The waxing crescent Moon passes close to three planets this week: Mercury, Venus, and Jupiter. All of them lie close to an imaginary line in the sky called the ecliptic.

This is a dramatic week for planet watchers. In the east, Mars is at its brightest and closest to Earth for 2012. On the opposite side of the sky, Venus and Jupiter form a spectacular pair.

This week the night sky’s six or seven brightest objects are all visible 45 minutes after sunset, something that won’t happen again for decades.

Orion is center stage in the south as the sky grows dark. This constellation contains 7 of the sky’s 100 brightest stars. And most of Orion’s main stars are physically related.

Mars, the Red Planet, is beginning to appear in the evening sky. In many ways, Mars is the planet most like Earth, with deserts, dust storms, and maybe even running water on rare occasions.

This week Eros, the grandaddy of all near-Earth asteroids, is making its closest approach to Earth since 1975, just 16.6 million miles away. That make it our second-closest neighbor after the Moon.

Learn how Perseus rescued Andromeda, and find out how and why Queen Cassiopeia is doomed to rotate forever in the sky.