21,600 is the rule not the circumference of earth.The reason that the Jules Verne starts and finishes where it does is that it gives a course length of 21,600 miles - which is the circumference of the planet
• To sail around the World, a vessel must start from and return to the same point, must cross all meridians of longitude and must cross the Equator. It may cross some but not all meridians more than once (i.e. two roundings of Antarctica do not count). The shortest orthodromic track of the vessel must be at least 21,600 nautical miles in length calculated based on a ‘perfect sphere’. In calculating this distance, it is to be assumed that the vessel will sail around Antarctica in latitude 63 degrees south.
• A vessel starting from any point where the direct orthodromic distance is too short shall pass one single island or other fixed point on a required side so as to lengthen his orthodromic track to the minimum distance.
• No starting point will be permitted more south than 45° south.
• 1 degree of longitude at 63° south will be taken as 27.24NM
As the independent authority established by World Sailing to provide standards and accuracy for record attempts, the WSSRC offers Performance Certificates for achievement in non-recognized categories, and world records for achievement in established categories.
Larson reports the WSSRC would award Performance Certificates for:
• First African American
• Fastest American
• First American Multihull
• 6th Person to solo non-stop in Multihull
Additionally, among the possible achievement for completing the voyage, Larson is seeking world records for:
• Fastest Solo Non-Stop Around the World Outright – 40 days
• Fastest Solo Non-Stop Around the World 60ft Anytime (Multihull) – no current record
• Intermediate Records (ex. Equator to Equator) – 29 days
How large is Earth?Earth's circumference (the distance all the way around the equator) is 24,901 miles (40,075 kilometers). Its diameter (the distance from one side to the other through Earth's center) is 7,926 miles (about 12,756 kilometers). Earth is slightly smaller when measured between the North and South Poles which gives a diameter of 7,907 miles (12,725 kilometers). Earth bulges out a bit more around the equator than around the poles because of its rotation (spin).
even though they say it is an oblate spheroid, The"photos" of earth show a perfect sphere...