April 1-30, 2017
Explore some of the fascinating features on our Moon.
For GAM2017, we will be running a series of Observing Challenges, developed by The Astronomical League. Whether you are a complete novice to astronomy or a seasoned veteran there will be something for you! Some of the challenges can be done in a night and some will take the whole month.
If you are a sidewalk astronomer or part of an astronomy club you might like to run events to help people complete the challenges. If are planning an Observing Challenge event, don't forget to register your event!
Discuss your observations, ask and answer questions and meet fellow astronomers working on these challenges from around the world in the forum.
Share your photos from this challenge with us and the world on Facebook, or Tweet using #GAM2017 hashtag (@gam_awb).
Lunar Explorations
The search for change on the Moon – a search in vain.
Developed by John Goss of the Astronomical League
People have often fancied that the moon was an active world, even harboring life. Many observers, both professional and amateur, have believed that they stumbled onto to visual evidence suggesting changes occurring on the moon perhaps from vulcanism, perhaps due to life.
In this challenge you will be observing various features on the surface of the Moon that past observers mistakenly believed indicated active changes on the Moon. To help you with your observations, you can find an interactive map of the Moon here. Image of Moon and observers above by Babak Tafreshi.
Share your progress on this challenge with us and the world on Facebook, or Tweet using #GAM2017 hashtag (@gam_awb).
The Astronomical League has also provided a map of each feature to help you find them.
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Best Observing Dates |
Observation Notes |
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Best seen evening: April 5 and 6 |
1671. Several times, Giovanni Domenico Cassini thought he saw a misty formation, perhaps a cloud |
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Best seen evening: April 8 and 9 |
1776. English astronomer William Herschel imagined that the shading variations on the crater floor were caused by the changing shadows of a vast forest of trees that were several times taller than those on Earth. |
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Best seen evening: April 10 and 11 |
1787. German observer Johann Hieronymous Schroeter suspected that a volcano recently formed in the Hevelius crater. |
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Best seen evening: April 28 and 29 |
1791. Schroeter saw changes in the definition of the crater that he thought were possibly due to mist or vegetation. |
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Two-thirds of the distance from Eratosthenes to Schroeter in Sinus Aestruum. |
Best seen evening: April 5 and 6 |
1822. Bavarian observer Franz von Paula Gruithusien saw the layout of a great lunar city, Wallwerk. |
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Best seen evening: April 8 and 9 |
1837. During the Great Moon Hoax, newspaper writer Richard Adams Locke reported that rational beings were said to live there. |
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Best seen evening: April 1 and 30 |
1855. Some observers, led by the renowned observer the Reverend Thomas William Webb, saw a change in their respective configurations. |
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Best seen evening: April 6 and 7 |
1859. Rev. Webb thought it had enlarged its diameter since Schroeter observed it seventy years earlier. |
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Best seen evening: April 1 and 2 |
Circa 1870. French astronomer Jean Chacornac. Fragmentary walls believed to indicated the moon once experienced ocean erosion. |
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Best seen evening: April 6 and 7 |
1869. English amateur astronomer William Radcliffe Birt encouraged his colleagues to closely examine the flat floor of Plato for any signs of change. |
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Best seen evening: April 4 and 5 |
1866. Johann Frederich Julius Schmidt, followed by others, thought that crater Linne had been damaged or transformed. |
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Best seen evening: April 3 and 4 |
1877. Hermann Klein, Director of the Cologne Observatory, found a dark patch near Hyginus crater, one that hadn’t been visible in earlier observations. |
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Best seen evening: April 2 and 3 |
Circa 1900. Suspected snowstorms on the central peak were glimpsed by William Henry Pickering. |
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Best seen evening: April 3 and 4 |
Circa 1900. Suspected snowstorms on the central peak were glimpsed by William Pickering. |
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Best seen evening: April 5 and 6 |
Circa 1900. Pickering attributed indistinct, dark areas on the crater floor to changing vegetation. He believed that he also saw snowstorms on its central peak. |
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Best seen in evening: April 6 and 7 |
Circa 1900. Suspected snowstorms on the central peak were glimpsed by William Pickering. |
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Best seen evening: April 7 and 8 |
Circa 1900. Suspected snowstorms on the peak of this isolated mountain were glimpsed by William Pickering. |
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Best seen evening: April 7 and 8 |
Circa 1900. Some observers saw it as an artificial construct. Suspected snowstorms were glimpsed by William Pickering. | |
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Best seen evening: April 6 and 7 |
1924. William Pickering interpreted shading changes on the crater floor as being due to vegetation growth and migrating swarms of insects. |
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Best seen evening: April 1, 2 and 30 |
1953. New York Herald Tribune science editor John J. O’Neill reported that he observed a twelve mile long natural bridge at the edge of Mare Crisium near the intersection of Promontorium Olivium and Promontrium Lavinium, just east of Proclus crater. Some believed it to be artificial, others saw nothing. |
Sources:
Moore, Patrick, Guide to the Moon, 1953, Eyre and Spottiswoode Publishers
Webb, Rv. TW, 1962, Celestial Objects for Common Telescopes, 6th revision, Dover
Sheehan, William; Dobbins, Thomas, 2001, Epic Moon, Willman Bell
Wood, Charles A., The Modern Moon, 2003, Sky Publishing
Rukl, Antonin, Field Map of the Moon, 2005, Sky Publishing
Birren, Peter, Objects in the Heavens, 2011, Birren Design
