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In The Century of Space Science, edited by J.A. Bleeker, Johannes Geiss, M. Huber, viewed in Google books I ran across the following text and images.

Both satellites are quite stylish looking and have very pronounced alternating white and black stripes.

Presumably the satellites would not be exposed until they are in space when the fairing or nose cone can open, so they would be too far away to see clearly in a telescope so that rotation or tumbling would be visible.

Question: Why were Europe's first few satellites so stylish? Why did they have very pronounced alternating white and black stripes, and had Vanguard-like antennas, but not its shiny reflective metallic finish1,2.


From pages 52 and 53:

France's Astérix was a 42 kg test satellite

The fruits of these investments were soon to be seen. On 26 November 1965, a Diamant rocket rose from the Hammaguir launch pad and placed into orbit the first French satellite, significantly called Astérix. France thus became the third space power and confirmed its claim for an independent role in this important strategic field.

Astérix was a 42 kg test satellite whose role was to confirm the rocket’s ability to place it into orbit. Ten days later, on 6 December 1965, an American Scout rocket launched France’s first scientific satellite, FR-1. This satellite, weighing 60 kg, had been developed by CNES and carried instruments for studying ionization irregularities in the ionosphere and the magnetosphere. It was launched from Vandenberg and placed into a near-circular orbit.


Italy's San Marco-1 satellite

Broglio was quick to react to NASA’s offer of collaboration in space research. In 1962, Italy and the USA signed an agreement for the so-called ‘San Marco’ project, and two eyars later, on 15 December 1964, the first Italian satellite, San Marco-1, was launched by a Scout rocket from Wallops Island. It was a sphere with a diameter of 66 cm and weighed no less than 115 kg. Built by the University of Rome’s Centro di Ricerche Aerospaziali under the direction of Broglio, this was the first all-European satellite to circle the Earth. A second San Marco satellite was launched by Broglio’s group in 1967 from a platform anchored in the Indian Ocean off the coast of Kenya, and the programme continued in the following decade.

1Puzzler: Is this a Sputnik?

2This BBC photo does not show a replica of Vanguard-1, what might it be?

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    $\begingroup$ Possibly related: space.stackexchange.com/q/37554/6944 $\endgroup$ – Organic Marble Sep 4 at 14:40
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    $\begingroup$ Related fact: Tracking of space objects is often done with optical telescopes example, this was partially done to prevent unidentified space objects from triggering missile alerts. When SACI-1 failed first contact, is was possible to identify that the panels had opened and the umbilical cable had been properly cut. $\endgroup$ – Mefitico Oct 24 at 20:22
  • $\begingroup$ @Mefitico those links are compelling, but how are they related to this question post exactly? I'm missing the context. These may also be of interest: What would be a “big picture” understanding of how the orbits of Earth satellites are monitored? and also Is there a satellite that tracks other satellites? $\endgroup$ – uhoh Oct 25 at 0:41
  • $\begingroup$ @uhoh I had a gut feeling about the answer, and planned to add one more reference, claiming this satellite was meant to validate the launcher only here, but only found it in French. It has telemetry recorders on-board, but the transmission antennas failed (which engineers likely had foreseen). In the end, I was left with only the first intended comment, and lacked both good references and evidence pieces to reach any conclusion. $\endgroup$ – Mefitico Oct 25 at 2:52
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    $\begingroup$ @uhoh: My guess is: The stripes are made for facilitating identification and assessment of the spacecraft attitude via optical telescopes. Radars work only for orbit, but they might confuse satellites with similar orbits and radar cross-section. Also, because it is an early experiment, both the injection orbit could be off-target and the antennas could have broken, making the telescope assessment a backup method. The lines are around the spin axis and large enough to differentiate at the perigee, but I'm missing a lot of research to uphold those claims. $\endgroup$ – Mefitico Oct 25 at 4:10
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To address only Astérix: Space Archaeology has a different picture and a writeup:

enter image description here

Weighing 42 kilograms, the satellite was a distinctive striped fibreglass spinning-top shape half a meter in diameter, the black stripes to provide passive thermal control.

I suspect the picture is of a replica, and this is not a primary source, but maybe it'll do until something better comes along.

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  • $\begingroup$ "Thermal regulation" is always the throwdown answer! I too would like to see more detail. $\endgroup$ – Organic Marble Sep 4 at 22:21
  • $\begingroup$ Nice find, thank you for posting! Now that we can see that the surface (at least of this likely replica) looks more like brushed metal than white paint, the surface looks much more like the other early satellites, but I don't see any of those reflections in the poor reproduction in the question, so we can't be sure yet I guess. The dark areas will absorb heat from the Sun more rapidly, but radiate it back into space more rapidly as well, so I'm not sure what the net effect will be on the spacecraft's temperature as it passes in and out of the Earth's shadow. Cool problem (pun intended). $\endgroup$ – uhoh Sep 4 at 23:55

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