Expert: Steven LJ Russo - 10/27/2006

Question
Steve:
Just wondering what the math is that gets the speed to 1,342,000? I would have been inclined to add 1,000 + 67,000 + 447,000 to get a total speed of 515,000 mph.
-------------------------------------------
The text above is a follow-up to ...

-----Question-----
I  know the earth travels about 67.000 mph around the sun to make it all the way around each year.  How fast does the earth move around the galaxy and how long does it take to complete that trip?  Thanks for considering the question.


-----Answer-----
Tom:

This is a bit tricky, as the Earths speed around the galaxy is usually not computed, since the Earth orbits the Sun, and the Sun orbits the Galaxy.  But here is a summary of all the "moving".

Earth Rotates around 1000 mph at the Equator.

Earth orbits the Sun at around 67,000 mph (66,629).

The Sun and planets orbit the Galaxy at 447,000 mph.

The combined movement of all of that is 1,342,000 mph

The Galaxy itsels rotates once in 250,000,000 years.

To get the "full" story, go to this link:

http://calgary.rasc.ca/howfast.htm#revolve

Steve


Answer
Hi Tom:

I was wondering about that too, so I checked some other sites, and they all came up with the same answer.

If you go to the origional site:

http://calgary.rasc.ca/howfast.htm#total

There is a long explanation on how this speed is "sort of" derived.

I myself, do not fully understand it :)

Steve