...Why Venus is hotter than Mercury ?

Let us go over few of the facts.

Fact Set 1 :

Mercury is on an average 36 million miles away from sun.

Venus is on an average 67 million miles away from sun.

Inference 1 : Venus is almost twice as farther as Mercury from the sun.

Fact Set 2 :

The Solar Irradiance which Mercury receives is on an average 9126.6 watts per square meter.

The Solar Irradiance which Venus receives is on an average 2613.9 watts per square meter.

Inference 2 : Approximately Venus receives just one-fourth of the solar radiation which Mercury receives.

Fact Set 3 :

The average temperature of Mercury is 167 degree celsius.

The average temperature of Venus is 464 degree celsius.

Inference 3 : Approximately Venus is three times hotter than Mercury.

Inference 4 : Common sense suggests that Inference 3 is inconsistent with Inferences 1 & 2.

Facts never lie because they are facts but common sense can. This inconsistency is brought out by a gaseous substance called CO2 well known to us as Carbon-di-oxide. 96.5% of Venus' atmosphere is CO2. Does it ring a bell ? Yeah, that's right. It is because of the green house effect produced by such a huge amount of CO2 in Venus' atmosphere. This phenomenon is instrumental in making Venus the hottest planet of our solar system. Now do you get why Al Gore shouts at the top of his voice trying to warn us about the impending danger which every one of us ignore. Let us do our bit to preclude Earth from becoming a frying pan that Venus is.