Superconductivity and carbon nanotubes, are Type I, while almost all impure and compound superconductors are Type II. Conversely, a spinning superconductor generates a magnetic field, precisely aligned with the spin axis. The effect, the London moment, was put to good use in Gravity Probe B. This experiment measured the magnetic fields of four superconducting gyroscopes to determine their spin axes. This was critical to the experiment since it is one of the few ways to accurately determine the spin axis of an otherwise featureless sphere. Superconductivity was discovered on April 8, 1911 by Heike Kamerlingh Onnes, who was studying the resistance
1732 Heike November 1977 (). 1732 Heike 1732 Heike, provisional designation , is a stony Eoan asteroid from the outer region of the asteroid belt, approximately 24 kilometers in diameter. It was discovered on 9 March 1943, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany, and named after Heike Neckel, the granddaughter of astronomer Alfred Bohrmann. The S-type asteroid is a member of the Eos family. It orbits the Sun in the outer main-belt at a distance of 2.7–3.3 AU once every 5 years and 3 months (1,911 days). Its orbit has an eccentricity of 0.11 and an inclination