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Because 6 trillion miles is such a huge number, we really need to break it down to understand just how far it is. So let's start by looking at a light second. Since light moves at 186,000 miles per second, a lightsecond is 186,000 miles. The moon is about 1.3 lightseconds away. Since the circumference of the earth is about 25,000 miles, light could travel all the way around the earth 7 and a half times in one second.
A millisecond is a thouandth of a second. So a lightmillisecond is 186 miles. This is a distance we all can find easier to understand. In a thousandth of a second, light travels 186 miles.
A microsecond is a millionth of a second. So a light microsecond is about 0.186 miles, or roughly 1,000 feet.
A nanosecond is a billionth of a second. So a light nanosecond is about one foot, or 30 centimeters. Every nanosecond, light travels one foot. This is actually important in the computer industry, because lots of things inside modern computers can happen in a nanosecond or less. The maximum distance that light can travel in a nanosecond controls how big and fast computers can be.
What if we go the other direction? There is the lightminute. It is 60 lightseconds, or about 11 million miles. And a lighthour is 60 lightminutes, or about 670 million miles. Our solar system is about 8 lighthours across. In other words, it takes light roughly four hours to get from the sun to Neptune.
You can really impress your friends with this information. The next time someone says, "Hey, I just rode my bike 10 miles!", you can say, "that's about 53 lightmicroseconds. It would take light 53 microseconds to go 10 miles."
This table is a quick summary:
|lightnanosecond||1 foot||30 cm|
|lightmicrosecond||1,000 foot||300 m|
|lightmillisecond||186 miles||300 km|
|lightsecond||186,000 miles||300,000 km|
|lightminute||11 million miles||18 million km|
|lighthour||670 million miles||1 billion km|
|lightyear||6 trillion miles||10 trillion km|