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Luna 3 - the first view of the moon's far side

• The flight starts - everything looks good on 4 October

• Erratic signals on 5 October - Korolev dashes to the control centre

• Korolev takes command - reliable contact re-established on 6 October

• Film from American "spy balloons"!

• The images are transmitted - but when?

• References and Notes

One of the origins of Luna-3 was the work by Boris Raushenbakh on attitude control started in 1955 in the NII-1 rocket research institute of the Ministry of Aviation. This work was co-ordinated with Korolev's design bureau and had as its goal stabilised photo-reconnaissance satellites. Raushenbakh's group was contracted by the lunar project section Korolev's design bureau OKB-1 to design the attitude control for the E-2 variant of lunar exploration craft intended to image the Moon's hidden side. The manager of the lunar probe project at OKB-1 was Gleb Maksimov. An excellent account of these early Soviet lunar missions can be found in (4) and (14). A cutaway sketch of the space probe with a Soviet-era translation of Russian captions added is shown below.

The radio system was designed by deputy chief designer of the NII-885 (Scientific Research Institute of Radio Instrument Building, established 1938), Yevgeniy Boguslavskiy at NII-885 and it provided trajectory measurements, telemetry and command and command verification functions. Boguslavskiy and Boris Chertok (1) (deputy chief designer at Korolev's OKB-1) preferred pulsed systems for telemetry and ranging ever since the 1940's when Boguslavskiy had criticized the German use of carrier based radio systems in their missiles. However for E-2A Boguslavskiy surprised everyone by designing a continuous carrier system. The explanation was that tried and true methods were quicker and safer to develop under a rushed schedule. Boguslavskiy later explained that the lack of contrast in the pictures from Luna-3 was caused by lack of onboard transmitter power. The low contrast of the Luna-3 images is partly due to the fact that the Moon was illuminated from above. There isn't much contrast in a full moon. The electronics of Luna-3 was transistorized, an innovation that was regarded as risky.

Boguslavskiy and the NII-885 was also responsible for setting up the ground station at Kochka mountain near Simeiz in the Crimea in cooperation with the military unit 32103. The station was placed on the southern slope of a mountain facing the Black Sea. It was formally a part of NII-4 under general Sokolev (1). The location probably had something to do with the fact that the Crimean Astrophysical Observatory and the Physical Institute of the USSR Academy of Sciences was, and is, located at Simeiz. The ground station and control center had been in operation since 23 September 1958, i.e the same day that the very first Soviet attempt to reach the moon was made (14).

The flight starts - everything looks good on 4 October

The E-2A probe was sent to Tyuratam in August 1959 even though it was not ready for flight. Final testing would be performed at the launch site. Chertok traveled to the launch site on 17 September and the probe was declared ready for launch on 25 September (1). In the small hours of 4 October 1959, a mere two years after the launch of Sputnik, the Soviet Union launched its most impressive space spectacular ever - Luna 3 - the first space vehicle to catch a view of the moon's hidden far side. The E-2A probe weighing 278.5 kg lifted off at 0043:39 UT on an 8K72 rocket from Baikonur. The space probe was placed in an earth orbit with perigee at 48280 km, apogee at 468300 km and an inclination to the equator of 55 degrees (5). During its flight, that lasted until 29 April 1960 when it decayed in the Earth's atmosphere, Luna 3 was to bring credit to its creators and put the British Jodrell Bank radio telescope into the media focus.

Korolev wanted that the TASS communiqué of the launch of the probe mentioned the objective of photographing the Moon's far side, but less courageous minds prevailed (1). Soviet media announced that Luna 3 transmitted signals on 39.986 MHz that consisted of pulses 0.2-0.8 seconds long sent at a repetition rate of 1 +/- 0.15 Hz. The transmitter on 183.6 MHz was also used for tracking (trajectory determination). Information from the probe was sent at intervals of 2-4 hours/day. On 4 October 1959 the transmitters were to be switched on at 1300 MT (1000 UT) to operate for two hours (until 1200 UT) at a point 108000 km over 80 degrees east and 5 degrees south. At this time everything appeared to be in good shape (1).

For Luna 3, the Soviet Union again provided Jodrell Bank with pointing information for its telescope during the Luna 3 flight. Such data were sent on 4,7,8,9 October 1959 and on several more days in October 1959. Therefore, Jodrell Bank successfully picked up Luna 3 less than ten hours after launch: Signals on 183.600 MHz were received at 1206-1220.25 UT on 4 October 1959 (this agrees reasonably well with the schedule announced by the Russians at launch - see above). Jodrell Bank kept their colleagues at NASA up to date with its tracking activities on a daily basis. Pointing information from the Russians were obviously also relayed to NASA (8). In general, observations were sent both to the USA and the USSR. All data from the USSR were forwarded to the U.S., but not vice versa. Comprehensive reports including tape recordings were sent to Moscow after the flight was over. The reports to NASA were sent to the telegram address SPACE CONN NASA WASH DC (for the attention of an individual called Bryant).

Erratic signals on 5 October - Korolev dashes to the control centre

Boguslavskiy offered the opinion that the problems the following day was caused by an unfortunate "dip" in the antenna diagram of the probe. Korolev interviewed the operators of the control center and found that the work of various operators was inadequately co-ordinated and that military officers formed a second tier of direction for the operators. Korolev now ordered that only Boguslavskiy would direct operations during communication sessions with the probe. At 1600 MT (1300 UT) telemetry was received and to everybody's surprise everything worked well onboard the spacecraft. During this communications session the probe made its closest approach to the Moon at 1416 UT on 6 October 1959 when Luna 3 passed over the lunar south pole at a distance 7884 km from the moon's centre.

