Refocusing a camera lens onto radioactive material.
Going farther into physics results in some interesting numbers.
The mass of the sun is 1.48 kilometers.
The mass of an electron is 0.510 mega-electronvolts.
And of course the greatest equation relating the speed of light and Newton’s gravitational constant:
c = G = 1
The great thing about the above equation is that everything can be measured in terms length and units no longer pose a problem, just add them in until the equation balances.
And compared to the sun the earth has a mass of 0.443 centimeters.
