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4 August 2014 sky & telescope

August 2014 VOL. 128, NO. 2

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OBSERVING AUGUST

43 In This Section

44 August’s Sky at a Glance

45 Binocular Highlight

By Gary Seronik

46 Planetary Almanac

47 Northern Hemisphere’s Sky

By Fred Schaaf

48 Sun, Moon & Planets

By Fred Schaaf

50 Celestial Calendar

By Alan MacRobert

54 Exploring the Moon

By Charles A. Wood

56 Deep-Sky Wonders

By Sue French

60 Going Deep

By Ken Hewitt-White

ALSO IN THIS ISSUE

6 Spectrum

By Robert Naeye

11 Letters

12 75, 50 & 25 Years Ago

By Roger W. Sinnott

14 News Notes

18 Cosmic Relief

(^) By David Grinspoon
76 Gallery
86 Focal Point
By Peter McMahon
SKY & TELESCOPE (ISSN 0037-6604) is published monthly by Sky & Telescope Media, LLC, 90 Sherman St., Cambridge, MA 02140-3264,
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FEATURES
20 The Comet Chaser
Europe’s Rosetta mission will be the
fi rst spacecraft to escort a comet
around the Sun and plant a lander on
an awakening nucleus.
By Joel Parker
28 The Forgotten Scientist
Who Solved Lunar Craters
By studying World War I battle-
fi elds, Charles Giff ord developed
the theory that lunar craters were
formed by impacts.
By William Sheehan
34 Toddlers at the Telescope
Have some fun engaging with children
ages 5 and younger at your next star party
with some tools and tips in hand.
By Alice Altair Enevoldsen
38 How To Clean Your Optics
Keeping your telescope and eyepieces
in tip-top condition doesn’t have to be
intimidating or time consuming.
By Gary Seronik
64 Earthgrazing Meteors
When a meteor shower’s radiant is
low, meteors are infrequent but
spectacularly long.
By Don McCarthy
68 Spring into NEAF
The annual Northeast Astronomy
Forum has something for every
amateur astronomer regardless of age,
experience, or fi eld of interest.
By Sean Walker
E
fi
COVER
STORY
ESA / AOES MEDIALAB
On the cover:
The Rosetta
orbiter will
launch a lander
to touch down
on a comet’s
nucleus.
X-RAY: NASA / CXC / SAO; OPTICAL: DETLEF HARTMANN; IR: NASA / JPL-CALTECH