When the first pulsar was discovered at Cambridge in the 1960s,
astronomers struggled to find an explanation for the metronome-like
regularity of the pulses. For a short time the source was dubbed
"LGM" for Little Green Men, as the precise 1.34-second periodicity of the pulses
seemed more like a artificial beacon than any natural astrophysical phenomenon.
The discovery of other pulsars,
with other periods, in other parts of the sky, quickly convinced scientists
that these were not extraterrestrial signals, with the realisation
that pulsars were in fact rapidly rotating neutron stars.
So what to make of the Little Green Telescopes above?
Are these for transmitting signals to Little Green Men? No, these
are elements of the ASKAP array,
lit up at night for the filming of the White Spark production
Beyond the Milky Way.
ASKAP
has successfully discovered a pulsar, as a highly polarised, steep spectrum
radio source, which was subsequently confirmed by timing observations at Parkes to
have a period of 2.77 milliseconds.
And ASKAP's wide field of view and good sensitivity means it is well-placed
to contribute to on-going searches for extraterrestrial intelligence.
(Image credit: Chris Brayton)
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