A Spacecraft for All:
- Launched in 1978 and originally tasked with studying the outer reaches of the Earth’s magnetosphere, the International Sun/Earth Explorer 3 (ISEE-3) probe was given a second mission in the 1980s of chasing comets before being shut down in 1997.
- It was determined to be possible to reactivate the spacecraft in 2014, when it again made a close approach to Earth, and scientists discussed reusing the probe to observe more comets. However, NASA was no longer interested in recovering the spacecraft because of the limitations of its present budgets.
- A group of space enthusiasts began to talk. Retired and active aerospace engineers began to exchange ideas with avid HAM radio operators around the world. Finally, one group took charge. They made a agreement with NASA to have the rights to use ISEE-3 for the benefit of citizen science and obtained the old documentation.
- In May 2014, the ISEE-3 Reboot Project raised more than $150,000 with crowdfunding. Some original NASA engineers and various experts offered their help. The group gathered old equipment in their headquarters, an abandoned McDonald’s (they call it McMoons). After a lot of work and trial and error, two-way communication was achieved and ISEE-3 truly became ISEE-3 Reboot.
- The ultimate goal was to command the spacecraft to fire its rocket engines to change its trajectory and become captured by the Earth’s gravitational field. On July 2, the reboot project fired the thrusters for the first time since 1987. They spun up the spacecraft to its nominal roll rate, in preparation for the upcoming trajectory correction maneuver in mid-July. On July 8, a longer sequence of thrusters firings failed, apparently due to a loss of the nitrogen gas used to pressurize the fuel tanks
- On July 24, the ISEE-3 Reboot Team announced that all attempts to change orbit using the ISEE-3 propulsion system had failed. Instead, the team said, the ISEE-3 Interplanetary Citizen Science Mission would gather data as the spacecraft flies by the Moon on August 10 and enters a heliocentric orbit similar to Earth’s.
- Google Creative Labs documented the adventure and created the compendium which was delivered to the public domain last week, A Spacecraft for All.
I tried to summarize the main events of this great technical adventure. The details are interesting. I invite you to visit the google site and to read more:
my sources: gizmag (good article) and wikipedia
The ISEE-3 Reboot blog: spacecollege.org/isee3/