10:01
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    $\begingroup$ @Zaid Attitude is the direction something is facing. An attitude control system is a system which makes sure a spacecraft points in the right direction. Altitude is how high up something is. $\endgroup$ – Philipp Oct 15 '16 at 11:16
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    $\begingroup$ @Zaid Philipp is correct. In general, if you are curious about a term, try hovering over the relevant tag. In this case, the "attitude" tag is briefly described as being used for "Questions on ascertaining, predicting, and controlling spatial orientation and rotation of spacecraft, and on forces that affect spatial orientation." $\endgroup$ – a CVn Oct 15 '16 at 11:23
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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

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  • $\begingroup$ One of the missions of Sputnik was to observe its interactions with the atmosphere. While the atmosphere is very thin, it is not completely absent. Did it really just "tumble" or would it have eventually "stabilized" with the antennas trailing the sphere due to the center of pressure being behind the center of mass (presumably)? $\endgroup$ – Steve Oct 14 '16 at 20:57
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    $\begingroup$ @Steve, I'm not certain that part of the mission was dependent upon the antennas. From everything I understand (and I am not any kind of engineer, so this is intuition, not calculation), the antennas would not have caused sufficient drag to affect the attitude. The affect on attitude would have been observed from watching how slowly or quickly drag affected the orbit of the satellite. $\endgroup$ – Justin Eiler Oct 14 '16 at 21:16
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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 batteries, 2 connected to the radio and one to the thermal control system. There was no power left over for other systems to interface with it.

For reference, the upper stage of Sputnik 2 did have an attitude control system, basically a "cold gas" system to maintain stability, although Sputnik did not.

Other early systems basically were spin stabilized if stabilized at all. I can't find the first reference to a fully stable satellite, but I'm sure it happened quite early.

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