On the golden record that accompanies the Voyager spacecraft, there is a map showing the location of Earth. It’s not a road map that you might pull out when navigating a city, but a 3D map showing the location of a star, the Sun, in a populous galaxy. But just how would this map work? And more importantly, what are the map markers? If you notice the lines at the bottom left of the golden record image, they all intersect at a common center point. This is the Sun, and the lines extend out showing relative distances to the nearest...
Categorizing objects in the universe can be difficult. The fiasco with Pluto over the last decade is more than proof of that. We generally look to location and then to size as the two main methods for classifying the stuff that permeates the cosmos. Galaxies contain stars, which host orbiting planets, which host orbiting moons; While asteroids fly in between planets and icy comets are wander through the outskirts of star systems. But what about the in-between objects? Often we find strange things in strange places. There are moons in our solar system that are larger than planets. What would...
