Fueless NASA Satellite Starts to Fall

A veteran of the sky is falling down, and for NASA experts, it's bittersweet. The Tropical Rainfall Measuring Mission (TRMM) satellite phoned home earlier this week to let the space agency know that it's running low on fuel, and with no way to get a fresh tank up to the orbiting spacecraft, NASA engineers are content to let it gradually fall to a fiery end.

Scott Braun, the TRMM's project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md., is impressed that the craft lasted as long as it did. As a joint project between NASA and the Japan Aerospace Exploration Agency (JAXA), the satellite was launched in 1997 to measure precipitation over the tropics. It made history as a pioneer craft for climate monitoring from space, boasting the Earth's first orbital precipitation radar.

"TRMM has met and exceeded its original goal of advancing our understanding of the distribution of tropical rainfall and its relation to the global water and energy cycles," he said in a recent statement.

According to Braun, the craft will now slowly descend into lower and lower orbits until it enters Earth's atmosphere, where it is expected to burn and fall to harmless pieces - a unexpected meteor shower some lucky stargazers might catch in two to three year's time.

The TRMM was initially intended to function for a three-year mission, but the craft has now spent 17 years circling the Earth. Occasional boosts of the craft's rockets are fired to keep it safe and within ideal orbit, but with little propellant left, the remainder will be used to simply keep the satellite from colliding with other orbiters as it gradually falls.

TRMM data, collected by JAXA and distributed by international efforts, has been instrumental in an effort to track global events, including tropical cyclones, floods landslides and drought - all important factors as experts continue to track our changing climate and its weather patterns.

Still, once TRMM slips from peak observational altitude, its data won't be missed. Its new-and-improved successor, the Global Precipitation Measurement (GPM) Core Observatory, was launched on Feb. 27, 2014.