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.
A large spacecraft carrying two probes and a lander would be sent out to investigate the ice planet orbiting in the far reaches of the Solar System some 2.8 billion miles from the Sun. Until now, the only spacecraft to visit Neptune was Voyager 2, which flew by the giant planet in 1989. Voyager 2, which has traveled to more planets than any other probe in history, probably still will be operating as the new probe arrives at Neptune.