Jodrell Bank observed Luna-3 again (11): "Signals received Oct. 6 183.6 Mc/s only. 1342-1405.40 UT:15 sec on 15 sec off (probably the off period represents a frequency shift). 1405.40-1409.30 UT: No signals in band. 1409.30-1510 UT: usual bleeps. 1510-1538 UT: Modulation as in first period." There were two signals in the band with about 5 kHz separation (11). Was the silence at 1405.40-1409.30 UT caused by the probe's passing behind the edge of the moon?

Chertok (1) recalls that after the communications session all went out with Boguslavskiy to smoke. An ice-cold wind was blowing while the men watched the coastal resort area in the light of the setting sun. Boguslavskiy pointed out a naval vessel at sea that was there to check for radio interference. Korolev demanded that a plan was drawn up for operations the following morning when the pictures of the Moon were to be taken. At that point the designer of the Yenisey imaging system, Brazlawez, worried that the available film in the image recording system was not sufficient and pointed out that the idea was that Korolev's flight from Moscow should have brought extra film. Korolev was furious, but arranged via Rudnev that another Tu-104 would take the film from Moscow to Simferopol where it would be fetched by helicopter.

I took this picture in May 2008 at the Musuem honouring the chairman of the Academy

of Sciences during the heroic space era, Mstislav Keldysh. It shows the team behind

Luna-3 gathered at the ground station at Simeiz in the Crimea on 8-9 October

1959. Don P Mitchell helped me straighten the picture and removing the reflections

in the cover glass. From left to right: N.S. Lidorenko, I.I. Pikovskiy, M.V.Keldysh,

A.V.Belousov, S.P. Korolev, Y.Y. Boguslavskiy (deputy chief designer, NII-885),

M.S. Ryazanski (chief designer, NII-885)

The images are transmitted - but when?

The film was developed, fixed and dried on board. Thereafter it could be scanned with a light beam with up to 1000 lines per image for transmission to Earth. Radio observations at Jodrell Bank on 7 October 1959 were described as (12): "Signals on 183.6 Mc/s 1400-1459 UT. 39.986 MHz for about 3 minutes before 1505 UT. The probe appeared to be 1-1.5 degrees above the elevation given by the Russians. CW at one of several frequencies near 183.6 MHz between 1400 and 1412. Bleeps from 1412 to end. Bleeps on 39.986 MHz. The two frequencies were not on together." This description of the signal does not seem to indicate that a picture transmission similar to facsimile was being made.

"The very weak signals returning to Earth from Lunik III could not be picked up by standard Elint collection facilities and equipment. Through the co-operation of the University of Manchester in England, therefore, use of the 250-foot radiotelescope at Jodrell Bank was obtained. The Soviets announced that pictures of the far side of the moon were taken between 0330 and 0410 UT on 7 October 1959. Jodrell Bank succeeded in getting a signal on the announced frequency of 183.6 megacycles between 1410 and 1445 UT that date. A ten -hour lag behind the actual picture-taking is not excessive: the film had to be developed, and then the electronic scanning and transmission had to wait until rotation of the Earth brought the Soviet deep-space station in the Crimea into position to pick up the signal. The graduate students working for Sir Bernard Lovell at Jodrell Bank, however, in recording their intercept, narrowed the receiver bandwidth so far, in order to increase signal-to-noise ratio, that they "clipped off" much of the video information. Confirmation that the Lunik III pictures released by the Soviets were valid thus rested on a single poorly recorded intercept from which it could be judged only that the picture was more likely of a test pattern than of the moon. The signal bandwidth, however, was compatible with the parameters announced by the Soviets, and on the basis of technical extrapolation it could be concluded that the Soviet lunar pictures were authentic."

This assessment is interesting. In my opinion the picture transmission took place on 7 October, but also perhaps some 10 days later after which date the rumors in Moscow about the reception became rampant (9). In (7) it is mentioned that two transmission rates were available: "a slower transmission at great distances, and a faster transmission on approaching the Earth" and that image transmissions were made from distance of 467000 km (near apogee of the post-flyby trajectory). Perhaps the pictures sent at apogee were not good enough for publication but those received later were. We know that the pictures were transmitted in some kind of facsimile format, frequency-modulated on the carrier. So it seems that there were pictures sent on 7 October, but exactly when did the second transmission - if any - take place?

In (17) there are graphs showing the signal strength on 183.6 MHz during the flight of Luna-3. Clearly, signal levels on 5 October were very low (see figure below). However, the interesting thing about this reference is that transmission times after the images were taken near the Moon can be deduced (see table above left). The signal strength on the 16 and 17 October was very much better than nearer the Moon. Probably, this is when the good pictures were received.

Imaging system

This is what Don P. Mitchell writes at his web site: "On October 7, 1959, Luna-3 returned the first images of the hidden side of the Moon. Using a phototelevision camera, pairs of images were simultaneously exposed through 200mm and 500mm lenses. The Luna-3 camera was developed by P.F. Bratslavets and I.A. Rosselevich at the Leningrad Scientific Research Institute of Television. The images were processed and analyzed by Iu.N. Lipskii and his team at the Sternberg Astronomical Institute.

The camera held 40 frames of film, and 12 images were received via frequency-modulated analog video (some reports claim 17 images were received). The full moon appears to have very little detailed texture, because the lunar mountains and terrain casts no shadows when lit from overhead. The fine stiple seen in some images may be the video subcarrier. .."

Six of the Luna-3 frames have been published and can be found at Don P. Mitchell's excellent site.

http://www.svengrahn.pp.se/trackind/luna3/Luna3story.html

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