The smooth landing that ended a four-day flight for the shuttle Discovery this week is a badly needed success for NASA. It comes while desperate budget-cutters in Congress are looking everywhere for ways to slash expenses.

Nearly six months of delays and failures had caused a certain sense of cynicism about NASA's abilities and the value of the space program. Some potentially serious budget cuts loomed. The success of Discovery does not entirely resolve that threat, but it may have eased some of the pressure.During the orbital mission, the five-member shuttle crew launched the spacecraft Ulysses on a five-year flight to explore the poles of the sun. Ulysses appears to be functioning perfectly, a marked change from the problems that have plagued recent space projects. Maybe it's because Ulysses is a joint undertaking with the European Space Agency.

In one way, NASA has been victimized by both its successes and failures. Before the Challenger disaster, public interest dwindled away because shuttle flights had become relatively routine. In recent months, public disinterest and dissatisfaction grew because NASA could not routinely perform space projects. Either way, the agency had problems.

Maybe NASA doesn't work as well as it used to because some of the pride and zeal dissipated when the agency stopped its glamorous flights to the moon. The Providence Journal, for one, has suggested that building a space-age "trucking service" such as the shuttle may not be enough of an exciting mission to attract the best and brightest and most enthusiastic young talent into NASA's service.

That may not be the whole answer, but there is no denying that NASA needs a lift. Let's hope the flawless flight of Discovery opens the door to a new era of achievement and excitement - and opens the purse strings of Congress.