PASADENA, Calif. (AP) _ The sights and sounds of Mars will be no farther away than any computer plugged into the Internet once NASA's Polar Lander is in operation Friday. Virtual tourists visiting NASA's Web site will find pictures, weather reports, science data and the first sound clips ever beamed to Earth from 157 million miles away, said Kirk Goodall, Web page engineer at Jet Propulsion Laboratory. ``It's hard to say that it will be the Internet's biggest event ever, but it certainly will be right up there,'' he said. More robust computers should prevent the traffic jams that made it difficult to access sites during the landing of Mars Pathfinder, which attracted a record 33 million hits a day over the 1997 Independence Day weekend. Several million hits are expected in the first days after the landing near Mars' south pole, with at least 1 billion during the entire three-month mission. A hit is counted each time a file such as a graphic or text is accessed on a Web site's host computer. In addition, Polar Lander's pages will be duplicated at 20 mirror locations around the world. Improved technology now allows browsers to be automatically redirected to mirror sites with the least traffic. ``I think we're probably in pretty good shape,'' Goodall said. ``If we have any problems, we have other mirror sites we haven't told the world about yet.'' Improvements over the Pathfinder presentation also include streaming video from NASA TV, a continuously updated panorama of the operations room at JPL and a movie of the descent made up of shots made by a camera mounted at the bottom of the lander. By Saturday, sound clips recorded from a small microphone mounted on the lander are expected to be available on the Web from the Planetary Society, a private space advocacy group that funded that part of the mission. Web sites offering information on Mars and the Polar Lander mission: _ JPL's main Mars site will post the latest pictures and updates throughout the 90-day mission: marslander.jpl.nasa.gov or mars.jpl.nasa.gov/msp98 _ JPL's home page has links to the latest Mars projects as well as probes sent to other planets over the last 20 years. www.jpl.nasa.gov _ JPL's Mars Educational site includes activities for children and teachers. In one section, pages can be printed, folded and glued to create a model of the Mars Polar Lander: marsnt3.jpl.nasa.gov/education/index.html _ The University of California, Los Angeles, where the primary science team is based, offers a site focusing on experiments aboard the Mars Volatiles and Climate Surveyor payload: mars.ucla.edu _ The Planetary Society will mirror JPL's site and offer its own content in conjunction with its PlanetFest '99 gathering at the Pasadena Center: planetary.org _ The Mars Society, which advocates human exploration of the Red Planet, will mirror JPL and offer its own content: www.marssociety.org