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FE ATURE S

20 Mars Under the Microscope The largest telescope that ever launched on a planetary mission is revealing the very fabric of the Martian surface. By J. Kelly Beatty

26 The Mysterious Lady on the Moon Is the Moon Maiden on Cassini’s famous 1679 Moon map an astro- nomer’s secret declaration of love? By Françoise Launay and William Sheehan

32 Binocular Showpieces for Light-Polluted Skies Over a bright city or suburb, some sky sights shine through better than others. By Hugh Bartlett

68 Climbing toward the Stars Astrophotography was just one highlight during a 10-day climb of Africa’s tallest mountain. By Shawn Quinn

COVERSTORY

September 2010VOL. 120, NO. 3

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4 September 2010 sky & telescope

On the cover: The HiRISE camera on NASA’s Mars Reconnaissance Orbiter resolves the thin layers near Mars’s north pole.N

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SKY & TELESCOPE (ISSN 0037-6604) is published monthly by Sky & Telescope Media, LLC, 90 Sherman St., Cambridge, MA 02140-3264, USA. Phone: 800-253-0245 (customer service/subscriptions), 888-253-0230 (product orders), 617-864-7360 (all other calls). Fax: 617-864-6117. Website: SkyandTelescope.com. © 2010 Sky & Telescope Media, LLC. All rights reserved. Periodicals postage paid at Boston, Massachusetts, and at additional mailing offices. Canada Post Publications Mail sales agreement #40029823. Cana-dian return address: 2744 Edna St., Windsor, ON, Canada N8Y 1V2. Canadian GST Reg. #R128921855. POSTMASTER: Send address changes to Sky & Telescope, PO Box 171, Winterset, IA 50273. Printed in the USA.

AL SO IN THIS ISSUE

6 Spectrum By Dennis di Cicco

8 Letters

9 50 & 25 Years Ago By Leif J. Robinson

12 News Notes

54 New Product Showcase

66 Telescope Workshop By Gary Seronik

76 Gallery

86 Focal Point By Tim Donovan

THIS MONTH’S SK Y

42 Northern Hemisphere’s Sky By Fred Schaaf

43 September’s Sky at a Glance

45 Binocular Highlight By Gary Seronik

46 Planetary Almanac

48 Sun, Moon, and Planets By Fred Schaaf

50 Exploring the Solar System By Thomas A. Dobbins

56 Celestial Calendar By Alan MacRobert

60 Deep-Sky Wonders By Sue French

64 Going Deep By Ken Hewitt-White

S&T TE S T REPORT

38 Autoguiding Simplified: The SG-4 A black box with one button and one switch. Can autoguiders really be this simple? By Alan Dyer

40 Quick Look: Carina Software’s SkyFi By Ade Ashford

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