The probe, Japan's first interplanetary explorer, was set to end a five-year journey when it reached Mars next week. But officials at JAXA, Japan's space agency, said Nozomi was off target and that they would try to fire its engines late Tuesday to save the mission. It would be their final attempt because the probe was short on fuel.
JAXA spokesman Junichi Moriuma said the operation had failed, and that scientists had given up hope of salvaging the probe.
"Our mission to explore Mars is over," Moriuma told The Associated Press. "After today's attempt, almost all of the probe's fuel is gone."
Nozomi — which means "Hope" — was to circle Mars at an average altitude of about 550 miles in a two-year mission aimed at determining whether Mars has a magnetic field.
It was also set to examine the evolving Martian atmosphere's interaction with the solar wind — a stream of highly charged particles coming from the sun — and offer a close-up examination of the moons of Mars, Phobos and Deimos.
But malfunctions during Nozomi's journey altered its trajectory, putting the dragonfly-shaped, 1,190-pound probe into a course that was too low and raising concerns it might crash into — and possibly contaminate — the planet's surface. More than four years behind schedule, the probe was limping, nearly out of fuel, its electrical and communications equipment badly damaged by solar flares.
In sharp contrast with China's recent launch of its first manned rocket, Japan's space program, which has sent a probe into lunar orbit and now has another on its way to an asteroid, has suffered a string of setbacks.
Last month, an H-2A rocket carrying a pair of spy satellites strayed from its course and was destroyed just minutes after liftoff. Because the H-2A is the workhorse of Japan's space program, a review of the failure is expected to force the postponement of several other missions.
Despite Tuesday's failure, JAXA officials were able to lower the chances of Nozomi's collision with Mars, Moriuma said. The probability that the probe will hit the planet is now close to zero, down from about 1 percent before, he said.
Moriuma said scientists will also continue to modify Nozomi to carry out alternative missions, including monitoring solar activity, as it carves a wide path round the solar system. One lap is expected to take two years, he added.
Nozomi is part of an international fleet of Mars probes.
NASA's Mars Global Surveyor and Mars Odyssey are orbiting the planet and sending back images to Earth. Over the next month or so, the European Space Agency's Mars Express and three other spacecraft are expected to land on Mars.
By Kenji Hall