A Style Plus article yesterday incorrectly stated the distance between Saturn and Earth. The correct distance is about 800 million miles. (Published 8/6/87)

Take solace after sweltering in Washington's hottest July ever. The sun is heading south.

This is a cross-quarter period, which means the sun is halfway between the Tropic of Cancer and the Equator, and we are halfway through summer. When the sun reaches the Equator late in September, it marks the first day of autumn and the return of good sleeping weather.

Meanwhile in these August nights, visions of Saturn will melt your soul. Saturn has turned nearly full face toward us. Look to the west, in the middle of the sky in the early evening. Although our large, gaseous planetary brother is about 900,000 miles away, a moderately strong telescope can clearly define Saturn's rings. Otherwise, the planet looks like a bright star to the naked eye.

Also, in these waning summer days, hope that the bright moon doesn't fully obscure the Perseid meteor showers on Aug. 11-13. The moon turns full on the 9th and it will probably be powerful enough to overcome shower sightings. The Perseids, one of the hottest showers of the year, can produce as many as 50 meteors an hour, putting on a nice cosmological show.

Meteor showers are comet debris. As Earth passes through this harmless cometary garbage on it's annual tour around the sun, luminous comet remnants zip across the night sky.

The visibility for the Summer Triangle is certain. Look high overhead in mid-evening. Forming an almost perfect isosceles triangle, the stars Deneb, Vega and Altair move toward the northwest part of the sky. The triangle's tip, Altair, points south. The extremely bright Vega is in the northwest and Deneb is in the northeast part of the figure.

Although Deneb seems to be the dimmest star in the triangle, it actually is the most powerful. Deneb is 1,600 light years from Earth, but the star is 63,000 times brighter than our own sun. Because of its proximity to Earth -- a mere 27 light years away -- Vega seems to be the brightest in the triangle. It is, however, only 50 times brighter than the sun.

With stops in Bangkok, Singapore, Borneo and Hong Kong, traveling 25,000 miles to see a total solar eclipse will have added adventure next year.

"We're getting a lot of new people because the ports-of-call are very interesting," says Virginia Roth of World of Oz travel agency in New York City.

The eclipse's path of darkness crosses through the Celebes Sea on March 18. Its totality lasts three minutes and it will not be visible from Washington. Roth, who specializes in scientific expeditions, has chartered the Royal Cruise Line's "Golden Odyssey" to hunt the eclipse.

For more than 15 years Roth has assembled astronomy tours, while more recent start-up agencies have faded with the departure of Comet Halley.

For this tour's 18-day cruise, Roth has cast an astronomical all-star team to enlighten the travelers. Hugh Downs, of ABC-TV's "20/20"; Leif Robinson, editor of Sky & Telescope magazine; Leon Jaroff, science editor for Time magazine; Dr. Fred Hess of the Hayden Planetarium in New York, and Robert Little, an astrophotography expert will offer on-board lectures and guide passengers through the eclipse.

The cost from Washington is around $3,400, based on current air fares.

Sky gazers with smaller budgets may be interested in another trip the World of Oz agency is offering: Next August, the Astronomy Island Cruise sets sail from New York to Bermuda. The trip will feature science writer Isaac Asimov as a guest lecturer; prices for this week-long excursion begin around $1,000 per person, depending on cabin accomodations, Roth says.

For more information, call the World of Oz at 800-248-0234.

Closer to home:

Aug. 8-9: Bob Slater of the Goddard Space Flight Center will show two award-winning NASA films at the Goddard Visitor's Center. "The Time of Apollo" chronicles the Apollo space program, and "Apollo 15: In the Mountains of the Moon" features the fourth lunar landing mission. The films start at 1 p.m. each day, admission is free.

Aug. 23: Special public tours of Goddard's Test and Evaluation Facility. Meet at the Visitor's Center. Tours run between 11 a.m. and 3 p.m., on the hour. Admission is free.