The speed of light in a vacuum is approximately 299,792,458 meters per second, which is commonly rounded to about 300,000 kilometers per second.
To calculate the time it takes for a beam of light to reach us from Mars, we need to know the distance between Earth and Mars, as well as divide that distance by the speed of light.
The distance between Earth and Mars varies depending on their positions in their respective orbits around the Sun. On average, Mars is located about 225 million kilometers away from Earth.
Using the formula: time = distance / speed, we can calculate the time it takes for light to travel from Mars to Earth.
time = (225,000,000 km) / (300,000 km/s) = 750 seconds
Converting seconds to minutes, 750 seconds is equal to 750 / 60 = 12.5 minutes.
Therefore, on average, it takes approximately 12.5 minutes for a beam of light to travel from Mars to Earth.