NASA has re-established complete communication with Voyager 2 by sending a
"interstellar shout" that corrected the distant probe's antenna alignment,
the space agency announced Friday.
Launched in 1977 to investigate the outer planets and serve as a beacon of
mankind to the rest of the cosmos, it is now more than 12.3 billion miles
(19.9 billion kilometers) away from Earth, well outside the solar
system.
On July 21, a sequence of programmed orders delivered to the spaceship
forced the antenna to point two degrees away from Earth, jeopardizing the
spaceship's capacity to broadcast and receive signals and jeopardizing its
mission.
It was not believed that the problem would be rectified until at least
October 15, when Voyager 2 was due to perform an automatic realignment
operation.
Engineers recruited the support of the Deep Space Network (DSN) on Tuesday
to discover a carrier or "heartbeat" wave from Voyager 2, however the signal
was still too feeble to decode the data it carried.
NASA's Jet Propulsion Laboratory (JPL), which created and manages the
probe, announced in a fresh report on Friday that it had succeeded in a
long-shot effort to send instructions that righted the vehicle.
"The Deep Space Network used the highest-power transmitter to send the
command (the 100-kw S-band uplink from the Canberra site) and timed it to be
sent during the best conditions during the antenna tracking pass in order to
maximize possible receipt of the command by the spacecraft," said Voyager
project manager Suzanne Dodd.
This "interstellar shout" took 18.5 hours to reach Voyager at light speed,
and it took 37 hours for mission controllers to determine if the command
worked, according to JPL.
The probe began providing science and telemetry data on August 4 at 12:29
a.m. Eastern Time, "indicating that it is operating normally and that it
remains on its expected trajectory," according to JPL.
In December 2018, humanity's beacon Voyager 2 exited the Sun's protective
magnetic bubble, known as the heliosphere, and is now sailing into space
between the stars.
It studied Jupiter and Saturn before departing our solar system, and it was
the first and so far only spacecraft to visit Uranus and Neptune.
Voyager 2's twin, Voyager 1, was the first spacecraft to reach the
interstellar medium in 2012, and is now about 15 billion miles away from
Earth.
Both have "Golden Records"—12-inch gold-plated copper disks meant to tell
extraterrestrials about our Earth.
A map of our solar system, a chunk of uranium that functions as a
radioactive clock, allowing receivers to date the spaceship's launch, and
symbols indicating how to play the record are among the items.
The disks' contents, chosen for NASA by a team led by famed astronomer Carl
Sagan, include encoded pictures of Earth's life as well as music and sounds
that may be played with the attached stylus.
For the time being, the Voyagers continue to send scientific data, albeit
their battery banks are scheduled to run out sometime around 2025.
They will then continue to explore the Milky Way in quiet, maybe for
eternity.
