NASA's Orbiting Carbon Observatory-2, or OCO-2, launched on July 2, 2014,
to begin the most precise measurements ever of carbon dioxide in Earth's atmosphere.
Lifting off atop a United Launch Alliance Delta II rocket from
Vandenberg Air Force Base in California,
the observatory was placed in a position with other Earth-focused spacecraft
so they could gather near-simultaneous data about different aspects
of the planet's climate.
The orbit of OCO-2 takes it roughly over both the north and south pole
on each pass.
That way, the spacecraft's instruments cover all of the Earth's surface,
a critical factor in determining the presence of carbon dioxide.
OCO-2's mission is slated to last two years,
although it could continue making observations for longer periods if needed.