Kepler's laws of planetary motion law" is what became the Second Law in the set of three; but Kepler did himself not privilege it in that way. Johannes Kepler published his first two laws about planetary motion in 1609, having found them by analyzing the astronomical observations of Tycho Brahe. Kepler's third law was published in 1619. Kepler had believed in the Copernican model of the solar system, which called for circular orbits, but he could not reconcile Brahe's highly precise observations with a circular fit to Mars' orbit—Mars coincidentally having the highest eccentricity of all planets except Mercury. His first law reflected this discovery.
Wide Field and Planetary Camera was intended for the panoramic observations of faint sources at the cost of angular resolution. The Planetary Camera had a 0.043 arcsecond pixel scale and was intended for high-resolution observations. Selection between the two cameras was done with a four-facetted pyramid that rotated by 45 degrees. As part of the corrective service mission (STS-61 in December 1993) the WFPC was swapped out for a replacement version. The Wide Field and Planetary Camera 2 improved on its predecessor and incorporated corrective optics needed to overcome the main mirror defect. To avoid potential confusion, the WFPC is now most commonly referred to