This morning, I was up around five o’clock to see my wife off on a business trip. My nine-year-old daughter also woke early to see her mother leave then we both headed outside to see the Super Full Moon. The Moon, now at perigee, is 14% bigger and 30% brighter that at any other time in its orbit. It’s ‘super’ because perigee happened to occur while the Moon was full – a rare event that comes around approximately every 18 years.
It was perfectly clear and a chilly 25° as my daughter and I stood outside looking at the Moon. We had a discussion about the size of the Moon and Earth, which in turn led to a discussion about the planets. My daughter surprised me by listing facts about Jupiter. “It’s the largest planet, it’s gas, has no real ground, and a lot of Earths could fit in it,” she said. But what she didn’t know was how long it would take a person to walk around Jupiter.
Putting aside the lack of a surface, killer temperatures and crushing pressure, I explained that all we needed to do was look up the circumference, around the equator, of Jupiter and how fast the average person walks. We went back inside, dug out the iPad and did some research. We found:
Jupiter’s equator is about 439,260 km (272,944 miles).
An adult walks at about 5 (km/h) (3.1 miles mph).
Then some simple math:
439,260 km / 5 km/h = 87,852 hours
87,852 hours / 24 hours = 3,660.5 days
3,660.5 days = 10.02 years
It would take ten years to walk around the circumference of Jupiter. Ten years of continuous walking. We both agreed that staring at the Moon together was a lot more fun.
