At the same time, he has extended most tables of the book at least 15 years further into the future. To many skywatchers it is an observing guide for the better part of a lifetime. All the most spectacular planetary conjunctions are listed here. The dates of greatest elongation of Mercury and Venus from the Sun tell when these two inner planets are most readily viewed with a telescope. For an outer planet like Mars, the opposition date is very close to the time it presents the largest possible disk for telescopic study.
Oppositions are also good times for spotting the brighter asteroids in binoculars.
Those who watch Jupiter's moons dip in and out of eclipse will enjoy page 58 of this book, listing the intervals when Callisto avoids the giant planet's shadow entirely. At the endpoints of these intervals, rare partial eclipses may be seen. No ordinary almanac is much help with the exact times to look for these events because they depend so much on the observer's geographic location. The star may wink out in Montreal almost an hour after it does in Denver, or the Moon may miss the star completely. Commercial software can be a poor guide too, as I discovered a few days before a recent occultation of Spica.