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.
Uranus, which was discovered by Sir William Herschel Prior to the invention of the telescope, the only known planets were Mercury, Venus, Earth, Mars, Jupiter, and Saturn. Uraâ¦nus was the first planet discovered by telescope. 48 people found this useful.