September 24, 1985

Chalk up another entrant in the financial services derby. It is the Metropolitan Life Insurance Company, once the epitome of a narrowly focused lumbering giant in one of the most conservative sectors of the financial world. Now it is shucking off its reputation as the ''Old Lady of One Madison Avenue'' as it revs up to take on the likes of the American Express Company, Sears, Roebuck & Company and the Prudential Insurance Company of America in the red hot competition for consumer money decisions. In recent months, Metropolitan has agreed to buy the Century 21 Real Estate Corporation, the country's biggest real estate sales organization, and it has purchased the London-based Albany Life Assurance Company, giving Metropolitan its first major foothold in life insurance outside the United States and Canada since the 1930's. Mutual Funds Planned Furthermore, Met Life is laying plans to go after consumer investments by introducing a line of mutual funds next year through its State Street Management and Research Company subsidiary, and it is working out arrangements to offer its universal life policyholders the additional alternative of investing in real estate within a few years.

ALTHOUGH astronomers have long sought an explanation for the intricate and strikingly symmetrical cycles of sunspots, only now have they found a way to look into the solar interior and observe deep-seated motions that may be the controlling factors. The results, reported in recent weeks by a number of observers, have led to surprises and new puzzles regarding the manner in which various parts of the sun rotate and reverberate. The findings derive in large measure from a new form of analysis - helioseismology - applied to throbbing motions of the solar surface. The motions are caused by pressure waves resonating within the solar interior, like sound waves within a ringing bell. Much can be learned from them, just as one can estimate the size and other properties of a bell from its pitch.

FOR thousands of years, the Indus River has brought the blessing of water for crops and the curse of destructive floods. But today the Indus River poses a new danger to the site of an ancient civilization that flourished at the same time as those in the river valleys of the Tigris and Euphrates and the Nile. Moisture and salt deposits threaten to erode and destroy the remarkable Mohenjo Daro archeological excavation that has fascinated and awed scientists and visitors since its discovery under a giant mound of earth more than 60 years ago. ''Certainly the site is in danger,'' said M. A. Halim, director of the Pakistan National Museum in Karachi. ''It is threatened by subsoil water, salts in the water and salts in the air. There is also a danger from the river itself.''

The United Technologies Corporation said yesterday that Harry J. Gray, its forceful, flamboyant chairman who has been one of the nation's most aggressive acquirers of other companies, would relinquish his additional post as chief executive officer on Jan. 1. Succeeding Mr. Gray as chief executive will be Robert F. Daniell, the company's 51-year-old president and chief operating officer, United Technologies said. Analysts said the announcement, which had been anticipated for months on Wall Street, makes Mr. Daniell the apparent successor to Mr. Gray whenever he steps down as chairman of the diversified high-technology company. Without a Contract Mr. Gray, 65 years old, is working without a contract. A year ago, he was asked by the United Technologies board to remain chairman until the end of 1985, but he has not stated publicly when he plans to retire.

For the American consumer, the attempt to devalue the dollar could bring to an end an era in which foreign goods, from coffee to fine French wines, have been bountiful and inexpensive, economists said yesterday. At the same time, however, a weaker dollar could give renewed vigor to some key United States industries, including farming, agricultural machinery and construction equipment, that have all been battered by foreign competition. A weaker dollar could also improve the outlook for jobs in these industries, economists said. The decision Sunday by finance ministers from five major industrial nations to try to weaken the dollar has set off much analysis of who would most likely benefit and who would not if the dollar falls significantly. Although the strong dollar has been widely portrayed as a villain - in Congress, for example, legislators have been actively seeking ways to protect certain American industries - its actual impact has been more mixed. A weakened dollar, though it would be greeted with relief by some, would be missed by others.