the mission of Kosmos 21 Options

[Paolo]

Hi all
I just finished reading Bart Hendrickx's "Managing the News: Analyzing TASS Announcements on the Soviet Space Program (1957-1964)" in the latest issue of Quest and there are a few sentences that sound new to me.
Apparently, the 3MV flights to Venus and Mars of 1964 would be preceded by two Zond test flights that would insert probes in Earth-like orbits inclined 5 degrees to the ecliptic (quite a large inclination, by the way), testing the re-entry of the atmospheric capsules 6 months after launch, when the orbit of the probes would again intersect the path of Earth.
The first such flight was launched on 11 November 1963 and never left Earth orbit, becoming known as Kosmos 21. The second probe was launched unsuccessfully on 19 February 1964 on a "deep space mission that would not bring it back to Earth". Other sources describe it as a Venus flight, launched at the opening of the 1964 launch window.
I had never heard of such test flights, in fact all the sources I have identify Kosmos 21 as a failed lunar flyby "à la Zond 3", but on the other hand, it is described as a 3MV-1A probe, that is similar to Zond 1 (a 3MV-1), which indeed carried a descent capsule. Also, the reason for the second probe only being launched months later puzzles me: the Earth-return window closed on 19 November. I thought these Earth-return flights could be launched more or less year-round. But maybe this has something to do with constraints such as a northern hemisphere landing in daylight and with favorable weather.
Anyone has other reliable sources on the objectives of these missions? I have not had the time to check what Chertok has to say about them. Also, was Kosmos 21 launched during a Moon launch window? and was the Venus launch window already open when the second 3MV-1A left Earth?
Also, speaking of the 1964 Mars shots, the article states that "ground-based studies of Mars determined that the planet's atmosphere was much thinner than expected, making it necessary to modify the design of the landers". However, due to OKB-1 being busy with other, higher priority missions (mainly Voskhod), "it was decided instead to launch a 3MV test probe in the direction of Mars and attempt to deliver a pennant to the Martian surface without actually conducting scientific studies". This is said to have been the attempted objective of Zond 2. This again puzzles me, as it has been more or less established that Zond 2 was a 3MV-4 probe twin of Zond 3, i.e. carrying a photographic payload. Any thoughts on tihs?
BTW kudos to Bart, it was a very entertaining and informative article to read!
Paolo

[Paolo]

a few links if you wish to follow this small historical mystery:

http://www.friends-partners.org/pipermail/...ber/031242.html
http://www.friends-partners.org/pipermail/...ber/031245.html
http://www.friends-partners.org/pipermail/...ber/031253.html
http://www.friends-partners.org/pipermail/...ber/031256.html

http://forum.nasaspaceflight.com/index.php?topic=29821.0

http://www.novosti-kosmonavtiki.ru/phpBB2/...pic.php?t=13205