Looking for the perfect Valentine's Day gift? Some deep-sky gems come stargazers' way this week, just ahead of the romantic holiday, thanks to Earth's moon pointing the way.
Zodiacal light. At about an hour after sunset on Monday, February 9, and the rest of this week, keen-eyed sky-watchers in the Northern Hemisphere can hunt down one of the most elusive of astronomical phenomena, zodiacal light.
A pyramid-shaped nimbus of light filling the sky, zodiacal light is caused by sunlight reflecting off the cosmic dust between the planets. The best time to catch this ghostly light is about an hour after sunset, when looking toward the western horizon from the dark countryside.
How did interplanetary space become dusty enough to diffuse sunlight and set the sky aglow? The celestial phenomenon results from the reflection of billions of dust-size particles left behind in interplanetary space after the planets formed around the sun some 4.6 billion years ago.
Moon and maiden. Late at night on Monday, February 9, take a peek at the rising moon, which will point the way to the 250-light-year-distant, blue diamond star, Spica, in the constellation of Virgo, the Maiden.
Sparkling Spica will appear to be within only 6 degrees of the moon, slightly more than the width of your fist at held at arm's length against the sky.
Ranked as the 15th brightest star, Spica is actually a double star, whose two stellar orbs orbit each other only 11 million miles (17.7 million kilometers) apart, more tightly than Mercury orbits the sun in our solar system. The two stars are so close together that their mutual attraction has pulled them into the shape of eggs.
Moon and Saturn. Early risers on Thursday, February 12, can see the waning gibbous moon point toward Saturn and the bright orange star Antares in the predawn hours.
By Friday morning, the moon will have jumped to the opposite side of Saturn. The cosmic duo and the 600-light-year-distant Antares, hanging below, will form a distinct triangular pattern. Train your small telescope on the real "Lord of the Rings" and check out its retinue of moons.
Moon and snow globe. Sky-watchers in the early morning hours of Saturday, February 14, can catch sight of the giant globular star cluster Messier 9, hovering at the edge of our Milky Way galaxy.
Shining at magnitude 7.7, this cluster of hundreds of thousands of stars appears as a tiny, hazy ball when viewed with binoculars.
However, a small backyard telescope will resolve some of the outer stars surrounding its core. While Messier 9 lies some 26,000 light-years away, it appears only 2 degrees to the upper right of the moon, a distance equivalent to four lunar disks set side by side.
Moon and jewel box. By Sunday, February 15, Earth's natural satellite will take its place next to another deep-sky treasure called Messier 25. This storied collection of stars was discovered around 1745 but went uncataloged; it was rediscovered in 1866.
The open star cluster, shining at magnitude 4.6, looks like a fuzzy spot to the naked eye when seen from a dark location. But binoculars will reveal about three dozen stars huddled together, all of them sitting some 2,000 light-years away from Earth.