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.
Nearly 4.5 billion kilometers (3 billion miles) from the Sun, Neptune orbits the Sun once in 165 years, and therefore has made not quite a full circle around the Sun since it was discovered. With an equatorial diameter of 49,528 kilometers (30,775 miles), Neptune is the smallest of our solar system's gas giants.n the summer of 1989, NASA's Voyager 2 became the first spacecraft to observe the planet Neptune, its final planetary target. Passing about 4,950 kilometers (3,000 miles) above Neptune's north pole, Voyager 2 made its closest approach to any planet since leaving Earth 12 years earlier.