Would Venus being struck by an asteroid explain the planets temperature?

Answer 1

No. Venus temperature is due to a runaway greenhouse effect.

Venus, like all worlds in the solarsystem, has been struck by asteroids many times in their history. Yet all worlds have different characteristics and temperatures. Venus great temperture is because of its dense blancketing atmosphere which in turn is the result of its proximity to the sun along with its mass.

All the terrestrial planets probably had primordial atmospheres with similar compostition. Mercurys weak gravity probably left it stripped of its atmosphere not too long after the sun first ignited. When the sun began baking Venus, Venus greater mass was able to hold on to its gasses but it got so hot liquid water couldn´t form. So all that primoridial co2 and sulphur remained. Along with those gasses and watervapour, great greenhouse gasses all, Venus just got hotter and hotter. The water was subject to brutal ultraviolett rays from the sun which broke it down into hydrogen and oxygen. While the oxygen reacted with sulphurus oxides the hydrogen, on its own, was able to reach escape velocity and was blasted off into space. So now almost no water remains on Venus.
Earth, however, was slightly cooler. Here water was able to condensate and immediately co2 began dissolving. It reacted with metalhydroxides, also dissolved in the water, to form carbonates. Alot of earth primordial co2 is still locked up in carbonates. If it were all released at once earths atmosphere would increase in density about 70 times... (Venus atmosphere is about 90 times as dense as earths.)

Answer 2

Its possible, any interference in space causes disruptions in our atmosphere so that could include our weather system..

Answer 3

No .. it's the density and composition of the atmosphere.