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Increasing in Motion |
  
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Increasing in Motion |
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A planet increases its motion by acceleration from day to day as it approaches perihelion. When it is approaching its apogee, the Moon may advance 12° one day and as much as 13° the next. As its mean motion is 13°10' per day, any excess above this indicates that the Moon is "swift in motion." The condition is regarded as fortunate. Older authorities term it increasing in number.