178313
Scenarios suggested for the end of the world included the arrival of the next solar maximum , an interaction between Earth and the black hole at the center of the galaxy , or Earth 's collision with a planet called Nibiru .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 None