− | Discovering asteroids is easily done because of their large proper motion|proper motions, the key to discovering near-earth objects. An object orbiting the sun in the asteroid belt between Mars and Jupiter will typically move about 10 seconds of arc over a 15-minute period. Near-earth objects will have larger proper motions both because they are closer to the earth and because, being closer to the sun, they have larger orbital velocity|orbital velocities. Generally, the closer the asteroid to the earth, the brighter it is and the greater its angular distance of movement between observations. | + | [[File: LesGoldenAsteroidDiscovery.jpg|thumb|left|175px|<small>The beginnings of the [[Near Earth Asteroid Reconnaissance Project]] was the subject of an article in <i>Compuserve Magazine</i>, which also discussed his being a writer for the Syndicated Writers’ Group reporting as a Halley’s Comet lecturer on the high seas.</small>]]Discovering asteroids is easily done because of their large proper motion|proper motions, the key to discovering near-earth objects. An object orbiting the sun in the asteroid belt between Mars and Jupiter will typically move about 10 seconds of arc over a 15-minute period. Near-earth objects will have larger proper motions both because they are closer to the earth and because, being closer to the sun, they have larger orbital velocity|orbital velocities. Generally, the closer the asteroid to the earth, the brighter it is and the greater its angular distance of movement between observations. |