"A mass anomaly sensor was a device used to detect and track an object based on the object's density. Personal-sized sensors were available. During the Idiran-Culture War, a starship-mounted sensor could detect an object with the density of a Culture Mind through over five kilometres of batholith. Anti-gravity could fool a passive sensor."@en . "Mass anomaly sensor"@en . "A mass anomaly sensor was a device used to detect and track an object based on the object's density. Personal-sized sensors were available. During the Idiran-Culture War, a starship-mounted sensor could detect an object with the density of a Culture Mind through over five kilometres of batholith. Anti-gravity could fool a passive sensor."@en . . .