In addition, astronomers have found that the planet emits a glow of infra-red radiation, which has been used to make maps of the Venusian surface and to pinpoint its mineralological composition.
Unfortunately, no direct mineralogical data exist for the Venusian surface.
Now, scientists have the strongest evidence yet for ongoing volcanism (artist's concept above): relatively small "hot spots" on the venusian surface that displayed big changes in temperature over just a few days.
The pixel resolution at the Venusian surface is 0.2 1.6 km for UVI, IR1, and IR2 and 0.9 7.0 km for LIR from the periapsis altitude of 1000 8000 km.
The U.S. probe Magellan, which took off for Venus in 1989, radar-mapped the Venusian surface precisely (Saunders et al, 1992).
The detector's one pixel corresponds to 35 km resolution on the Venusian surface viewed from 1000 km altitude, and 850 km resolution from 3 Rv altitude.
The pixel resolution at the Venusian surface from the apoapsis altitude of ~360,000 km is 74 km for UVI, IR1, and IR2 and 300 km for LIR, while it is 12 km for UVI, IR1, and IR2 and 50 km for LIR from the altitude of 58,000 km where the apparent Venus disk fits into the FOV of 12°.
But beneath the clouds, the Venusian surface is anything but bland.
Radar observations in the 1970s revealed details of the Venusian surface for the first time.
Much of the Venusian surface appears to have been shaped by volcanic activity.
