Page 8 - Astronomy - October 2017 USA

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EVERYTHING YOU NEED TO KNOW ABOUT THE UNIVERSE THIS MONTH . . .

HOT BYTES >> IN REVIEW TEAMWORK BLACK HOLE
ANALOG
The European Space
NASA has established an
independent committee to Agency announced its Researchers at the
TRENDING review costs and scheduling intention to develop LISA, University of Nottingham
TO THE TOP associated with the flagship the Laser Interferometer used a water bath to
Wide Field Infrared Survey Space Antenna, in col- simulate the space
Telescope (WFIRST). laboration with NASA. around a black hole.
SNAPSHOT Voyager 2 captured
this image of Saturn
Reflections (left) on its approach
on August 4, 1981,
from a distance of
on Voyager 13 million miles
(21 million
kilometers). Aside
from the planet’s
We’ve come a long way since, but the colorful cloud tops
and rings, the image
Voyagers’ Grand Tour set the stage. shows (in order of
distance from the
planet) the moons
Tethys (closest),
In 1977, when the twin Voyager space-
Dione, and Rhea, as
craft launched, our knowledge of the well as the shadow
solar system was pretty primitive. Twelve of Mimas. Some
23 years later, the
years later, after Voyager 2’s exploration of
Cassini spacecraft
Neptune, the first stage in understanding captured Saturn
our family of planets — the “Grand Tour” (bottom) in one
— was over. Now the Voyagers are more of its greatest
composite shots.
than 100 times the Earth-Sun distance
away, silently moving still farther out, and
still providing data about the outer part of
the solar system.
The Voyagers’ Grand Tour gave us the
first detailed exploration of Jupiter and
Saturn, although those missions were fly-
bys, and the initial close-up looks at Uranus
and Neptune. We only explored Pluto for
the first time, of course, many years later
with the New Horizons spacecraft. NASA/JPL AND NASA/JPL/SPACE SCIENCE INSTITUTE; TOP FROM LEFT: NASA; NASA;
For those who weren’t around in the
1970s and ’80s, it’s hard to understand the
Voyagers’ thunderous impact. Previous
explorations of Jupiter and Saturn by the UNIVERSITY OF NOTTINGHAM
Pioneers were primitive by comparison.
When the Voyager flybys took place, the
floodgates of data and what were then
deemed to be mind-blowing images
opened. The whole astronomy community endless. It’s now tempting to compare the early ’80s. There’s no doubt that we have a
was stunned. Voyager images with more recent ones, such long way to go to fully understand our Sun
The discoveries of moons, of planetary as looking at Voyager Saturns next to Cassini and family of planets. But the Voyagers will
features, of strange properties of the worlds Saturns, and contemplate the quantum leaps always mark a time when humans took the
we had not yet seen up close, seemed in understanding that have taken place since first big steps to do so. — David J. Eicher

8 ASTRONOMY • OCTOBER 2017