Calculating Light's Journey (in the wild)

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Light travels at about 300,000 kilometers per second. To figure out how long it takes light from the sun to reach a planet, including Earth, I can use this formula:

𝑡=𝑑/𝑐

where 𝑡 = is the time it takes in seconds, 𝑑 = is the distance from the Sun to the planet in kilometers, 𝑐 = is the speed of light (300,000 km/s).

Since Earth is about 149.6 million kilometers from the Sun, it takes light:

𝑡 = 149,600,000,000,000/300,000 = 500 seconds (about 8 minutes and 20 seconds)

Using the same formula, I can figure out the time it takes light to reach different planets:

Mercury: 3 minutes 13 seconds
Venus: 6 minutes
Mars: 12 minutes 40 seconds
Saturn: 79 minutes 28 seconds
Jupiter: 43 minutes 16 seconds
Uranus: 2 hours 40 minutes
Neptune: 4 hours 10 minutes

And finally for Neptune it is a mind-blowing 4 hours 10 minutes!!!

By using this formula and the distance, I can calculate how long light takes to reach any planet from the Sun.

— Haridarshan Bhatt (S2)