Achieving communication with a spacecraft that has not used its engines in many years will be the goal of a group of volunteers, who will use the Arecibo radio telescope in Puerto Rico for this purpose.
The test is scheduled to take place this week, and the target is the 35-year-old ISEE-3 satellite (International Sun-Earth Explorer 3 - launched in 1978 and decommissioned in 1997). The aim is to return the spacecraft to a position from which it can resume examining the effects of solar weather on Earth's magnetosphere.
As reported in a related article in IEEE Spectrum, the satellite, which transmits two signals, came within “range” two months ago. Dennis Wingo, CEO of Skycorp Incorporated, and his colleagues believe that it still has enough fuel to return to its original position (Lagrange point L1, between the Sun and the Earth), but for this to happen, the command to activate its engines must be given by mid-June.
According to reports from the non-profit organization Space College, the “Away Team” is already in Arecibo and is preparing for “first contact,” which will use a 400-watt transmitter. One of the first goals is to send a command to enter engineering telemetry mode, to obtain more information about the status of the craft.
The main problem with ISEE-3 is that NASA no longer has the necessary equipment to communicate with the spacecraft, which is why in April Wingo and Keith Cowing, a former NASA employee and the editor of the sites NASAWatch and SpaceRef, launched a crowdfunding campaign on RocketHub to develop hardware and software to communicate with and control the satellite. The campaign met its goal, raising $125,000. The team has purchased special equipment from Ettus Research, which can be used to run programs that once had to be embedded in the hardware. The company helped with the programming part of the project, with one of its members flying to Arecibo.
If the spacecraft is in good condition, the next big challenge will be to estimate its trajectory, with the goal of firing the engines. The team will use transmitters and antennas at Arecibo, Morehead State University in Kentucky, the Bochum Observatory in Germany, and possibly the Allen Telescope Array in California for this purpose.
ISEE-3 is a "veteran" of Space, as after its launch in 1978 it had changed its purpose and name (International Cometary Explorer) in the early 1980s to "chase" Halley's Comet, and later took over the observation of the Sun again in 1991.
