I cannot for the life of me remember when it was or what it was but a fair few years ago I remember positioning a telescope to observe an asteroid as it silently and perhaps slightly eerily drifted between us and the Moon. I say eerily as this asteroid had the ability to cause widespread damage had it hit but of course we knew it posed no threat. I remember at the time thinking it was mind blowing that even today, we still use mathematics with roots (pardon the pun) centuries old to calculate the position of objects in our Solar System. We get to see evidence of this again on 12th December when something rare happens!