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Venera 2
| title |
Venera 2 |
| date |
11.12.1965 |
| description |
Although the 3MV-3 and 3MV-4 type spacecraft were originally intended for Mars exploration, the Soviets re-equipped three of the series, left over from the 1964 Mars launch windows, for Venus exploration in 1965. This particular vehicle was scheduled to fly past the sunlit side of Venus at no more than a 40,000-kilometer range and take photographs. During the outbound flight, communications with the spacecraft were poor. Immediately before closest approach in late February 1966, ground control commanded to switch on all the onboard scientific instrumentation. o The closest approach to the planet was at 02:52 UT on 27 February 1966 at about a 24,000-kilometer range. After its flyby, when the spacecraft was supposed to relay back the collected information, ground control was unable to regain contact. Controllers finally gave up all attempts at communication on 4 March. Venera 2 eventually entered heliocentric orbit. Later investigation indicated that improper functioning of 40 thermal radiator elements caused a sharp increase in gas temperatures in the spacecraft. As a result, elements of the receiving and decoding units failed, the solar panels overheated, and contact was lost. Ironically, the scientific instruments may have collected valuable data, but none of it was ever transmitted back to Earth."Editor's Note: This mission profile was originally published in *Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000*, by Asif A. Siddiqi, NASA Monographs in Aerospace History No. 24" |
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Venera 11
| title |
Venera 11 |
| date |
09.09.1978 |
| description |
Venera 11 was one of two identical probes (the other being Venera 12) that followed up on the highly successful Soviet missions to Venus in 1975. Veneras 11 and 12 differed from their predecessors principally in the fact each carried a flyby bus/lander combination instead of the previous orbiter/lander combination. Engineers reverted to the flyby combination partly because of the weight limitations of the 1978 launch window, but also because flyby probes afforded better transmission time for landers. Several of the scientific instruments were also modified and new ones added. Venera 11 arrived at Venus after two course corrections on 16 September and 17 December 1978. On 23 December 1978, the lander separated from the flyby probe and entered the Venusian atmosphere two days later. The lander probe safely landed on Venus at 03:24 UT on 15 December 1978 and then relayed 95 minutes of data from the surface. Landing coordinates were 14° south latitude and 299° longitude. The point of cutoff was determined by the range of visibility of the flyby probe. A soil-drilling instrument collected soil for chemical and physical analysis, but soil analysis was unsuccessful because the soil was not properly deposited to an examination container for analysis (probably due to leaking air that disturbed the soil). The lander also failed to take color panoramas of the Venusian surface due to a failure of the lens covers of the camera system to open. While extensive atmospheric data was later released, the Soviets have published relatively little data from surface measurements. The flyby probe entered heliocentric orbit after flying past the planet at a range of 35,000 kilometers. |
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Venera 14 Lander
| title |
Venera 14 Lander |
| date |
11.04.1981 |
| description |
Venera 14 was identical to its twin, Venera 13. The spacecraft carried out three midcourse corrections on the way to Venus: on 14 November 1981, 23 November 1981, and 25 February 1982. Russian sources indicate that one of the corrections was incorrect (probably the first) and could have jeopardized the mission. The lander probe separated from its flyby parent on 3 March 1982 before the entry cycle began. The probe's main parachute opened at an altitude of 62 to 63 kilometers, thus activating the atmospheric instruments. The parachute was released at an altitude of 47 kilometers, and the 760-kilogram lander fell to the surface using only the atmosphere as a retarding medium. The probe made safe contact with the Venusian surface at 07:00:10 UT on 3 March 1982 and continued with 57 minutes of transmissions. Landing coordinates were 13.25° south latitude and 310° longitude, about 1,000 kilometers from the Venera 13 landing site. As with its twin, Venera 14 returned color photographs of its surroundings and examined a soil sample (about 1 cubic centimeter taken from a 30-millimeter-deep sample). Soil was deposited in a chamber sealed off from the outside environment and was then progressively transferred through a series of chambers by blowing air until the sample was deposited in its final chamber with a temperature of only 30°C. Here it was examined by the x-ray fluorescence spectrometer. Temperature and pressure outside were considerably higher than at the Venera 13 site: 470°C and 93.5 atmospheres, respectively. The flyby probe, meanwhile, passed Venus at a range of 36,000 kilometers and entered heliocentric orbit, continuing to provide data on solar x-ray flares. It performed one trajectory change on 14 November 1982. |
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Venera 15
| title |
Venera 15 |
| date |
06.02.1983 |
| description |
Venera 15 and Venera 16 were a pair of dedicated radar mappers designed to extend the studies begun by the American Pioneer Venus Orbiter in constructing a detailed map of the surface down to a resolution of about 1 to 2 kilometers. For these missions, Soviet engineers lengthened the central bus of the earlier Veneras (by 1 meter), installed much larger solar batteries, and attached a large side-looking radar antenna in place of the descent lander module on the earlier spacecraft. Venera 15 carried out two midcourse corrections (on 10 June 1983 and 1 October 1983) before successfully entering orbit around Venus at 03:05 UT on 10 October. Initial orbital parameters were 1,000 x 65,000 kilometers at 87° inclination -- that is, a near-polar orbit. The spacecraft's mapping operations began six days after entering orbit over the north pole. Because of the nature of the spacecraft's orbit, the two orbiters mapped only the area from 30° north latitude to the pole -- about 115 million square kilometers -- before the mission was completed on 10 July 1984. |
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Venera 9
| title |
Venera 9 |
| date |
06.08.1975 |
| description |
