Wednesday, December 31, 2008

Happy New Orbit!

As we approach to within 5 million kilometers of the arbitrary point at which we've declared one orbit of the Earth around the Sun to end and the new one to begin, I wanted to wish everyone a happy new orbit!

This year, the Sun has traveled about 0.00000144 degrees around the center of our galaxy, the Milky Way. This means we on Earth have followed our sun 6,591,881,796 kilometers through space relative to the center of our galaxy. If that starts to seem like a long way, remember that's only about 0.0007 light years.

The Earth itself has traveled about 939,955,097 km in its orbit around the Sun.

And we here on the surface of the Earth, living at about 38 degrees north of the equator, will have spun around 365.242 times since the start of the present orbit. This means that we've travelled about 11,534,832 km relative to the center of the Earth.

So, to see how much you've gotten around this last orbit, get the following:
About how far you walk in a day, times 366 and the mileage off your car's odometer, then add it to the distances above (given in miles below, since my car's odometer is calibrated in miles.)

Solar orbital travel about galactic center: 4,096,030,281 mi.
Earth orbital travel around Sun: 587,471,955.8 mi.
Earth surface travel about Earth center: 7,209,279.2 mi.

Cumulative distances (all added up) are:
4,690,711,519 miles, or,
7,505,138,430 km.
plus whatever miles you travelled personally on the surface of the Earth. Figure about 0.00078 light years. As they say, it's not the years, it's the mileage.

In the past orbit we've improved our view of the Andromeda galaxy by coming about 8,678,149,920 km closer to it. That's an improvement of about .0009 light years out of about 3 million. Our views of the Magellanic clouds has gotten worse, however, with them getting about 8.5 billion km farther away for the Large Magellanic Cloud and about 5.3 billion km farther for the Small Magellanic Cloud. The compensation is that the Triangulum galaxy, M33, is now about 6 billion km closer. So views of objects in the Local Group of galaxies gets better and better for us here in the northern hemisphere.

Happy New Orbit, everyone!