Ok we need to talk about this. I just now found out about these things and they are literally the coolest things I’ve ever seen in my entire life.
An astronomical compendium (plural = compendia) is an instrument that carry numerous devices for telling the time and performing astronomical calculations. Many compendia were made in the German lands in the late 16th and early 17th centuries. They are often beautifully engraved in gilt brass.
Typically such compendia carry a sundial, various lunar and solar volvelles, a compass, tables of latitude, and a perpetual calendar. Two characteristics are typical of the construction of these instruments: first, they were often made as lavishly as possible; second, they are ingeniously constructed, with as many instruments as possible filling the available space.
Most of the instruments on a compendium are used to simplify astronomical calculations. Many compendia have volvelles - rotating discs that show the phases of the Moon, the positions of planets, and other such phenomena.
Some compendia also carry stereographic projections. These are multi-purpose maps of the heavens, allowing many astronomical calculations to be simplified. Using these, people could determine the time of sunrise and sunset, and the position of the Sun in its annual (apparent) motion through the sky.
I wanted to share this awesome, brand new bird poster from the artists at Pop Chart Lab with you all. This large 39″ x 27″ poster features a stunning 740+ species of native and introduced birds found in North America. They are drawn *somewhat* to scale and grouped by family. Pop Chart Lab is offering 5% off for @becausebirds followers with the code: BBirds5.
But how do you keep track of all these awesome space missions? To help out,the guys at Pop Chart Lab have created this beautiful poster showing our space exploration to date. It spans all the way from 1959 to 2015, and features over 100 exploratory probes, landers, and rovers.
As you can see on the poster below, the majority of our machines never leave Earth’s orbit. There are a whole lot of crowded lines near our planet, each of which belongs to a space probe or explorer of some kind. But as you get further from Earth, there are less and less of these brave explorers, and you get to see just how far humanity has travelled into our Solar System.