Answer:
in the 1700s, they helped us determine our distance to the Sun and gave us the first clue that Venus might have an atmosphere.
Step-by-step explanation:
the atmosphere started to get thicker , making Venus hotter and hotter, until the carbon itself from the rocks evaporated (or sublimated) into the atmosphere, mixing with oxygen to form carbon dioxide. The atmosphere got thicker, and the planet got hotter and hotter, until it turned into the world we see today. We call this a runaway greenhouse effect. hope it helps