Final answer:
The brightness of the Sun on Mars compared with its brightness on Earth is about 1.96 times dimmer.
Step-by-step explanation:
The brightness of the Sun on Mars compared with its brightness on Earth can be determined using the inverse square law of brightness. According to the law, the brightness of an object decreases inversely with the square of the distance. The average distance of Mars from the Sun is 1.4 AU, which is about 210 million kilometers. Comparing this distance to the average distance of Earth from the Sun, which is 1 AU or about 150 million kilometers, we can find the ratio of the brightness.
Since the distance to Mars is larger than the distance to Earth, the brightness of the Sun on Mars would be lower than its brightness on Earth. Using the inverse square law, we can calculate the ratio of brightness by taking the square of the distance ratio. In this case, the distance ratio is (210 million km / 150 million km) = 1.4. Taking the square of 1.4 gives us approximately 1.96.
Therefore, the Sun is about 1.96 times dimmer on Mars compared with its brightness on Earth.