http://www.skyandtelescope.com.au 23hiscareerasaTO:firstonMauitoworkforNASA’s
Lunar Laser Ranging Experiment, and later on the Big
Island with the United Kingdom Infrared Telescope
andKeckObservatory.Inthe1990s,Aycockhelped
astronomers collect the first science data from the
newKeckItelescope,andhealsoparticipatedinthe
constructionandcommissioningofKeckII.Hehas
nowworkedasaTOonMaunaKeaforover30years.
“OnceIfoundaplacewiththeHawai‘iastronomical
observatories,Iwashooked,”hesays.“Therewasno
turning back.”Call the operator
One night while holed up in the control room during
an observing session at Gemini North, Ball heard
athunderousbang!from the dome floor overhead.
Thelightsflickered.Hehustledupthethreeflights
of stairs into the dome — where the temperature
was approximately −10°C — and encountered a mini
catastrophe: the5-cm-thick, solid piece of steel that
transmittedpowertothedomehadsnappedinhalf.
Gemini’s massive dome moves azimuthally on a
track containing high-voltage power lines, which
supply the power to all the vent gates, dome, shutter
and lights. The connection to one of those lines
had failed, creating a massive arc of electricity that
snapped the steel.
“I was frantically trying to dismantle the assembly
sowecouldgetthedomeclosed,”saysBall.Whilehe
wasworking,thefogrolledinandalightdustingof
snowandicestartedtofallonthedomefloor.“I’m
standing there in the dark and fog with a flashlight,
frozen-stiff fingers, numb face, and manoeuvring my
way around damaged pieces of this dome track, all the
while working against the clock!”
Luckily, Ball was able to close the mirror cover
to preserve the optics during the bad weather. After
engineers guided him by phone in re-arming the powerbreaker and resetting the telescope’s interlocks, he
restoredpowertothedomesohecouldproperlyclose
downthetelescope.“Thedaycrewwasabletocheck
thesystemthenextday,”hesays,“sowewerebackto
normaloperatingconditionsassoonaswere-opened
thenextnight.”
Such incidents are thankfully rare. Some
observing sessions are relatively easy, such as when
there are only a few, long-exposure targets. But TOs
are the first line of defense when something goes
wrong at a telescope.
“Wealwaysmustbeawareandonthealertforany
small problem that might stop operations altogether,”
Aycocksays.“Noliveswillbelost,butanastronomer’s
life career could be jeopardised.”
In2009,BallhelpedastronomersobserveNASA’s
Lunar Crater Observation and Sensing Satellite
(LCROSS) smash into the Moon. The impact, in
which LCROSS and its Centaur rocket intentionally
crashed into Cabeus Crater at the Moon’s south pole,
was designed to eject material that astronomers
couldstudyspectroscopicallyforsignsofwaterand
hydrocarbons.
Preparing for the crash took lots of planning. The
TOs coordinated with astronomers and engineers
tofigureoutwheretopointthetelescopeandwhich
filters to use so that observers caught the expected flash
withoutsaturatingthedetector.“Thefactthatitwas
onlygoingtohappenonceandwedidn’tgetanysecond
chancesreallymadeitexcitingandchallenging—and
we pulled it off !”
Sometimes, TOs have to make choices about whether
to proceed with observing or not — regardless of how
unpopular it will make them with the astronomers.
But holding out can have its rewards, too. One night
at Gemini North, Ball and some astronomers were
observing in extremely windy conditions, probably 20
metres per second (72 kph). All telescopes have differentNIGHT
CLASSES
Left: One of
the 8.2-metre
telescopes of the
four-scope Very
Large Telescope
at Paranal, Chile.
Right: Telescope
instrument
operator Claudia
Cid (left) gives
data-handling
administrator
Cecilia Cerón a
crash course on
how operators
prepare for
the night’s
observations,
while sitting in
the Very Large
Telescope’s
control room.
Cerón and her
colleagues
oversee the
observatory’s data
flow, beginning
when the
instrument takes
an image in Chile
and ending when
it’s delivered
to ESO staff in
Germany.ESO / G. HÜDEPOHL
(ATACAMAPHOTO.COM)
ESO/MAXALEXANDER