2788
The second rover , named Opportunity , will be launched later this month , and both are expected to arrive at Mars in January .
 The second rover , named Opportunity, Opportunity, both, Mars
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: organization, person, geographical social political, vehicle, location, weapon, facility 
Text: {0} 
Answer:
 The second rover , named Opportunity, Opportunity, both, Mars