Voyager 2 Reached 4 Planets in 12 Years via Rare 175-Year Gravity Assist
Updated
Updated · Daily Kos · Jul 15
Voyager 2 Reached 4 Planets in 12 Years via Rare 175-Year Gravity Assist
3 articles · Updated · Daily Kos · Jul 15
Summary
Voyager 2 used repeated gravitational assists to fly past Jupiter, Saturn, Uranus and Neptune in a 12-year Grand Tour spanning about 4.5 billion kilometers.
The slingshot method works by stealing a tiny share of a planet’s orbital energy: a probe passes behind the planet, changes direction and leaves the encounter faster relative to the Sun.
A rare alignment of the four giant planets made the mission possible in 1977, a launch opportunity that comes only about once every 175 years.
Launched on Aug. 20, 1977, Voyager 2 reached Jupiter in 1979, Saturn in 1981, Uranus in 1986 and Neptune in 1989; the same journey without assists would have taken nearly 30 years.
The report says plotting such routes requires extensive simulation of multi-body dynamics rather than a simple formula, with the next comparable Grand Tour window around 2150.