WASHINGTON  Although NASA is concerned about last weekend’s rough, off-target landing of a Russian Soyuz spacecraft carrying three astronauts, an agency official expressed confidence on Tuesday that the Russians would solve the problem.

The Soyuz capsule, carrying a crew home from the International Space Station, made a steeper-than-normal re-entry early Saturday and landed in Kazakhstan about 260 miles short of its target.

Russian and American officials said the astronauts  Dr. Peggy A. Whitson of NASA; the Russian capsule commander, Col. Yuri I. Malenchenko; and a South Korean bioengineer, Yi So-yeon  had been exposed to twice the normal stresses of gravity, but were not harmed. They remain in Russia for normal postflight debriefings and examinations.

William Gerstenmaier, NASA’s associate administrator for space operations, told reporters Tuesday that the incident was “clearly a concern” to the agency but that it was too early to judge the impact on future space flights.