Astronomy - USA (2020-01)

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role in the 2000 movie The Dish, which
tells the story of the Parkes telescope’s
role in tracking the Apollo 11 mission a
half-century ago.
The actual antenna, the giant 210-foot
(64 m) “dish,” is visible from miles away.
Built in 1961, it was at the time the larg-
est fully steerable radio telescope in the
Southern Hemisphere — and today is
superseded only by the 70-meter dish at
Tidbinbilla (which awaited us at our next
stop). Thanks to a series of upgrades over
the years, the telescope is now some
10,000 times more sensitive than it was
back in the ’60s, and it continues its
groundbreaking science.
The inner part of the dish is solid
metal, while the outer section is com-
posed of a fine metal mesh, resulting in


the unique two-tone appearance. The
many supporting struts, however, mean
there are a lot of places for birds to build
their nests, as Jane Kaczmarek, a staff
scientist at Parkes, explained to us.
“There are a lot of very angry gallahs
up there,” she said, referring to the ubiq-
uitous pink-colored cockatoo. “When
you tip the dish down to the horizon,
they get upset.”
The whole shebang — weighing 1,000
metric tons — rests delicately atop the
elegant circular brickwork of the central
building, which is dubbed “the tower”
even though it’s dwarfed by the gigantic
dish above it.
Parkes is responsible for a string of
important astronomical discoveries. It
was the first telescope to detect the

Magellanic Stream, a wispy trail of gas
extending through the Magellanic
Clouds and stretching across half the sky.
Astronomers think the stream formed as
a result of our own galaxy’s gravitational
tug on the Magellanic Clouds over hun-
dreds of millions of years. In 2007, the
telescope made the first detection of a
fast radio burst (FRB), a mysterious burst
of energy from deep space. More than 30
FRBs have since been recorded, most of
them by the Parkes dish.
The telescope also takes part in the
search for extraterrestrial civilizations as
part of the Breakthrough Listen project.
And the dish continues to track NASA
spacecraft, including Voyager 2. In fact,
it was “listening” to Voyager 2 at the time
of our visit. It was a thrill to see the little

ABOVE: The many domes of Siding Spring Observatory blossom across the
summit of Mount Woorut, near Coonabarabran. The square “dome” at right
houses the Australia National University’s 2.3-meter telescope, also known
as the Advanced Technology Telescope.


RIGHT: The author stands in front of the 3.9-meter Anglo-Australian Telescope
at Siding Spring Observatory, the largest optical telescope in the country.


The dome at left houses the 49-inch
(1.24 m) U.K. Schmidt Telescope at
Siding Spring Observatory.
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