This time of year it's always fun to look for a morning "Christmas star" in the east just before sunrise.

The trouble is that this time of year there aren't any really bright stars in the early morning Pennsylvania sky. The only one that comes close is the moderately bright star Vega, but in the predawn sky it's already pretty high up in the northeast. If there is a Christmas star to be seen it's usually not a star but rather a planet, or a conjunction of planets.

The original Christmas star sighted in the Bible could have very well been a supernatural event. If not, the original Christmas may have been an exploding star, otherwise known as a supernova that appears as a very, very bright star for weeks and weeks, if not even longer.

It could have also been a bright conjunction of two or more planets. If it was a conjunction, it's difficult to tell which ones may have produced the Christmas star, since the exact year of Christ's birth is uncertain.

The best candidate for Christmas "star" (or planet) in 2005 is the planet Jupiter, the largest planet in our solar system. Look for Jupiter in the low southeast skies between 6 a.m. to 7 a.m., before morning twilight really starts to kick in.

You can't miss Jupiter; it's the brightest star-like object in that part of the sky. In fact, we have a little bonus this year in our celestial Christmas stocking. The waning crescent moon and Jupiter will be putting on a nice little show the next few mornings, and the moon will slide eastward past Jupiter from morning to morning.

Early Sunday morning, you'll see the moon about 20 degrees to the upper right of Jupiter, or about two of your clenched fist-widths at arm's length.

On Monday, the moon and Jupiter will be in a really tight celestial hug, separated by less than 10 degrees.

On Tuesday morning, between 6 and 7 a.m., the crescent moon will be a lot thinner but still very close to Jupiter, only 7 degrees to the lower left of the planet named after the king of the old Roman gods.

Looking at Jupiter with even a small telescope reveals cloud bands that seem to be diagonally orientated to our view. These are made up mainly of methane and ammonia, swirling at speeds in excess of 1,000 mph over the "surface" of the planet.

Jupiter is more or less just a giant ball of hydrogen and helium gas, over 88,000 miles in diameter. Our Earth is only about 8,000 miles in girth.

When you look through your telescope, you'll also see up to four little stars on either side of Jupiter. These aren't stars, they are Jupiter's four largest moons, circling the big planet in periods of two to 17 days.

Don't be too discouraged if the image seems a little fuzzy through the telescope. Because it's so low in the sky, you and your telescope have to plow through a lot more of Earth's blurring atmosphere than if Jupiter were high in the sky. The best time to observe Jupiter will be next May when it's at its minimum distance to Earth for the year.

Through a telescope, or even a good pair of binoculars, the moon is always some kind of wonderful, even when it's down to a crescent. The sweet spot is along the line between the sunlit part of the moon and the darkened part of the disk. That line is called the terminator and that's the best place to explore the moon, maybe with that new Christmas telescope.

The sun's light hits that part of the moon at such a low angle that it allows you to see a lot more detail on the lunar surface. Because of the low shadows, the crater walls and mountain peaks really show up. Sometimes you can even see high mountain summits peaking above the shadowed part of the surface.

Another thing to watch for when the moon is in its crescent phase is the phenomena of "Earthshine." That's when you see not only the sunlit crescent slice of the moon's disk but you can see the rest of the disk as well, bathed in a soft gray light. That pale light on the moon is sunlight that's bounced off the highly reflective Earth, and then onto the Moon. Call it second-hand sunlight.

Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis and author of the new book, "Pennsylvania Starwatch," available at bookstores and at his Web site www.lynchandthestars.com