As the first images are released from Messenger's flyby of the innermost planet, previous ground-based observations are proving to be surprisingly accurate.

Mercury is a rewarding challenge for planetary astrophotographers, as this amazing image by Massachusetts amateur John Boudreau demonstrates.

Amateurs are observing this elusive planet more successfully than ever before; try spotting it yourself.

To compare what you see on Mars with a map, you need to know which side of the planet you're looking at. Our handy Mars Profiler tells you that and more, for any date and time.

Viewing the solar system¹s largest planet can be more than fun — even with a modest telescope, you can make observations of lasting scientific value.

Click here for printable tables showing when interesting events happen on and around Jupiter.

With help from our interactive JavaScript utility, you can always tell which of Jupiter's four largest satellites is which.

Now you can calculate the dates and times (local and Universal Times) when the center of the Great Red Spot should cross Jupiter's central meridian, the imaginary line down the center of the planet's disk from pole to pole.

With Saturn putting on a fine show this year, you'll want to explore the ringed planet at every opportunity. Here's what to look for.

Click here to find printable data on the positions of Saturn's rings and planets.

With help from our interactive JavaScript utility, you can always tell which of Saturn's brightest moons is which.

Have you seen the two big planets that weren't known in ancient times?

Our handy JavaScript utility can help users of moderate to large telescopes find Neptune's largest satellite.

Our handy JavaScript utility can help users of large amateur telescopes find as many as five Uranus's brightest satellites.

Not so long ago, astronomers thought only a few dozen satellites orbited the planets of our solar system. Today the total count tops 160!