Two asteroids are passing close to Earth today but are not likely to pose a threat. US space agency NASA says, both will come within the Moon's orbit. One of them, estimated at six to 14 meters in size, is set to pass about 79,000 kilometers away. The other asteroid is believed to be 10 to 20 met res in size and is expected to pass within 248,000 kilometers of Earth. Both objects should be observable at their closest approach with moderate-sized amateur telescopes.