  Quark nuggets are theoretical objects composed of approximately equal numbers
of up, down, and strange quarks. They are also called strangelets, nuclearites,
AQNs, slets, Macros, and MQNs. Quark nuggets are a candidate for dark matter,
which has been a mystery for decades despite constituting ${\sim}85\%$ of
matter. Most previous models of quark nuggets have assumed no intrinsic
magnetic field; however, Tatsumi found that quark nuggets may exist in
magnetars as a ferromagnetic liquid with a magnetic field between $10^{ 11}$ T
and $10^{ 13}$ T. We apply that result to quark nuggets, a dark-matter
candidate consistent with the Standard Model, and report results of analytic
calculations and simulations that show they spin up and emit electromagnetic
radiation at ${\sim}10^{ 4}$ Hz to ${\sim}10^{ 9}$ Hz after passage through
planetary environments. The results depend strongly on the value of $B_{o}$,
which is a parameter to guide and interpret observations. A proposed sensor
system with three satellites at 51,000 km altitude illustrates the feasibility
of using radio-frequency emissions to detect 0.003 to 1600 MQNs, depending on
Bo, during a five year mission.
