Computer Shopper - UK (2019-12)

ISSUE 382|COMPUTER SHOPPER|DECEMBER 2019 107

Drake equation, that’s the lifetime
of an intelligent communicating
civilisation. In his bookLight of the
Stars,heputs forward an explanation
to the Fermi Paradox. Although he
suggests that intelligent civilisations
almost certainly have existed in the
galaxy at one time,that’s not the same
as saying that theyexist now.Ita ll
depends on how long such civilisations
survive.Ift echnological civilisations
invariably annihilatethemselves in a
matter of acentury or two,due,say,to
runawayglobal warming,
we could currently be
the galaxy’s only
intelligent civilisation.
Given the continuing
lack of clarity over
the likelihoodof
extraterrestrial
intelligence,theoretical
studies have been
augmentedby the
practical approachof
trying to find evidence of
its existence.Needlessto
say, this is hugely taxing,
requiring huge radio
telescopes and plentyof
computing powerto
process the data streams.

THE SETITHE SETI
INSTITUTEINSTITUTE
The missionof the SETI Instituteisto
“explore,understand and explain the
origin and natureof lifeint he universe
and theevolutionof intelligence”.
As the name implies, oneof the
Institute’sprimary focuses is the
search forextraterrestrial intelligence,

aprogrammeof research it undertakes

using the AllenTelescope Array–a

multiple dish radiotelescope–to

listen forradio signals that have all

the hallmarksof originating from

an alien civilisation.

Given the numberof stars in the

galaxy –the veryfact that led manyto

believe that we can’t be alone–it’s

not hardto appreciatesomethingof

the challenge in searchingfor

extraterrestrial intelligence.Soh ow

does the SETI Instituteaddress the

questionof knowing whereto point

the array? Dr Seth Shostak, senior

astronomer and InstituteFellow,

explains the normal method isto adopt

abroad-brush approachto increase the

chancesof finding something.

“You would configure it inaway to

look at awide areaof the sk y, rather

than atiny little patchof the sk y,”he

observed, before acknowledging that

there are times when you might choose

to observeasmaller portionof the sky

to obtain stronger signals.

“Is it betterto look at five times as

many star systems, or is it betterto

look at asmaller numberof star

systems with five times more

sensitivity?” Shostak asks.

“That depends on your estimateof

what you think the aliens are doing.

Nobody knows whether we should

expect deliberately beamed

transmissions or just pick up their

SETI@HOME

Fancy getting in on the SETI actby processing radiotelescope data yourself?Well, headoff to

setiathome.berkeley.edu,d ownload the software that runs in the background whenever your PC

is idle ,and you might just makeaname foryourself as the person who discovered

extraterrestrial intelligence.

The SETI@Home project, managedby the Universityof California, Berkeley, uses data that’s

piggybacked from other observations made at the Arecibo radiotelescope in PuertoRico and

the Green Bank radiotelescope inWest Virginia. Data is split intosegments and automatically

farmed outto the current 100,000 users worldwide whose PCs, when combined,effectively

createadistributed supercomputer.

The number crunching is similarto that carried outby the SETI Institute, although the

SETI@Hometeam claim that they’re ableto search forsignals 10 timesfainter than any other

SETI initiative.

This doesn’t come withoutaprice,however .The coherent integration process that achieves

this is just another computationally intensive elementof SETI data processing.

⬆Despitemankind

being in spacefor

almost 60 years,

we’re still no closer

to answering that

age-old question,

‘Are we alone?’

Download the free SETI@Home

software and playyour part in looking

forextraterrestrial radio signals