The International Sun-Earth Explorer-3 (ISEE-3) spacecraft was launched on 12 August 1978, into an orbit around the sun, and is now approaching Earth. NASA recently agreed to use this opportunity to pass control of the derelict spacecraft over to amateur enthusiasts. The ISEE-3 Reboot team has now made contact with the craft, and has established two-way communications.
The craft is sending information regarding its path and general condition. The group of around 20 amateur rocket controllers is planning to fire thrusters on board the spacecraft, which would bring the observatory near the Earth. When sent on its initial mission, the vehicle was orbiting the sun, in close proximity to our home world. The current approach is the closest the vehicle has come to the Earth in over 30 years.
"The ISEE-3 Reboot Project is pleased to announce that our team has established two-way communication with the ISEE-3 spacecraft and has begun commanding it to perform specific functions," mission managers wrote on the ISEE-3 Web site.
The vehicle was launched in the 1970's to study the solar wind, which constantly radiates from our parent star. There are 13 instruments on-board the observatory, and the new mission team is waiting to see if these are still operational. They intend to resume the observatory's orriginal function.
The ISEE-3 Reboot project plans to move the 35-year-old craft to a gravitationally stable point between the Earth and sun called Lagrangian 1 (L1).
Communication with ISEE-3 was established using the world's largest single radio telescope, located at Arecibo in Puerto Rico. The rate of information transfer is slow, even considering the age of the craft. The Reboot team is receiving and transmitting data at 512 bits per second.
"New data resulting from the project will be shared with the science community and the public, providing a unique tool for teaching students and the public about spacecraft operations and data gathering. The data also will provide valuable information about the effects of the space environment on the 36-year old spacecraft," NASA officials wrote in a press release announcing their agreement with the reboot team.
Data received from the spacecraft has also been verified by operators of other radio telescopes, including a station in Bochum, Germany and one at Morehead State in Kentucky.
Funding for the Reboot Project was collected on RocketHub, a crowdfunding Web site. The team has raised around $160,000 so far.
The team will not transmit for a few days, as they listen in, waiting for additional data from the disco-era vehicle.
