Researchers showed that nearby dielectric materials can drain energy from ultracoherent nanomechanical resonators without physical contact. Static charges on or in these tiny devices trigger non-contact friction, especially limiting low-frequency modes used in precision sensing and quantum technologies. Static charges make the world’s most sensitive nanoresonators lose energy to nearby materials, revealing a hidden design limit for next-generation quantum and sensing devices. Non-contact friction in ultracoherent nanomechanical resonators near diele... [8477 chars]