2007 Q2 | The Moon's age on Einstein's birthday
The 60th anniversary celebrations of King Bhumibol Adulyadej's accession to the throne of Thailand (GMT +07) were held from 8 to 13 June 2006. Photographs of the Moon were taken at the same hour each night.
The six photographs are not reproduced here. They show the disc growing from slightly gibbous (8 to 10 June) to completely lit around 11 June, after which the opposite limb begins to darken again (clearly visible by 13 June).
Assuming that Albert Einstein was born at noon on 14 March 1879, use these data to find the Moon's age (the number of days after new Moon) on his birth date in Germany (GMT +01). Show the method used for the calculation in detail and estimate the error in your result.
Use the synodic month days.
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Reading resources
Material that covers the physics behind this problem.
- An Introduction to Modern AstrophysicsCarroll & Ostlie
The standard reference for olympiad-level astrophysics. Chapters 1-3 cover the celestial sphere, orbits and the magnitude system.
Textbook - Problems from past IOAAInternational Olympiad on Astronomy and Astrophysics
The official archive of every IOAA paper, including all data analysis rounds since 2007 with their solutions and marking schemes.
Past papers - Measurements and their UncertaintiesHughes & Hase
A short, practical guide to error analysis, least squares fitting and chi-square. Exactly the toolkit of the data round.
Textbook