The dispatcher's name is Rita, and she speaks in the dulest tones of deepest Brooklyn. But the hacks in Voyager's "Planetary Taxi" are ready to whisk passengers to the farthest reaches of the solar system. This Macintosh CD-ROM is an astronomy lesson cleverly disguised as an interplanetary quiz show. Drivers pick up fares who ask to go to the planet with, say, water and ice (Earth) or the highest gravity (Jupiter). For players who don't know Io from Europa, there's an easy-to-use on-screen reference panel. "Planetary Taxi" is also a great introduction to electronic modeling; planets close to the sun whiz by, but it's a long haul to Neptune. It is most likely to appeal to kids in the fourth grade and up (as well as stargazing adults). One caveat: "Planetary Taxi" works best with a fast CD-ROM drive. Otherwise, you'll feel like you're stuck in a cosmic traffic jam.