Lunar Explorations

The search for change on the moon – a search in vain.

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 visual evidence suggesting changes occurring on the moon, perhaps from vulcanism, perhaps due to life.

Feature:	Observation Notes:	Map (PDF)
1. Between the craters Walther and Gauricus. Best seen: April 11 & 12 in the evening sky; and April 23 in the morning sky. 2. Gassendi, crater. Best seen: April 13 & 14 in the evening sky; and April 25 in the morning sky.	1. 1671. Several times, Giovanni Domenico Cassini thought he saw a misty formation, perhaps a cloud. 2. 1776. English astronomer William Herschel imagined that the shading variations on the crater floor were caused by the changing shadows of a vast forest containing trees that were several times taller than those on Earth.	Click on the image to print/view PDF
3. Hevelius, crater. Best seen: April 16 in the evening sky and April 28 in the morning. 4. Alhazen, crater. Best seen: April 5 in the evening sky.	3. 1787. German observer Johann Hieronymous Schroeter suspected that a volcano recently formed in the Hevelius crater. 4. 1791. Schroeter saw changes in the definition of the crater that he thought was possibly due to mist or vegetation.	Click on the image to print/view PDF
5. Two-thirds of the distance from Eratosthenes to Schroeter in Sinus Aestruum. Best seen: April 11 & 12 in the evening sky; and April 23 and 24 in the morning. 6. Sinus Iridum. Best seen: April 13 in the evening sky; and April 24 & 25 in the morning sky.	5. 1822. Bavarian observer Franz von Paula Gruithusien saw the layout of a great lunar city, Wallwerk. 6. 1837. During the Great Moon Hoax, newspaper writer Richard Adams Locke reported that rational beings were said to live there.	Click on the image to print/view PDF
7. Messier and Messier A, craters. Best seen: April 5 in the evening sky, and April 18 in the evening and morning sky. 8. Cichus, crater in Mare Nubium. Best seen: April 11 and 12 in the evening sky; and April 23 in the morning sky.	7. 1855. Some observers, led by the renowned observer the Reverend Thomas William Webb, saw a change in their respective configurations. 8. 1859. Rev. Webb thought it had enlarged its diameter since Schroeter observed it seventy years earlier.	Click on the image to print/view PDF
9. Fracastorius, crater. Best seen: April 6 and 7 in the evening sky; and April 20 in the morning sky. 10. Plato, crater. Best seen: April 11 in the evening sky; and April 23 in the morning.	9. Circa 1870. French astronomer Jean Chacornac. Fragmentary walls believed to have formed from oceanic erosion. 10. 1869. English amateur astronomer William Radcliffe Birt encouraged his colleagues to closely examine the flat floor of Plato for any signs of change.	Click on the image to print/view PDF
11. Linne, small crater. Best seen: April 9 in the evening sky; and April 22 in the morning sky. 12. Hyginus N, near crater Hyginus along Rima Hyginus. Best seen: April 8 and 9 in the evening sky; and April 21 and 22 in the morning sky.	11. 1866. Johann Frederich Julius Schmidt, followed by others, thought that crater Linne had been damaged or transformed. 12. 1877. Hermann Klein, Director of the Cologne Observatory, found a dark patch near Hyginus crater, one that hadn’t been visible in earlier observations.	Click on the image to print/view PDF
13. Theophilus, crater. Best seen: April 8 in the evening sky; and April 21 in the morning sky. 14. Plinius, crater. Best seen: April 8 in the evening sky; and April 21 in the morning sky.	13. Circa 1900. Suspected snowstorms on the central peak were glimpsed by William Henry Pickering. 14. Circa 1900. Suspected snowstorms on the central peak were glimpsed by William Pickering.	Click on the image to print/view PDF
15. Alphonsus, crater. Best seen: April 10 in the evening sky; and April 23 in the morning sky. 16. Bullialdus, crater. Best seen: April 12 in the evening sky; and April 25 in the morning sky.	15. 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. 16. Circa 1900. Suspected snowstorms on the central peak were glimpsed by William Pickering.	Click on the image to print/view PDF
17. Mons Pico, lone mountain. Best seen: April 11 in the evening sky; and April 23 in the morning sky. 18. Montes Recti, straight mountain range. Best seen: April 12 in the evening sky; and April 24 in the morning sky.	17. Circa 1900. Suspected snowstorms on the peak of this isolated mountain were glimpsed by William Pickering. 18. Circa 1900. Some observers saw it as an artificial construct. Suspected snowstorms were glimpsed by William Pickering.	Click on the image to print/view PDF
19. Eratosthenes, crater. Best seen: April 11 in the evening sky; and April 24 in the morning sky. 20. O’Neill’s Bridge, mistaken formation. Best seen: April 5 and 6 in the evening sky and April 18 in the morning sky.	19. 1924. William Pickering interpreted shading changes on the crater floor as being due to vegetation growth and migrating swarms of insects. 20. 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.	Click on the image to print/view PDF