It can be difficult to grasp just how enormous the solar system is. At the heart of that system is the sun, the star around which all the planets orbit. Even though those planets seem impossibly far away, scientists are able to calculate where they will be in their rotations at any given moment, and how many light years they are traveling away from Earth.
Calculating Light Years
Because the galaxy is so huge, astronomers had to come up with a unit of measurement able to convey such incredible distance. The result was the light year, which covers the distance that light travels in one year. That distance is nearly 6 trillion miles, but a light year conveys time more than it does actual distance. For instance, if you are running late to meet a friend, you might say, “I’m 20 minutes away,” instead of “I’m 3.2 miles away.”
This makes it easier to understand just how far away the planets, stars, asteroids and comets are from Earth or from the sun. Instead of having to comprehend what it means when a planet is trillions and trillions of miles away, thinking in light years can help you visualize how long it takes for light to travel from one spot to the other. For instance, if you see a photo of a galaxy that is 90 million light years away, you’re actually getting a glimpse of what that galaxy looked like 90 million years ago.
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Planet Distances From the Sun
Planets are far closer to Earth than distant galaxies, so seeing a planet through a telescope or in a photo is not such a distant view into the past. In fact, it’s common to measure planet distances from the sun in light minutes or light hours as opposed to light years, since those numbers are smaller and easier to comprehend. For instance, Mercury is the closest planet to the sun. On average, it is about 36 million miles away. In light years, that number would be 0.000006123880620837039 light years away. It’s much easier to say that it is about 3.3 light minutes away, meaning it would take about 3.3 minutes for light to travel between Mercury and the sun.
The other average distances from the sun to the planets are as follows:
Venus: 0.000011397222266557821 light years, or about 6 light minutes away from the sun.
Earth: 0.00001582002493716235 light years, or about 8.3 light minutes away from the sun.
Mars: 0.000024155306893301653 light years, or about 12.7 light minutes away from the sun.
Jupiter: 0.00008233217279125351 light years, or about 43 light minutes away from the sun.
Saturn: 0.0001505453985955772 light years, or about 1.3 light hours away from the sun.
Uranus: 0.0003027918751413869 light years, or about 2.7 light hours away from the sun.
Neptune: 0.00047460074811487044 light years, or about 4.2 light hours away from the sun.