Venera 9 was the first of a new generation of Soviet space probes ('4V') designed to explore Venus. Launched by the more powerful Proton launch booster, the new spacecraft were nearly five times heavier than their predecessors. Each spacecraft comprised both an orbiter and a lander. The 2,300-kilogram orbiters (at Venus orbit insertion) were designed to spend their missions photographing the planet in ultraviolet light and conducting other scientific investigations. The landers, of a completely new design, employed aerodynamic braking during Venusian atmospheric entry and contained a panoramic photometer to take images of the surface. Without any apparent problems and with two trajectory corrections (on 16 June and 15 October), Venera 9's lander separated from its parent on 20 October 1975, and two days later, it hit Venus's turbulent atmosphere at a speed of 10.7 kilometers per hour. After using a series of parachutes, the lander set down on the planet's day side at 05:13 UT on 22 October. Landing coordinates were 32° north latitude and 291° longitude at the base of a hill near Beta Regio. During its 53 minutes of transmissions from the surface, Venera 9 took and transmitted the very first picture of the Venusian surface from a height of 90 centimeters. These were, in fact, the very first photos received of the surface of another planet. The lander was supposed to transmit a full 360° panorama, but because one of the two covers on the camera failed to release, only a 180° panorama was received. Illumination was akin to that of a cloudy day on Earth. The image clearly showed flat rocks strewn around the lander. The Venera 9 orbiter meanwhile entered a 1,500 x 111,700-kilometer orbit around the planet at 34°10' inclination and acted as a communications relay for the lander. It became the first spacecraft to go into orbit around Venus. The Soviets announced on 22 March 1976 that the orbiter's primary mission, which included using French-made ultraviolet cameras to obtain photographs in 1,200- kilometer swaths, had been fulfilled. |
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The Surface of Venus from th
…
| title |
The Surface of Venus from the Venera 10 Lander |
| date |
10.25.1975 |
| description |
Venera 10 Lander image of the surface of Venus at about 16 N, 291 E. The Lander touched down at 5:17 UT on 25 October 1975 and returned this image during the 65 minutes of operation on the surface. The sun was near zenith during this time, the lighting was about what would be seen on Earth on an overcast summer day. The objects at the bottom of the image are parts of the spacecraft. The image shows flat slabs of rock, partly covered by fine-grained material, not unlike a volcanic area on Earth. The large slab in the foreground extends over 2 meters across. Automatic gain control and logarithmic quantization were used to handle the unknown dynamic range of illumination. The raw image was converted to optical density according to Russian calibration data, then to linear radiance for image processing. It was interpolated with windowed sinc filter to avoid post-aliasing (a "pixilated" appearance), and the modulation transfer function ("aperture") of the camera was corrected with a 1 + 0.2*frequency**2 emphasis. This was then written out as 8-bit gamma-corrected values, using the sRGB standard gamma of 2.2. The bottom image is a digitally in-painted version, using Bertalmio's isophote-flow algorithm. (Venera 10 Lander, processed surface image) (Image posted with permission, copyright 2003 Don P. Mitchell. All rights reserved.) *Image Credit*: NASA |
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Venera Test
| title |
Venera Test |
| date |
06.08.1975 |
| description |
A rare picture of Russian engineers testing a Venera Venus lander. This type of lander was used in the Venera 9 and 10 missions to the surface of Venus. *Image Credit*: NASA National Space Science Data Center |
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Venera 10
| title |
Venera 10 |
| date |
06.14.1975 |
| description |
Venera 10, like its sister craft Venera 9, fully accomplished its mission to soft-land on Venus and return data from the surface. The spacecraft followed an identical mission to that of its twin, arriving only a few days later after two trajectory corrections on 21 June and 18 October 1975. The 660-kilogram lander separated from its parent on 23 October and entered the atmosphere two days later at 01:02 UT. During reentry, the lander survived gravity acceleration as high as 168 g and temperatures as high 12,000°C. It performed its complex landing procedures without fault and landed without incident at 02:17 UT approximately 2,200 kilometers from the Venera 9 landing site. Landing coordinates were 16° north latitude and 291° longitude. Venera 10 transmitted for a record 65 minutes from the surface, although it was designed to last only 30 minutes. A photo of the Venera 10 landing site showed a smoother surface than that of its twin. Like Venera 9, the Venera 10 lander was supposed to take a 360° panorama but covered only 180° of the surroundings because of a stuck lens cover. Meanwhile, the Venera 10 orbiter entered a 1,400 x 114,000-kilometer orbit around Venus inclined at 29°30'. Soviet officials later revealed that the termination of data reception from both Veneras 9 and 10 was not caused by the adverse surface conditions but by the flying out of view of the orbiter relays for both spacecraft. Gamma-ray spectrometer and radiation densitometer data indicated that the surface layer was akin to basalt rather than granite as hinted by the information from Venera 8. |
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Venera 3
| title |
Venera 3 |
| date |
11.06.1965 |
| description |
This was the second of three 3MV spacecraft the Soviets attempted to launch toward Venus in late 1965. Venera 3 successfully left Earth orbit and released a small 0.9- meter-diameter, 337-kilogram (some sources say 310-kilogram) landing capsule to explore the Venusian atmosphere and transmit data on pressure, temperature, and composition of the Venusian atmosphere back to Earth during the descent by parachute. During the outbound trajectory, ground controllers successfully performed a midcourse correction on 26 December 1965 and completed 93 communications sessions. However, contact was lost on 16 February 1966, shortly before the Venusian encounter, although the spacecraft automatically released its sterilized lander probe, which landed inertly on the Venusian surface at 06:56 UT on 1 March 1966. It was the first time a humanmade object had made physical contact with another planetary body besides the Moon. Later investigation confirmed that Venera 3 suffered many of the same failures as Venera 2, such as overheating of internal components and the solar panels. |
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