Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_77 ( right_ascension___j2000__ VARCHAR, apparent_magnitude VARCHAR )

### Question ###
what is the right ascension (j2000) when the apparent magnitude is 13?

### Accurate SQL ###

SELECT right_ascension___j2000__ FROM table_name_77 WHERE apparent_magnitude = 13