Mars and Earth Mars is the fourth closest planet to the Sun after Earth . This distance allows it to be at suitable temperatures like Earth . It is 230 million kilometers from the Sun .
It ' s about half the size of Earth . The diameter of the Earth is 12,742 kilometers . The diameter of Mars is 6,779 kilometers .
While a day on Earth is 24 hours , a day on Mars is 24 hours and 39 minutes . This is one of the most similar points between the two planets .
The lowest temperature in the world is minus 88 degrees and the highest temperature is 58 degrees . The lowest temperature on Mars is minus 140 , and the highest temperature is 30 degrees .
Earth ' s atmosphere is 78 percent nitrogen , 21 percent oxygen , and 1 % other gases . The atmosphere of Mars is 96 % carbon dioxide and 4 % other gases .