Termination of Operation of Tropical Rainfall Measuring Mission (TRMM)

The Tropical Rainfall measuring Mission (TRMM) satellite, launched on
28 November 1997 by H-II launch vehicle No.6 to an altitude of about
350km, has been operated beyond the completion of the nominal mission
operation phase in the end of January 2001. Today, the Japan Aerospace
Exploration Agency (JAXA) has decided to agree to the proposal from
National Aeronautics and Space Administration (NASA) to terminate the
operation of TRMM.

TRMM is the joint project of Japan and U.S. Japan is responsible for
developing one of the onboard observation instruments, the
Precipitation Radar (PR), and launching the satellite by H-II launch
vehicle. Since the launch, the observation has been continued for more
than 6 years, exceeding the initially planned nominal observation
period of 3 years. TRMM has succeeded to collect huge valuable
observation data, including meteorological phenomenon over land and
sea, and the global hydrological cycle.

In last October, NASA, who is responsible for TRMM operation, proposed
to terminate TRMM operation and to perform safe ocean disposal of the
satellite through controlled re-entry as soon as possible. This
proposal was due to the safety concern about the continuation of the
operation of the satellite which has far exceeded its design life.
JAXA asked NASA to study the possibility of continuing TRMM
observation within the safety limitation, and has worked with NASA to
find a solution of continuing the operation. However, today, JAXA has
reached to the conclusion to agree to NASA’s proposal.

It is expected that TRMM will terminate its observation operation
during July, followed by the altitude lowering drift down phase.
Controlled re-entry and safe ocean disposal will be completed about a
year later.

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http://www.jaxa.jp/press/2004/07/20040709_trmm_e.html