Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_52 (lunar_landing_site VARCHAR, duration_on_lunar_surface VARCHAR)
### Question:
Where was the landing site when the duration on the lunar surface was 21:31?
### Answer:
SELECT lunar_landing_site FROM table_name_52 WHERE duration_on_lunar_surface = "21:31"