You really have to hand it to the early explorers. They sailed most of the globe without the ability to accurately navigate (from Latin roots meaning "steer the ship"). They often had a pretty good idea of their latitude (north-south position), but the east-west position, the longitude, was mostly guesswork until the invention of the chronometer ("that which measures time") in the late 18th century. Learn more. If they were traveling east across the Atlantic, for example, they not only didn't know how far they'd gone, they also didn't know how close they were getting to the next shore. If they over-relied on the celestial bodies for guidance, they risked disaster-- from dis "wrong" and aster "star," the idea of a calamity caused by an inaccurate sighting of a star or planet.
But the sailors were going on more than dumb luck. They would spot things floating in the water which indicated that land may be near. And they would watch for birds, which leads me to auspicious. The au root maps to the Latin avis "bird," and spic is a variant of spec "view, look, see." Yes, the story of auspicious is the spotting of birds before land-- a good omen, a favorable outlook.
Birds have long been an important source of information. In ancient times an augur was a prophet or soothsayer, one who interpreted omens from the flight patterns of birds. Now we mostly use augur as a verb meaning to portend a good or bad outcome. And then there's auger "that which bores into the future." (Just kidding. I made that one up). To predict future events is also to augment ("make greater") the collective knowledge of what is coming. If your track record is sound, folks might even see you as an august authority, or a respected author. Each of these words carry the idea of prognostication ("knowing before, foretelling"). To be under the auspices ("sponsorship, support") of something is to have favorable guidance, to be steered clear of bad outcomes. And did you know an inauguration is etymologically the inducting into office of the bird-watcher in chief? Check out this piece by Brian Kimberling.
But let's cycle back to navigation. It wasn't all disasters. In fact, one legend from the Age of Exploration suggests the word America was born of a successful estimation of longitude. Here's the story: Amerigo Vespucci, an Italian mathematician, astronomer, and navigator, set sail across the Atlantic in 1499. He brought with him an almanac (from Arabic al-manakh "calendar") produced by astronomers in Ferrara, Italy and containing annotated positions of stars at exact times. It just so happened that a Mars convergence (from Latin roots meaning "a turning together") was predicted in Ferrara at exactly midnight on August 23rd, 1499. On that date, Amerigo, now on the coast of what later became Brazil, began making celestial ("from the sky") observations. He measured the stars to determine the exact local time and then waited for the moon to cross Mars. Based on these observations, he determined the time difference from Ferrara and calculated an accurate enough longitude to prove that he was on a new land, nowhere near India as Columbus had long maintained. For his great discovery, cartographers ("writers of charts, maps") labeled the new land America, after the feminine Latin version of Vespucci's first name, and King Ferdinand made him chief navigator of Spain.
It pays to keep an eye on the sky!