(FORTUNE Magazine) – Two things occurred just past noon on July 9: a full moon and a stock market free fall. Coincidence? Not to Henry Weingarten, founder of the Astrologers Fund Website, www.afund.com, who says a full moon during market hours is a sure sign of trouble. In fact, he says stargazing investors can call market movements, mergers, and company performance. His site has attracted more than 5,000 subscribers, each of whom pays up to $300 a year to read his newsletters, Investing by the Stars and Wall Street, Next Week (don't laugh: Microsoft's vaunted slate.com has only 23,000 subscribers and charges a mere $19.95). Even stalwart Wall Street types concede that Weingarten's methods seem to have validity. "Some peaks and troughs in the market have correlated with lunar eclipses," says Peter Canelo, U.S. strategist at Morgan Stanley Dean Witter.

Using astrological charts, Weingarten also tracks major events in companies' lives. Each firm's sign is determined by its incorporation date. For example: Disney and GM are Libras; Coke is a Virgo; and IBM is a Taurus. Reading AT&T's chart--Ma Bell is a Pisces--Weingarten foretold problems with its bid for TCI on June 24. The day after it was announced, Neptune converged with Saturn--a portent of disaster.

So how good is Weingarten? Sure, he's had some gaffes. at the end of June, for example, he forecast that Microsoft stock would drop 10%. (It's now up 15%.) But in some cases he's been an impressive soothsayer. He called the Asian crisis last September when a lunar eclipse--an indicator of instability--occurred over the continent.

Herewith, Weingarten's summertime forecasts:

--The market will experience a minicrash because of one solar eclipse and two lunar eclipses.

--There's good news for Intel. The company is moving from Saturn's influence to Jupiter's, which means positive news throughout the fall.

--The next big crash will occur on May 28, 2000, when Jupiter moves away from Uranus to converge with Saturn. Today's Jupiter/Uranus combo is a sign of suspended reality (explaining the Dow's sky-high P/E). When it ends, reality returns, and the market will crash back to earth.

--Katrina Brooker