Myth busted: Americans spent millions to make a pen that would flow in space — the Russians used a pencil

It’s a great story that reminds us complicated solutions can have very simple solutions. But the Russian pencil story is just a myth, though.

How does an eraser work?

When you rub an eraser across a pencil mark, the abrasives in the eraser gently scratch the surface fibers of the paper to loosen the graphite particles.

Could you balance a pencil on a one-atom thick tip?

It’s Saturday, so time for some fun physics. This non-trivial question is often asked in international physics contests and requires a bit of out of the box thinking.