Answer to Question 1
They were the first spacecraft to soft land on the planet and send images of the surface back to Earth.
Answer to Question 2
Uranus passed in front of a star, and the star's light fluctuated before and after the occultation. These rapid changes were mapped by photoelectric photometry to map the rings. Later observations found them brighter in the infrared, for as the dark material absorbs sunlight, the absorbed energy heats up the rings particles to the point that in the infrared, they are hotter than the planet's surface clouds.
There are several laws of thermodynamics critical to understanding physical processes. Two of those
A simulated-color map of the surface of Venus as measured by synthetic aperture radar on the Magella
Russian federation stamp illustrating Yuri Gagarin, first human in space
Anatomically modern humans left archaeological clues, including evidence of burials, which indicate
Henri Matisse, Venus.
In 1964 a team of Russian scientists smashed a neon nucleus into a plutonium tar