The heliosphere is the area under the influence of the Sun; the two major components to determining its edge are the heliospheric magnetic field and the solar wind from the Sun. Three major sections from the beginning of the heliosphere to its edge are the termination shock, the heliosheath, and the heliopause. Five spacecraft have returned much of the data about its furthest reaches, including "Pioneer 10" (1972–1997; data to 67 AU), "Pioneer 11" (1973–1995;44 AU), "Voyager 1" and "Voyager 2" (launched 1977, ongoing), and "New Horizons" (launched 2006). A type of particle called an energetic neutral atom (ENA) has also been observed to have been produced from its edges.