Radar Sparks SOHO’s Comeback After 1998 Silence
SOHO lost contact in 1998 during routine maintenance; a radar ping from the Arecibo Observatory confirmed its location and tumbling, triggering months of careful recovery to thaw frozen hydrazine, warm fuel pipes, and recharge the batteries. As sunlight on its panels improved, power returned and SOHO gradually came back online, with the episode prompting ground-procedure reforms. The mission has since become a highly productive solar observatory and prolific comet hunter, illustrating how a healthy spacecraft can be endangered by ground operations.