Voyager
2
Feb
13 2021
We
are realists,
or
so we imagine ourselves.
Seeing
is believing
we
stubbornly maintain.
So
we scoff
at
the psychics and mediums
soothsayers
and oracles
astrologers
and seers.
Yet
what child doesn't talk
to
her beloved plush toy,
even
threadbare and eyeless
its
stuffing emptied out?
Who
names their car,
and
when it refuses to start
threatens
and cajoles?
Who
doesn't rant
at
the ghost in the machine
when
the damned computer balks?
And
who would agree
to
wear a sweater Hitler wore,
unafraid
of
the power of transference?
We
naturally invest
dumb
objects with life,
as
if all matter disguised
some
sentient heart.
So
after 44 years in space,
hurtling
away
from
the jewel-like planet
it
once called home,
I
can't help but project humanity
on
that nifty little satellite
as
it journeys ever outward.
At
12 billion miles, and counting,
35
hours
at
light-speed 2 ways.
It's
pluck and resilience
in
braving the unknown.
Its
dogged solitude
so
long alone.
And
its sturdy competence,
faithfully
signalling
like
a loyal emissary
of
the land-locked human race.
Old
technology
built
to last.
Like
the little engine that could
puffing
gamely uphill
chanting
“I think I can, I think I can,”
it
dauntlessly heads out
into
the cold and dark
of
our vast uncharted galaxy
and
continues to astound.
Where
the sun is a star
lost
in the cosmos,
and
earth extinguished
in
the blackness of space.
I
sometimes feel the same,
so
far from the light
and
the heat of human contact,
where
even gravity is absent
and
there's no turning back.
But
still sending out my signal
as
Sputnik once did,
a
faint insistent beep
as
it circled close to earth.
But
instead of marvelled at and feared
forgotten
and unheard.
Every
time I've read about this remarkable spacecraft, I've found myself
personifying it like this. I read this article in the Globe today,
and the possibility of a poem immediately leapt to mind. This time, I
actually sat down to write it!
Of
course, a lot of people (most?) are fabulists, not realists; and
instead of scoffing at these charlatans, credulously believe them.
I'm
not so skeptical, though, of those who distrust their eyes. Because
seeing isn't believing. Our eyes aren't objectively recording
the world. What we perceive depends upon selective vision: what
attracts our attention, what we fail to notice. And what we perceive
depends upon how the brain processes the images coming into it:
filtering and colouring them by context, expectation, memory, and our
own prejudices and habit of mind.
After
a year of silence, NASA restores communications with Voyager 2
Last March, the agency dismantled an antenna
in Australia – the only way to send messages to the spacecraft –
for upgrades
In the nearly 44 years since NASA launched
Voyager 2, the spacecraft has gone beyond the frontiers of human
exploration by visiting Uranus, Neptune and, eventually, interstellar
space. In March, the agency was compelled to shut down its only means
of reaching 12 billion miles across the heavens to this robotic
trailblazer. On Friday, Earth’s haunting silence came to an end as
NASA switched that communications channel back on, restoring
humanity’s ability to say hello to its distant explorer.
Because of the direction in which it is flying
out of the solar system, Voyager 2 can only receive commands from
Earth via one antenna in the entire world. It is called DSS 43 and it
is in Canberra. It is part of the Deep Space Network, or DSN, which
along with stations in California and Spain, is how NASA and allied
space agencies stay in touch with the armada of robotic spacecraft
exploring everything from the sun’s corona to the regions of the
Kuiper belt beyond the orbit of Pluto. (Voyager 2’s twin, Voyager
1, is able to communicate with the other two stations.)
A round-trip communication with Voyager 2 takes
about 35 hours – 17 hours and 35 minutes each way.
DSS 43 is a 70-metre dish that has been
operating since 1973. It was long overdue for upgrades, especially
with new robotic missions headed to Mars this year and even more
preparing to launch to study other worlds in the months and years to
come. So last year, the dish was switched off and dismantled, even
though the shutdown posed considerable risk to the geriatric Voyager
2 probe.
Like everything in 2020, what would have been a
normal antenna upgrade was anything but. Usually, the mission’s
managers at NASA’s Jet Propulsion Laboratory in California would
send about 30 experts to oversee the dish’s makeover. But
restrictions imposed during the COVID-19 pandemic reduced the team to
four.
At the Canberra station, the crew working on
the upgrade had to be separated into three smaller teams, said Glen
Nagle, outreach manager at the Canberra Deep Space Communication
Complex.
“So
there was always a backup team in case anybody got sick, and you
could put that team in isolation, and the other team could come in
and cover for them,” he said.
They also split the teams into morning and
evening shifts to ensure physical distancing.
While Voyager 2 was able to call home on the
Canberra site’s smaller dishes during the shutdown, none of them
could send commands to the probe. If anything had gone wrong aboard
the probe during the last year, NASA would have been powerless to fix
it.
Although NASA has been unable to send full
commands to Voyager 2, it did send one test message to the spacecraft
at the end of October when the antenna was mostly reassembled. A
device on board called the command loss timer, something like a dead
man’s switch, is used to help the spacecraft determine whether it
has lost contact with Earth and should protect itself by going into a
form of electronic slumber.
The October test reset the timer and
successfully told the spacecraft to continue operating.
“I
think there was probably a big sigh of relief there,” Mr. Nagle
said. “And we were very pleased to be able to confirm that the
spacecraft was still talking to us.”
The work got high marks from NASA officials in
the United States.
“The
DSN folks in Canberra did a remarkable job under the pandemic
conditions just to upgrade DSS 43,” said Suzanne Dodd, the Voyager
mission project manager and director of the Interplanetary Network
Directorate at the Jet Propulsion Laboratory.
“I’ve
got 100-per-cent confidence in that antenna, that it will operate
just fine for a few more decades. Long past when the Voyagers are
done.”
Both Voyager 1 and Voyager 2 hold the records
for the farthest a spacecraft has ever travelled and for the longest
operating mission. Voyager 2 has had a few hiccups over the years,
but it is still feeling its way around in the dark, making
discoveries about the boundaries that separate our solar system from
the rest of the Milky Way galaxy.
“I’ve
seen scientists whose backgrounds are in astrophysics now looking at
Voyager data and trying to match that up with data they have from
ground-based telescopes or other space-based telescopes,” Ms. Dodd
said.
“That’s
kind of exciting to go from a planetary mission to the heliophysics
mission and now, practically into an astrophysics mission.”
While Voyager 2 keeps chugging along, Ms. Dodd
and her colleagues are preparing to switch off one of its scientific
sensors, the Low Energy Charged Particle instrument. Doing so will
ensure that the spacecraft’s limited power supply can keep its
other systems, particularly its communications antenna, warm enough
to function.
While that will reduce the spacecraft’s
scientific output, the main goal now is longevity.
“The
challenge is not in the new technology, or the great discoveries,”
Ms. Dodd said. “The challenge is in keeping it operating as long as
possible and returning the science data as long as possible.”
The team estimates that both spacecraft can
operate for another four to eight years, and NASA last year granted
the team three more years of flying time.
“The
spacecraft continues to plug along,” Ms. Dodd said. “It always
surprises me.”
