First of all, many thanks to list members who replied to my recent
query about the configuration in orbit of the aerials on the Sputnik 1
satellite. Since then, I ran across a number of interesting references
with information pertinent to my query. These are Robert Godwin's book
"Russian Spacecraft" (an Apogee Books Pocket Space Guide), Michael
Lennick's book "Launch Vehicles: Heritage of the Space Race" (another
Apogee Pocket Space Guide), and Asif A. Siddiqi's mammoth tome
"Challenge to Apollo: The Soviet Union and the Space Race, 1945–1974."
This latter, more than a thousand pages long, must qualify as THE
definitive study of the USSR space program and should be required
reading for anybody interested in the history of the world's space
programs. Between these references and what I've picked up from "Space
Log," this list, and the Internet, I think I know Sputnik 1's antenna
configuration in orbit. I'd appreciate any and all comments on and
corrections to the following.
First of all, any illustration of Sputnik 1 in orbit that shows
aerials extending radially outward from an "equator" is certainly
incorrect. The four aerials were attached tangentially to the
spherical surface at a "latitude" of about 35 degrees, that is, evenly
spaced in a small circle roughly one-third of the way between the
"equator" and the "north pole" (the "south pole" being the location of
the attachment of the satellite to a pedestal on the R-7 core stage).
This spread the aerials backwards ("southwards") and outwards in a
conical configuration. The apex angle of the cone appears to be
roughly 70 degrees, which is consistent with a 35-degree latitude of
tangential attachment. A picture of the conical shroud shows that it
faithfully followed the spread of the aerials; indeed, Sputnik 1's
aerials were probably intentionally configured this way to fit
properly under the shroud. Shroud first, satellite to fit.
The shroud was a single piece, unlike all shrouds nowadays, which are
in two (or more) pieces. A two-piece shroud may be jettisoned
laterally as soon as the launch vehicle leaves the atmosphere while it
is still firing, relieving it of dead weight. But a single-piece "nose
cone" has to remain attached to the launch vehicle until orbital
injection, at which time it is blown off and becomes a separate piece
of orbiting debris in a slightly higher orbit than the satellite it
protected. The Sputnik 1 nose cone was not catalogued by Space Track,
but early issues of "Space Log" list it as an orbited object from that
launch. Being light in weight and having a relatively large surface
area, it probably decayed within a few weeks after the launch. It
would have been the second-brightest object from the launch, being
considerably larger than the satellite itself.
No spin-up mechanism/table appears in any illustration of the Sputnik
1 launch configuration under the shroud that I've seen, and the
satellite was evidently not spun up prior to orbital insertion. It was
simply attached to a slender pedestal, where a small explosive or
compressed-gas device pushed it off the booster into orbit, shortly
after a similar mechanism blew the nose cone away. As Gerhard Holtkamp
points out, considerable thought went into the separation mechanism
and its backups. Most accounts note that the aerials were to have
"sprung out" of their launch configuration at that time, but when all
is said and done this does not seem to have been the case. What would
this new configuration have been? A somewhat wider cone, in which the
aerials were no longer tangent to the sphere? Or, did the attachment
points of the aerials mechanically move closer to the "north pole,"
leaving the aerials tangential but spread farther apart? Neither
possibility seems consistent with the primary directive to keep the
satellite as simple as possible ("Prosteyshii Sputnik," not just
"Prostoi Sputnik"). Two of the aerials were 2.4 meters long, and the
other two were 2.9 meters long, consistent with Sputnik 1's two
broadcast frequencies. There is ample room under the nose cone, of
which there is a nice but tiny diagram in the "Launch Vehicles"
booklet, for the aerials without any need for spring-loaded folding or
retracting mechanisms that might have accidentally jammed and rendered
the satellite silent. I suspect the satellite was simply pushed off
the pedestal with its aerials swept "southward" exactly as stowed
under the shroud, after which it tumbled more or less randomly in that
configuration. The aerials were long enough that a signal would be
received on the ground regardless of the satellite's orientation.
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