86836
Prior to 1920 , all ships kept solar time on the high seas by setting their clocks at night or at the morning sight so that , given the ship 's speed and direction , it would be 12 o'clock when the sun crossed the ship 's meridian .
 solar time
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 solar time