... The Sun in Three Dimensions . ... What does the Sun look like in all three spatial dimensions? To find out, NASA launched two STEREO satellites to perceive three dimensions on the Sun much like two eyes allow humans to perceive three dimensions on the Earth. ... The Milky Way flows through this celestial expanse whose wonders also include the closest star system to the Sun, Alpha Centauri, and the largest globular star cluster in our galaxy, Omega Centauri (aka NGC 5139). ...