Venera 16 was part of a two spacecraft mission (along with Venera 15) designed to use 8 cm band side-looking radar mappers to study the surface properties of Venus. The two spacecraft were inserted into Venus orbit a day apart with their orbital planes shifted by an angle of approximately 4 degrees relative to one another. This made it possible to reimage an area if necessary. Each spacecraft was in a nearly polar orbit with a periapsis at 62 N latitude. Together, the two spacecraft imaged the area from the north pole down to about 30 degrees N latitude over the 8 months of mapping operations. In June 1984, Venus was at superior conjunction and passed behind the Sun as seen from Earth. No transmissions were possible, so the orbit of Venera 16 was rotated back 20 degrees at this time to map the areas missed during this period.
The Venera 15 and 16 spacecraft were identical and were based on modifications to the the orbiter portions of the Venera 9 and 14 probes. Each spacecraft consisted of a 5 m long cylinder with a 6 m diameter, 1.4 m tall parabolic dish antenna for the synthetic aperture radar (SAR) at one end. A 1 meter diameter parabolic dish antenna for the radio altimeter was also located at this end. The electrical axis of the radio altimeter antenna was lined up with the axis of the cylinder. The electrical axis of the SAR deviated from the spacecraft axis by 10 degrees. During imaging, the radio altimeter would be lined up with the center of the planet (local vertical) and the SAR would be looking off to the side at 10 degrees. A bulge at the opposite end of the cylinder held fuel tanks and propulsion units. Two square solar arrays extended like wings from the sides of the cylinder. A 2.6 m radio dish antenna for communications was also attached to the side of the cylinder.
Infrared Fourier Spectrometer was installed on board Venera 15 Orbiter. The experiment was described in several papers (see, for example, Moroz et al., 1986, Oertel et al., 1987). About 2000 high quality spectra in the range 250 - 1650 cm, with spectral resolution 4.5 and 6.5 cm, were obtained. During an orbit the nearly meridional measurements were fulfilled, beginning from low latitudes to the North Pole and then back to low latitudes. As a result, we obtained practically simultaneous measurements for a wide range of latitudes at the same solar longitude (or local time). This geometry is very convenient for investigation of three-dimensional fields of temperature, solar related structures and thermal tides in the middle atmosphere of Venus (55-100 km) (text adapted from Zasova, 1999).
A preliminary dataset is available for download here (file ZIP, 4.6MB).
VENERA_15_FS_Data_[DATE] archive content:
Moroz V. I., Spankuch D., Linkin V. M., Dohler W., Matsygorin I. A. et al. Venus spacecraft infrared spectra. Applied Optics, 25, NlO (1986)
Oertel D., D. Spankuch, H. Jahn, H. Becker-Ross, W. Stadthaus, J. Nopirakowski, W. Dohler, K. Schafer, J. Guldner, R. Dubois, V.I.Moroz, V/M/ Linkin, V.V. Kerzhanovich, I. A. Matsygorin, A. N. Lipatov, A.A. Shurupov, L. V. Zasova, E.A. Ustinov. Infrared spectrometry from Venera-15 and Venera-16. Adv. Space Res., 5, N9,25 (1985)
L.V. Zasova. Author links open the author workspace.I.A. Khatountsev. Author links open the author workspace.V.I. Moroz. Author links open the author workspace.N.I. Ignatiev, Structure of the venus middle atmosphere: Venera 15 fourier spectrometry data revisited, Advances in Space Research, Volume 23, Issue 9 , (1999)