What was going on when I was born?

A Federal district judge in Mississippi was indicted today on charges of accepting oil-well royalties as a bribe and lying to a Federal grand jury about his influence in a drug case. The grand jury accused Judge Walter L. Nixon Jr., chief judge for the Southern District of Mississippi, of accepting the royalties in exchange for ''official acts'' on behalf of a businessman whose son was later arrested on drug smuggling charges. Judge Nixon, the third sitting Federal judge in the nation's history to be indicted for activities related to judicial duties, pleaded not guilty and was released without bail. He immediately took a paid leave of absence.

''A comprehensive test ban will not reduce the number of nuclear weapons in the world by one.

An article in Metropolitan Report yesterday about a report by a Columbia University trustees committee on the university's investments in companies with operations in South Africa gave the incorrect date of the committee's formation. It was formed in May 1984.

The Reagan Administration said today that ''a sharp deterioration'' in the situation in South Africa had caused an erosion of confidence in that country's financial stability, and that moves toward easing some apartheid restrictions had ''stalled.'' In a briefing for reporters called to deal with some seeming contradictions in the Administration's policy toward South Africa, a senior State Department official said the efforts by the South African President, P. W. Botha, to defuse the tensions and violence had only worsened the situation. The official cited the failure of a Botha speech on Aug. 15 to win the support of the country's black leadership. Urging Mr. Botha to make a clear-cut commitment to end apartheid, the official said, ''What is clearly needed is talking and negotiating and constructive signals to build a better climate, not jailing and beating and bombing and burning.''

Friday WORLD'S FAIR RETROSPECTIVE Picturephones, spanking new Ford Mustangs and visions of a future filled with moon buggies and factories on wheels - in short, the sights and sounds of the 1964-65 World's Fair in Flushing Meadows - would hardly seem like history to many who were there. But 20 years later, an exhibition of photographs, films, music and paraphernalia from the fair demonstrates the many ways in which the nation has changed since the days just following the New Frontier. The retrospective, entitled ''The Mighty Fair,'' is presented by the Flushing Council on Culture and the Arts and is open from 10 A.M. to 5 P.M. today and tomorrow and from 1 to 5 P.M. Sunday at the Flushing Gallery, 136-73 41st Avenue (between Main and Union Streets), in Flushing, Queens. Admission is free. Information: (718) 463-7700.

Surgeons at the University Medical Center in Tucson yesterday implanted an artificial heart in a 25-year-old man to sustain his life until they can find and then transplant a human heart. It was the first federally authorized use of an artificial heart as a bridge to a human heart transplant. The operation to implant came 13 days after the head of the transplant team, Dr. Jack G. Copeland, received permission from the Food and Drug Administration to use a Jarvik-7 artificial heart for temporary use. He did a similar procedure last March without Government approval, setting off vigorous debate on ethics.

LABOR DAY weekend is, without a doubt, America's most bittersweet three-day holiday. With it, the warm, playful rhythms of summer end and the cooler, more serious days of autumn begin. But although the holiday lacks Memorial Day's anticipation of summertime fun and the joyful laziness of the Fourth of July, Labor Day weekend signals the last bash of summer. And this year's citywide festivities are bigger and more varied than ever. Parades and fairs celebrating America's labor and immigrant heritage, a host of outdoor art shows and concerts ranging from rock-and-roll on the beach to a fireworks-spangled Philharmonic extravaganza in Central Park are among the ways New Yorkers can enjoy the holiday that began in their city in the late 19th century. Kicking off the weekend, the city's parks will resound today with music to suit almost every taste. At Lincoln Center's Damrosch Park, the Harmonie Wind Ensemble will perform Handel's ''Royal Fireworks Music'' in honor of the composer's 300th birthday. The concert is one of more than a dozen Lincoln Center Out of Doors events this weekend. It begins at 8:15 P.M. and will be appropriately augmented by a display of sparklers and 300 balloons (story on page C4).

The Board of Education has begun a $2.25 million program to restore and expand sports programs eliminated or reduced a decade ago during the city's fiscal crisis. The effort includes new sources of money for 50 high school varsity sports teams and the creation of 375 junior varsity teams. It follows the approval by the City Council this year of an increase of nearly 50 percent in the Board of Education's budget for athletics. ''We've undertaken a major initiative in the expansion of sports,'' said the superintendent of operations for high schools, Arthur Auerbach. ''We're talking about a lot of money going into this.''

Middle South Utilities, the nation's fifth-largest utility holding company, said yesterday that it would omit its quarterly dividend for the first time since it was organized 36 years ago. State regulators have denied the company's request for rate increases to pay for its Grand Gulf nuclear power plant, in southwestern Mississippi, but analysts said yesterday that the dividend omission could speed efforts to solve the problem. The regulators have said that they would not grant rate increases as long as the dividend was paid. ''This may be just the thing Middle South needs to show regulators that they are doing their part to resolve the crisis,'' said Thomas P. Halligan, a utility analyst with Duff & Phelps Inc. of Chicago.

The Gannett Company agreed yesterday to buy the Evening News Association for $1,583 a share, or a total of about $717 million, in a cash merger, the companies said. The decision ended weeks of speculation about the fate of one of the leading media companies, which has been controlled by the Scripps family for 112 years. Jack Kent Cooke, the entrepreneur whose holdings range from real estate to ranching, also bid but lost, according to sources close to the talks. The winning bid is $333 a share higher than a hostile tender offer by L.P. Media, which is owned by Norman Lear and A. Jerrold Perenchio, two Hollywood producers.

Sales of new single-family houses rose 1.4 percent in July, to the highest level in almost two years, the Government said yesterday. It also revised upward its figures for April, May and June, showing a much stronger performance than previously reported. Sales in June, reported a month ago as a drop of one-tenth of 1 percent, actually rose 2.2 percent. The Commerce Department and Department of Housing and Urgan Development said the upward revisions stemmed from late reports containing stronger results than the earlier data.

One day early this month in the midst of an otherwise lazy summer afternoon the stock market was grabbed by an undertow that pulled the Dow Jones industrial average down 21.73 points. And last week, stocks bounded up 11 points one day and down 11 on another for no apparent reason. The mysterious force behind the moves, it turned out, was a relatively new phenomenon on Wall Street called program trading. The term refers to programs of orders from institutional investors and other professional traders to buy or sell shares in 100 or more large companies that are a surrogate for the broader Standard & Poor's index of 500 stocks. Such programs are often initiated by arbitrage opportunities when the current value of stocks reflected by the S.&P. 500 and the price of a stock index future on that index are out of line. An index future is a contract between two parties that allows an investor to bet on the general direction of the market over a short period of time.