[AstroNet] Alien signal likely discovered within our lifetimes - Dr Seth Shostak

[Sam Rametse]

SPACE INNOVATION CONVENTION

16 July 2014

by Ben Deighton



http://horizon-magazine.eu/article/alien-signal-likely-discovered-within-our-lifetimes-dr-seth-shostak_en.html



*Alien signal likely discovered within ourlifetimes – Dr Seth Shostak*



Dr Seth Shostak, from the US-based SETI Institute, said the Square
Kilometre Array will help because it is faster and more

sensitive than current telescopes.



*What can Europe contribute to the search for alien civilisations?*



‘Europe is building the Square Kilometre Array. The Europeans are already
considering the fact that it ought to be outfitted with the right kind of
equipment to do searches, and they would be the most sensitive searches
ever.



*What difference would the Square Kilometre Array make to the search for
alien civilisations?*



‘To me this is a numbers game, you are looking for something that you think
is there, you’re looking for a needle in a haystack. So, instead of

going through the haystack with a teaspoon, if you can go through with a
shovel then success will happen a lot quicker.’



*Can you apply a numerical value to the chances of finding alien
civilisations?*



‘Yes you can, it depends on how many societies you think are out there
broadcasting signals that are going through our bodies as we stand here in
downtown Brussels. Nobody knows the answer to that. Carl Sagan (a NASA
astronomer who wrote the book on which the 1997 movie Contact was based)
thought a few million, Frank Drake (a pioneer of SETI) says maybe 10 000.
‘If any of those numbers are even approximately correct, then what that
implies is that, in order to succeed, you have to look at millions of star
systems, millions. So far in the entire history of the search for alien
civilisations we’ve looked carefully at only a few thousand, so that’s far
short of the mark. It’s very early days, but technology is speeding up the
search all the time. The Square

Kilometre Array would not only increase the search speed, it would increase
the sensitivity, so if there is a needle in that haystack, it will find it
more quickly.’



*How much will the increased speed and sensitivity of the Square Kilometre
Array influence our chances of finding an alien civilisation?*



‘Well it depends on how much time they spend doing it, but the Square
Kilometre Array obviously has a sensitivity that is 10 to 100 times better
than the kind of experiments that have been done before. It’s 10 times the
collecting area of Arecibo (a radio telescope located in Puerto Rico). It
has receivers that

allow it to look at a wide range of the radio dial all at once. The other
thing it’ll be able to do is maybe look at a big chunk of the sky at once
instead of one star at a time like we used to do at Arecibo. If they can
map a big chunk of the sky at once, obviously that’s a good thing, it’s
impossible to think of a way in which it’s not better.’



*In terms of the percentage improvement, what will it contribute?*



‘Well, it’s orders of magnitude, but SETI has been getting better. Compared
to what was done in 1960, it has been estimated that today’s experiments
are hundreds of trillion times more effective, whatever that number means.
But, of course there is this improvement all the time, and that’s why I
remain optimistic. If we were still doing the same experiment today that we
were doing 20 years ago, I might not be so optimistic.’



*Optimistic of what exactly?*



‘I’m optimistic that we will find a signal within the lifetime of the
people standing around here. I’m optimistic of that, I could be wrong.’



*The world’s most sensitive radio telescope*



Radio waves from space constantly bombard our planet, and cause the static
we can see and hear between TV channels and commercial radio stations. The
Square Kilometre Array will span two continents and be the world’s most
sensitive telescope listening to these radio waves. The Square Kilometre
Array, located in South Africa and Australia, will consist of three types
of sensors which when combined can cover a square kilometre of collecting
area,

hence its name. This will make it 50 times more sensitive and 10 000 times
faster than anything currently in use. Construction is scheduled to begin
in 2016, for initial observations by 2019, and the installation is expected
to be up and running by 2024. At the core of the initiative are 11 member
countries, while close to 100 organisations from around 20 countries have
participated in the design and development of the telescope. The EU has
spent over EUR 15 million on research projects preparing for the Square
Kilometre Array, and the initiative is backed by the European Strategy
Forum on Research Infrastructures.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.saasta.ac.za/pipermail/astronet/attachments/20140725/63451247/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 70449 bytes
Desc: not available
URL: <http://mail.saasta.ac.za/pipermail/astronet/attachments/20140725/63451247/attachment-0001.png>