The intrepid Voyager 2 spacecraft, nearly 3 billion miles from home and hurtling toward a close encounter with Neptune, changed course Friday in a maneuver equivalent to a right turn in interplanetary space.
"It made a slight veering to the right," Lanny Miller, manager of the Voyager flight engineering office at NASA's Jet Propulsion Laboratory, said of the critical move that aims the spacecraft toward Neptune's cloud tops.Voyager will cruise past the planet's north pole in a historic flyby next summer that will also permit some high-tech snapshots of Neptune's moon Triton.
Friday's maneuvering of Voyager from JPL's Deep Space Network will bring it 6,200 miles nearer the planet during its close encounter scheduled for 8 p.m. MDT Aug. 24, 1989.
Five hours after that flyby, Voyager will zoom within 24,000 miles of Triton for the first "close-up" view of that distant body, which some scientists say harbors lakes of liquid nitrogen.
"We really don't know anything about Triton. There's no way you can tell very much about it from Earth-based telescopes. We do know that it is about the size of Earth's moon.
"Some people believe it may have liquid nitrogen on it," Miller said. "But whether or not lakes of liquid nitrogen are there is purely speculative. That's why we're going - to find out."
Miller said the latest maneuvering of the craft, now 2.6 billion miles from Earth, involved "a change in velocity of 1 mph," which slightly slowed its usual traveling speed of 42,466 mph.
"We were headed some distance away and now we've moved it a little bit closer to the planet," said Miller, who noted Voyager is "only 257.7 million miles" from its destination.
While en route, the spacecraft is sending back "information about the solar system medium and what we call field and particle data," Miller said of reports on the highly charged space through which the probe is traveling.