• CAPE CANAVERAL, Fla. (AP) -- A 150-foot asteroid hurtled toward Earth's backyard, destined Friday to make the closest known flyby for a rock of its size.
• NASA promised the asteroid would miss Earth by 17,150 miles, avoiding catastrophe. But that's still closer than many communication and weather satellites; scientists insisted these, too, would be spared.
• Asteroid 2012 DA14, as it's called, is too small to see with the naked eye even at its closest approach around 2:25 p.m. EST, over the Indian Ocean near Sumatra.
• The best viewing locations, with binoculars and telescopes, are in Asia, Australia and eastern Europe. Even there, all anyone can see is a pinpoint of light as the asteroid zooms by at 17,400 mph.
• As asteroids go, DA14 is a shrimp. The one that wiped out the dinosaurs 65 million years ago was 6 miles across. But this rock could still do immense damage if it struck, releasing the energy equivalent of 2.4 million tons of TNT and wiping out 750 square miles.
• Scientists are certain it won't impact Earth. And chances are extremely remote it will run into any of the satellites orbiting 22,300 miles up.
• Most of the solar system's asteroids are situated in a belt between the orbits of Mars and Jupiter, and remain stable there for billions of years. Some occasionally pop out, though, into Earth's neighborhood.
• The flyby provides a rare learning opportunity for scientists eager to keep future asteroids at bay -- and a prime-time advertisement for those anxious to step up preventive measures.
• "We are in a shooting gallery and this is graphic evidence of it," said former Apollo astronaut Rusty Schweickart, chairman emeritus of the B612 Foundation, committed to protecting Earth from dangerous asteroids.
• Schweickart noted that 500,000 to 1 million sizable near-Earth objects -- asteroids or comets -- are out there. Yet less than 1 percent -- fewer than 10,000 -- have been inventoried.
• Humanity has to do better, he said. The foundation is working to build and launch an infrared space telescope to find and track threatening asteroids.
• DA14 -- discovered by Spanish astronomers last February -- is "such a close call" that it is a "celestial torpedo across the bow of spaceship Earth," Schweickart said in a phone interview Thursday.

(Continued on page 29)