Lou Dobbs, president of CNN Financial News and the first anchor of a nightly business report on television, resigned yesterday to launch a new Internet venture dealing with outer space.

The anchor of "Moneyline," which began with the creation of CNN in 1980, has clashed repeatedly with CNN executives in Atlanta, particularly CNN/USA President Rick Kaplan, and the hostilities recently spilled into public view. Shortly after Dobbs cut away from a speech by President Clinton in Littleton, Colo., to resume "Moneyline," he noted tersely on the air that "CNN President Rick Kaplan wants us to return to Littleton."

"There was an ongoing series of frustrations in dealing with Atlanta," said one CNN insider. "There wasn't any big explosion. This has been building for a while."

But financial incentives may have played a larger role. Dobbs, said by a colleague to have caught "Internet fever," will become chairman of Space.com, a Web site that takes off July 20 (the anniversary of the 1969 landing on the moon) and in which he will have a substantial equity stake.

Dobbs said in an interview that it became impossible for him to stay at CNN once he "moved from a passive investor in Space.com to wanting to do something more, to be active in its creation. I truly believe space is the biggest story of this century and the next, and I really wanted to be part of it."

Andy Serwer, Fortune's editor-at-large, said that Dobbs "personified CNNfn and business news. He's a giant of the field. Before there was CNBC, there was Lou Dobbs."

Dobbs has privately maintained that he is not quitting because of the difficulties with other CNN executives, and he said last night that the decision comes with "some pain for all the blood and sweat I put into this place."

The soon-to-be-launched venture, backed by Venrock Associates, a major investment firm founded by the Rockefeller family, will feature space news, space fiction, live feeds, science and business content, and educational material for children. Dobbs said he hopes to take the company public, which could bring him many millions of dollars if the market for Internet stock offerings stays hot.

Dobbs, 53, a close friend of CNN founder Ted Turner, was the driving force behind the creation of three-year-old CNNfn, which reaches just 11 million homes and lags well behind industry leader CNBC, which reaches about 75 million. But "Moneyline," which is carried on the main CNN network and recently expanded to an hour of general and business news, remains an important force on Wall Street.

Interim "Moneyline" anchors will include Willow Bay, who hosts the CNN magazine programs produced with Fortune and Entertainment Weekly. In a statement, CNN News Group Chairman Tom Johnson praised Dobbs for his "immeasurable" contributions over two decades."

His resignation was so closely held that even his top deputies did not know he was quitting. Dobbs, who did not host "Moneyline" last night, was in last-minute negotiations over the terms of his departure, and said he is contractually barred from competing on other networks.

Dobbs was a strong-willed and controversial force within the network, and his departure gives the Atlanta headquarters an opportunity to maintain tighter control over its financial spinoff. Rather than name a new president, the network said the two next-highest CNNfn officials would run the operation and report to Johnson.

Jeff Gralnick, executive vice president for "Moneyline" and other financial programming, will continue in that role, as will CNNfn's executive vice president, David Bohrman. Gralnick joined CNN this year from ABC, where he was a producer and executive for 23 years, and is a former executive producer of "NBC Nightly News." Bohrman was hired last year after a long career at ABC and NBC, where he oversaw special events.

Dobbs has threatened to leave CNNfn before, once after starting negotiations with CNBC. In 1997, he came close to quitting but then the network bowed to his demand to expand CNNfn from 14 to 18 hours a day and commit to eventual 24-hour coverage. But CNN was soon taken over by Time Warner, and Dobbs has been at odds with other corporate officials over his efforts to keep CNNfn.com independent of the larger Time Warner Web site.

But CNN was soon taken over by Time Warner and Dobbs has been at odds with other officials over the independence of the CNNfn.com Web site. Dave Kansas, editor of TheStreet.com, a popular financial news service, said of Dobbs: "CNNfn itself struggled, but he managed to put it on the Web and do a great job of building traffic. . . . Lou Dobbs had a reputation for being a little bit gruff that helped a lot in the past but may have hurt him this time."

Howard Kurtz appears on CNN's weekly media program.

CAPTION: Lou Dobbs