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_16799784_8 ( diameter__km_ VARCHAR, longitude VARCHAR )

### Question ###
What is the diameter in km of the feature with a longitude of 40.2E?

### Accurate SQL ###

SELECT diameter__km_ FROM table_16799784_8 WHERE longitude = "40.2E"