Heart murmur. Heart murmurs are heart sounds produced when blood flows across one of the heart valves that are loud enough to be heard with a stethoscope. There are two types of murmurs. A functional murmur or physiologic murmur is a heart murmur that is primarily due to physiologic conditions outside the heart. Other types of murmurs are due to structural defects in the heart itself.
Voyager 2 passed Neptune in the summer of 1989, the first spacecraft to observe that planet. Passing about 3,000 miles above Neptune's north pole, Voyager 2 made its closest approach to any planet since it left Earth 12 years earlier.
They also discovered that its axis of rotation is almost zero. The first spacecraft to actually visit Venus was NASAâs Mariner 2, which flew past Venus in 1962. More recently, NASAâs Magellan spacecraft visited Venus and extensively mapped it surface with radar. ESAâs Venus Express arrived at Venus in May, 2006.hey also discovered that its axis of rotation is almost zero. The first spacecraft to actually visit Venus was NASAâs Mariner 2, which flew past Venus in 1962. More recently, NASAâs Magellan spacecraft visited Venus and extensively mapped it surface with radar. ESAâs Venus Express arrived at Venus in May, 2006.