NASA felt it had gotten its money's worth out of the International Sun-Earth Explorer-3 mission back in the 1980s. Its last scientific mission ended in 1997, and contact was suspended in 1998. But time and a fortuitous orbit mean that ISEE-3 is now catching up with Earth and will make a close pass this summer. When we first noted this story last year, some enthusiasts were suggesting that the probe should be revived and returned to scientific duty, but the perpetually tight budgets at NASA made that outcome unlikely.

Yesterday, NASA announced that it found a solution: it would hand the keys to the probe over to those enthusiasts.

Launched in 1978, the hardware was initially sent to the L1 Lagrange point between the Earth and Sun and was used to study the solar wind. With that mission complete, the International Sun-Earth Explorer-3 was renamed the International Cometary Explorer and was sent into orbit around the Sun, where it passed through the tails of two comets before its mission ended in 1997.

ISEE-3 is now catching up with Earth again. At last check, all its instruments were functional, which raises the possibility that it could be restored to its former location at the L1 Lagrange and returned to scientific duty. That restoration is more challenging than it might sound, as NASA hasn't maintained the hardware and communication protocols necessary to communicate with ISEE-3.

The challenge didn't deter a number of enthusiasts at the ISEE-3 Reboot project, which had been attempting to restore contact with the spacecraft without official permission. That situation changed yesterday with the announcement of an agreement between NASA and Skycorp, Inc., a company that's backing the Reboot project. The "Non-Reimbursable Space Act Agreement" gives the rebooters permission to try to control the spacecraft, and it specifies the conditions that need to be met before attempts are made to do so.

Should the attempt be successful, any new data that results will be placed in the public domain. Right now, the group has a team at the Arecibo Observatory attempting to reestablish contact.