For the past 30 years, Geotail has been sailing through the magnetic envelope that surrounds Earth to study this region of our atmosphere. But the long-running mission may be coming to an end as NASA and the Japan Aerospace Exploration Agency recently discovered that the spacecraft’s last remaining data recorder has failed.
The data recorder malfunctioned on June 28, leaving the spacecraft with no other means to collect science data as it journeys through the magnetosphere, NASA announced this week. Geotail was originally equipped with two data recorders, one of which stopped working in 2012 after gathering 20 years’ worth of data. The remaining recorder carried the mission through until recently when it experienced the malfunction.
Mission engineers at the Japan Aerospace Exploration Agency (JAXA) discovered the anomaly and have been working to figure out the cause and the amount of potential damage done. However, they have so far been unable to recover the spacecraft’s data recorder, which means that science data can no longer be collected or downlinked to ground control. NASA and JAXA are currently trying to determine how to best move forward with their joint mission.
Geotail launched on July 24, 1992, from Cape Canaveral Air Force Station in Florida. The primary goal of the mission was to study the elongated tail region of Earth’s magnetosphere, which is created by solar wind on the nightside of the planet. Earth’s magnetosphere is a giant magnetic field that surrounds our planet, protecting us from solar wind, radiation from the Sun, and cosmic rays from deep space. The magnetosphere is shaped by Earth’s north and south poles, as well as a steady stream of particles emitted by the Sun.
To observe the magnetosphere, Geotail was placed into an extremely elliptical orbit around Earth. The spacecraft performed 14 flybys of the Moon during its first two years to adjust its orbit, coming as close as 7,858 miles (12,647 kilometers) of the lunar surface. Geotail first observed the far region of the magnetotail, but the spacecraft’s lower orbit allowed it to get closer and study the substorms that took place near Earth, in addition to passing just inside the magnetosphere’s boundary plane on the dayside, according to NASA.
The mission was originally meant to last four years, but Geotail went far beyond its expected lifetime. During its 30 years in operation, the spacecraft has sent back valuable data on auroras, the type of material being emitted by the Sun, and the nature of Earth’s magnetic field. Geotail has certainly put in the work, but it may be time for this spacecraft to finally retire.