A stricken Japanese Mars probe lost its last chance at success Tuesday, as the deadline for a remedy to its problems came and passed with no solution in sight. Nozomi continues to speed toward a close fly-by of the planet later this week.

An artist's concept of the Nozomi spacecraft. Credit: ISAS

Launched over five years ago in July 1998, engineers in charge of the 1,190-pound Nozomi probe have lost hope for a successful orbital mission around the Red Planet that was already almost half a decade behind schedule due to a laundry list of problems that plagued the beleaguered craft almost from the start.

Originally due for arrival at Mars in October 1999, Nozomi, which means "hope" in Japanese, approached Earth in December 1998 for a close fly-by that was supposed to guide the spacecraft onto a sling-shot course for Martian orbit insertion. A stuck valve caused an unexpected loss of propellant that left the probe crippled and unable to reach Mars under the normal mission plan.

A new trajectory was developed by ground controllers that featured an additional close Earth approaches that were successfully carried out last December and in June.

Compounding these issues was a violent solar flare in April 2002 that ravaged the craft's power system and faulty S-band communications equipment, among other complications.

The solar radiation knocked portions of the electrical system offline, and controllers tried throughout the summer and autumn months to recover full power production and to conduct the necessary maneuvers to set up for orbital insertion.

Had Nozomi succeeded in its goal to enter Martian orbit, the probe's scientific objectives included studying the planet's magnetic field and upper atmospheric properties as they interacted with the solar wind. The two small moons of Mars were also targets for investigation.

Nozomi will now fly past Mars at an altitude of roughly 1,000 kilometers and will continue on in solar orbit. Despite the failure of the mission, officials say they learned several important lessons that they will carry into future projects.

"Although we have had lots of difficulties to overcome, we have established a wide variety of engineering technologies for future planetary exploration," JAXA spokesman Junichi Moriuma told Spaceflight Now. "Also we have obtained very fruitful science results during the cruising phase."

Three landers and another orbiter all are winding up their journeys to the Red Planet over the next month. Europe's Mars Express orbiting platform and Beagle 2 lander were launched in June and are scheduled to arrive on Christmas Day.

NASA also is sending a pair of twin rovers that are due to land January 4 and January 25 to explore the Martian surface in greater detail than ever before.

Japan has suffered several setbacks in recent months, beginning in October with the loss of a $587 million Earth observation satellite, followed a month later by the failure of the indigenous H-2A rocket to deliver a set of spy satellites that were to keep tabs on North Korea.

These events have come shortly after Japan consolidated three aerospace and scientific organizations under one roof -- now called the Japanese Aerospace Exploration Agency, or JAXA.