65940
Since its surface brightness is very low , this deep-sky object is best seen on clear moonless nights and away from city lights .
 moonless
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:
 moonless