✧ Southern Cross The Southern Cross is an asterism in Crux. • ⢸ ⠘⡆ ⡇ ⢀⣀⣠⠤• ⣀⣠⠤⠴⢳⠚⠉⠉ •⠒⠋⠉⠁ ⢸ ⠘⡆ ⡇ ⢳ ⢸ ⠘⡆ ⡇ • Type Asterism Constellation Crux Stars 4 More information about Southern Cross The Southern Cross might be the most important constellation in its hemisphere. Indeed, the southern half of the sky has no bright star anywhere near its pole, so there is nothing there to steer by directly. What people do instead is take the long axis of the cross and extend it about four and a half times its own length, which lands close to the pole. The cross is small, bright and unmistakable, and it appears on the national flags of Australia, Brazil, New Zealand, Papua New Guinea and Samoa. Beside it lies the Coalsack, a cloud of dust dense enough to block the light of everything behind it, which shows up as an obvious hole in the Milky Way. Etymology From Latin Reading Crux Literally the cross ┌ Greece · Ptolemy, 150 │ part of Centaurus, unnamed │ ├ Portuguese · 1500s │ Crusero, steered by on the way south │ ├ Latin · c.1600 │ Crux, given its own place on a chart │ └ English · now the Southern Cross The evolution of Southern Cross over time -50,000 years • Gacrux ⡇ ⡇ ⢸⠁ ⢸ ⢸ ⢸ ⢸ ⢸ ⡞ ⡇ ⣀⣀⣀⠤ Mimosa ⣀⣀⡤⠤⠔⠒⠒⡏⠉⠁ • ⠐•⠊⠉⠉ ⡇ ⡇ ⡇ ⢠⠇ ⢸ ⢸ ⢸ • Acrux now ⡀ • Gacrux ⢱ ⢸ ⢸⣀⣠⠤⠤⠒⠒⠊• ⣀⣠⠤⠤⠒⠒⠊⠉⠁⡇ • Mimosa ⡇ ⢇ ⢸ ⢸ ⠘⡆ ⡇ • Acrux +50,000 years ⢀⣀⣠⠤⠴• ⢀⣀⡠⠤⠔⠒⠊⠉⠉ Mimosa •⠉⠉⠁ ⢠ Gacrux •⢣ ⢣ ⠳⡀ ⠱⡀ ⠱⡀ • Acrux Over 50,000 years either way the longest side of this figure changes by 60%, and the furthest any of its stars travels is 3.8 degrees. Gacrux drifts the opposite way to the other 3, which travel together. Proper motion only: this is the shape changing, not the sky turning or the pole moving. curl 'skymap.sh/Southern%20Cross/evolution.gif' where it is tonight: skymap.sh/Southern Cross