As you ring in the new year, consider making a resolution to commit random acts of observing throughout 2010. You don't need a fancy telescope to observe the stars, just your eyes and clear skies. Look up occasionally and get to know your universe.

SIRIUS MATTERS

The brightest star in the night sky is Sirius, shining at a magnitude of -1.47. Sirius is bright because it is very hot and relatively close to Earth. Sirius is important in Polynesian celestial navigation since it passes through the zenith in Hawaii.

To find Sirius, follow the three stars in Orion's belt in a line to the southeast. Sometimes called the Dog Star, Sirius marks the nose of Orion's hunting dog in the constellation Canis Major. To visualize the dog, look for two fainter stars that form a triangle with Sirius and mark the dog's ears, then follow a line of stars from Sirius that outline the dog's long back and tail. Two more nearby stars mark the dog's front and back legs.

The ancient Greeks noticed that Sirius rose just before dawn during the hottest part of the year, which led to the phrase “;dog days of summer.”;

MARS IN LINE

On Jan. 29, Mars reaches opposition with Earth, making it a great time to observe the red planet. In astronomy, opposition refers to the moment when a planet farther from the sun than Earth appears opposite the sun in the sky. In this case, Mars, Earth and the sun form a line in space, with Earth at the center. At opposition, Mars is at its brightest and is visible throughout the night. At apparent magnitude -1.27, Mars appears nearly as bright as Sirius. On the night of Jan. 29-30, look for the reddish-orange Mars near the full moon. The light from the full moon will dim Mars somewhat, so keep your eye on the planet over the next few nights. As the moon pulls away from Mars, there will be less moonlight to interfere with the planet's brightness.

SO CLOSE YET SO FAR AWAY

On Saturday Earth reached perihelion, the closest point in its orbit around the sun. Earth's orbit is not perfectly circular, but is actually an ellipse, which means that its distance from the sun varies throughout the year. At perihelion Earth is approximately 91.4 million miles from the sun, whereas at aphelion—the farthest point in Earth's orbit—Earth is 94.5 million miles from the sun. In 2010 Earth's reaches aphelion on July 6. It might seem strange that Earth is closest to the sun during winter and farthest away in summer, but keep in mind that the seasons are determined by Earth's axis tilt, not its distance from the sun.