21 100 thousand light-years We look face-on directly at the Milky Way spiral, A hundred billion stars mutually bound by gravity encircle the centr wn sun swings with the rest in dignified passage clockwise about the distant galactic nter,once every three hundred million years. External galaxies akin to our own are scat tered throughout space as far as we can see. They too rotate slowly as they drift
1020 Clouds of stars and with patches of darkening dust, mark the slow-changing spiral patterns of the isk. Our distant sun cannot be seen here but it is in the center of the image, near t
10 In by the old watchers of those who first gathered stars into constellations, lies within this square, our own galact neighborhood. There are many other stars as well, too faint for the eye to see
10 A skyful of distinct stars: One among them, central, but too faint to pick out, is our sun The star Arcturus, Prominent in the northern sky of earth,shines Arcturus is in trinsically more luminous than our sun, and here we are nearer to it as well