Nightly, passersby peer into a 300-pound telescope he props up on a sidewalk near the French Quarter.  Then they try to figure if he painted the wispy rings of Saturn or Jupiter's huge reddish hue on the lens.

     Brown has to just about take apart his telescope to convince people that his sidewalk show is pure science, that it is nothing as suspect as the psychic stalls that line nearby Jackson Square.  But he doesn't mind. After all, he points out, Galileo had the same problem.

     Though they have lugged their telescopes around US cities for about 25 years, business has never been as brisk for Brown and other sidewalk astronomers, a loosely knit group of skywatchers largely inspired by a former monk in San Francisco who built inexpensive telescopes.

     Reasons cited for the resurgence of interest in the heavens are the availability of inexpensive but powerful telescopes, cosmic discoveries nearly monthly from NASA telescopes, and events such as this week's Leonid meteor shower.

     "People can't be amateur chemists, they can't be amateur physicists, but they can be amateur astronomers," said Mario Motta, a member of Amateur Telescope Makers of Boston.

     Motta's group has been overwhelmed this year with requests to hold "star parties," where telescopes are set up in an open area for people to peer through as a host lectures about sights in the night sky.  One such party, in a darkened Lynnfield middle school parking lot earlier this month, attracted 250 people.  Five years ago, the group would get three or four requests annually for the parties; this year there have been more than 30 requests.

     Astronomy publications are also seeing increased circulation:  Cambridge-based Sky & Telescope Magazine sold 73,000 copies in 1987; now its monthly circulation is 126,000.  Telescope makers and sellers say sales are booming, too.  The Telescope Store / Earth Treasures in Keene, N.H., sold about 300 telescopes last year; four years ago, it sold about 20, said owner David Tong.

     Astronomers say that a recent revolution in telescope design that put computerized tracking equipment and powerful optics within reach of family budgets has helped fuel the interest.

     "You don't have to know where to look in the sky anymore," said Ron Dantowitz, astronomy educator at the Charles Hayden Planetarium in Boston.  "You just click on a button or mouse and the telescope will find what you're looking for."

     Power and complexity still come at a price, Dantowitz said, but the same amount of money five years ago will buy a much better telescope today.

     "A few hundred dollars can get you a pretty good telescope," he said.  "But I often tell people that a book and a good pair of binoculars is a good place to start."

     Dantowitz said amateur astronomy has never been more popular, thanks to the availability of new information on the Internet and elsewhere.

     "The public is really into it," he said.

     Meanwhile, school districts in Arlington, Needham, and other Boston suburbs are hosting moonrise get-togethers after dinner to teach children, for example, that Betelgeuse in the Orion constellation is a red giant star, not a movie starring Michael Keaton.  Educating students about the stars also leads to lessons about how ancient mariners learned navigation, and how some cultures named and used the constellations in everyday life.

     "With [astronomy], it's not only science we can teach; we do mythology and Native American studies.  There are a lot of different directions you can go," said Robert Simmons, a K-6 Lynnfield mathematics and science curriculum specialist.  "Kids may not always see other things in science.  But they go out, they look at the stars."

     The Lynnfield school district just purchased a portable planetarium, an inflatable 20-foot dome that accommodates about 25 children at a time who can watch the correct positions of the stars and planets projected on the interior.  The domes, which can also be rented, have become popular, inexpensive ways to introduce youngsters to the stars without having to transport them to city observatories.

     Astronomy did not start out as a street science.  Often reserved for academics and physicists, the heavens were wondered about, but barely seen in detail; telescopes were too bulky and expensive and there were few programs for the public.  And while amateur telescope societies have dotted the landscape since the early part of this century, most programs were reserved for elite club members.

     After the Russian satellite Sputnik was launched in 1957, however, public interest in the "space race" skyrocketed.  The US government began pouring money into space exploration, and people began looking upward.

     Meanwhile, a former monk, John Dobson, took to the streets of San Francisco in 1967 teaching the public how to build inexpensive telescopes, even using junkyard finds like roof shingles and portholes from ships.  Eventually, the "Dobsonian" method of telescope-making was copied by commercial dealers, making the instruments more accessible to the public.

     Dobson also helped form the Sidewalk Astronomers Association, dedicated to introducing novices to the skies.  Almost weekly, the group picks a San Francisco site and a time and invites the public to show up and learn about planets, globular clusters, and the Milky Way.

     Since Dobson's sidewalk group was formed, similar associations have cropped up in Toronto, Fort Worth, and Los Angeles.  New England does not host a sidewalk astronomer club per se, but the dozen or so astronomy clubs in the region are dedicated to the same purpose:  increasing public awareness of the heavens.  And professional astronomers are doing the same.

     "The least we can do is to share what we know with the general public," said Eric Chaisson, director of the Wright Center for Innovative Science Education at Tufts.  He has started several astronomy nights and he lectures at universities and observatories in the region.  "We're all sort of sidewalk astronomers, just in a more organized way. The same philosophy is there."

     Brown likes his method better - showing off the stars to people who would not attend a star party or astronomy lecture.  Brown, 51, the son of a New Orleans musician, (Pud Brown) first became interested in the skies after he finished a three-year stint in Vietnam.  He took his last $500 and bought a telescope.  He eventually meandered back to New Orleans, where he has been toting his telescope for 25 years.

     While he is no astrophysicist, Brown can pick apart the sky for just about anyone.  Every clear night, he sets up outside the Cafe du Monde on Decatur Street in the city's French Market. A bucket off to the side collects donations - a dollar or two a peek, $10 for a galaxy tour.

     Vincent Shapiro, 43, of Cleveland, walked past Brown's set-up two times before venturing over to peer in the eyepiece.  He wrinkled his face at first, curious if he was being had. But Brown pointed Shapiro's naked eye to Saturn and Jupiter and then aimed the telescope there.

     "You just don't think you're going to see anything that looks so perfect," Shapiro said. "It looks like a sticker on the lens."

     Many customers are initially skeptical that a star or planet can be seen against the bright backdrop of New Orleans' night life.  But Brown puts a small piece of cardboard in front of the eyepiece that helps block interfering light.

     While you can't see everything, you can see enough.

     "It's all real," said Brown. "It's all right there in the sky."