Dealing with very large and very small numbers

[Cliff Hanley]

Are the following correct (all numbers are approximations);

d from the Earth to the Sun is 90 million miles = 9 x 10^ 7 miles = 144 million km = 1.44 x 10 ^ 8 km ?

d from the Earth to the Moon is 240 thousand miles = 2.4 x 10^ 5 miles = 400 thousand km = 4 x 10 ^ 5 km?

m of the Earth = 6 x 10 ^ 24 kg = 6 septillion kg = 6 trillion trillion kg ?

m of electron = 9 x 10 ^ -31 kg = 90 nonillionths of a kg = 9 x 10 ^ -28 g = 90 octillionths of a g ?

 

[RUber]

I think your last line is wrong.
A nonillionth should be 10^-30. So 10^-31 is 1 tenth of a nonillionth.
Same thing with octillionths, 9x 10^-28 = .9 x 10^-27, or .9 octillionths, which would be 900 nonillionths.