The immediate cause of sudden cardiac arrest is usually an abnormality in your heart rhythm (arrhythmia), the result of a problem with your heart's electrical system.
Version for printing. The first planet to be discovered was Uranus by William and Caroline Herschel on 13 March 1781. It was discovered by the fact that it showed a disk when viewed through even a fairly low powered telescope. The only other planets which have been discovered are Neptune and Pluto.
Suffice it to say that as a result of those calculations, Neptune was discovered on September 23, 1846 by the astronomer Johann Galle and his student Heinrich d'Arrest, after only thirty minutes of searching the sky, within a degree of the position predicted by Urbain Le Verrier.