7/23/2023 0 Comments Mars imagesThe raw data is almost unviewable, so I have done some computer processing for horizontal sync, dark current and charge-transfer effects, as discussed in Televizionnye Issledovaniia Fobosa. It was built by a team from Buylgaria, East Germany and the Soviet Union, and extensive image processing was performed at IKI and the Keldysh Institute.Ĭhannel 1 was wide angle with a blue-green filter (400-600 nm), channel 2 was narrow angle with clear filter (400-1100 nm), and channel 3 was wide angle with near-infrared filter (800-1100 nm). The elongated horizontal smudge seen in some images is the shadow of Phobos, traveling in nearly the same orbit as the spacecraft:įobos-2 carried the video-spectrometric complex (VSK), three CCD cameras and a spectrometer. That operated simultaneously in red/near-infrared light (600 - 950 nm) and far thermal infrared (8.5 - 12 μ), using a cryogenically cooled detector. The last successful Soviet space probe, Fobos-2 arrived in Martian orbit on January 30, 1989. The camera scanned a 30° wide swath, returning 256 or possibly 512 pixels per scanline (including a squarewave calibration pattern during the retrace interval, not shown here). Scanned the planet while the spacecraft moved in its orbit and remained in a 3-axis stabilized orientation. Images transmitted only in 220-line resolution are presented as icons with no image link. Unless otherwise indicated, the Vega pictures are shot through its red filter. Images were transmitted in a rapid 220-line mode, and then selected pictures were retransmitted at 880 or 1760 line resolution. The "Vega" camera used a wide area 52mm lens with color filters, the "Zulfar" camera used a telescopic 350mm lens and long-pass orange filter. Nearly synchronized with the rotation of the planet, its twoĬould be commanded to take 12 pictures during each close approach. Mars-5 entered an elliptic Martian orbit on February 12, 1974. Red and orange filter images have been published, but apparently no infrared panoramas were received from Mars-4 or Mars-5. These were very similar to cameras later flown on Venera-9 and 10 orbiters, but one of the Mars versions had a photomultiplier tube sensitive to infrared. Swept out panoramas of Mars as the spacecraft passed by. Image data was returned digitally by pulse position modulation. It also returned 2 panoramas from the optical-mechanical cameras. During its flyby on February 10 1974, it returned 12 photographs from the 52mm "Vega"Īll through the red filter. The first in an armada of four spacecrafts launched in 1973, Mars-4 failed to enter orbit. It is not likely a view of the Martian horizon as some people have suggested: After extensive analysis, Soviet scientists report that it contains no information. It should probably be rotated 90° since the Mars-3 cameras were of the sameĪs Luna-9, scanning vertically. The image below right is reported to be a view of that signal. The red-filter image, published elsewhere, is evidently one of the channels used in the composite:Ī descent vehicle released by Mars-3 became the first probe to land on Mars, but it only operated for about 20 seconds, returning some data and 79 scan lines of video. The color image below is a composite from the 52 mm camera, using its program of cycling red, green and blue glass filters. Only after important science data was gathered, a small number of images at low resolution were transmitted The decimeter transmitter suffered from intermittant failures and was used very cautiously. Images were returned by pulse-code modulation over the decimeter-band telemetry channel, after the centimeter-band pulse-position modulation system failed. At least four photographic surveys have been reported (Dec 12, 14, Feb 28, Mar 12). Mars-2 did not return much data because of problems with its telemetry systems.Ĭontrary to some reports, the phototelevision cameras on Mars-3 were functional after the dust storm subsided, in December. The photo below left shows the atmospheric limb during the dust storm, from a distance of 150,000 km (the orbit of Mars-3 was highly elongated). However, Mars was experiencing a severe planet-wide dust storm when the Soviet probes (and the American Mariner-9) arrived. The original plan was to spend the first 40 days performing photographic surveys Selivanov and his team at the Institute of Space Device Engineering. (later used on Mars-4 and 5), carrying enough film for 480 photos per camera. They carried the 52mm "Vega" and 350mm "Zulfar" The first Soviet orbiters, Mars-2 and Mars-3 arrived on November 27 and December 2, 1971. After some success in 19, the Russians focused primarily on the study of Venus. Soviet Mars probes in the 1960s were far ahead of their time but suffered a series of unlucky failures.
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