Audience:
Who is the audience?
The audience are teachers, high school students, experts and adults who are interested in the field of astronomy.
Geolocation - where the primary audience lives.
The primary audience lives in the United States, as the missions will be American related.
Age - Specify the age ranges (within a decade) that will primarily be using the site.
The age ranges high schoolers (16-18), college students and adults.
Gender - the gender of the majority of your users.
Both genders would be the majority of my users.
Other - demographics are commonly used to identify the users.
Most likely whites, but other demographics are welcomme as well.