If so they will have meetings and, probably, also chances to look through telescopes and possibly special activities for juniors. Astronomical Society of the Pacific puts out a book called The Universe at Your Fingertips that contains lots of activities to introduce you to astronomy. I am not familiar with Macs. However, the magazine, Sky and Telescope that I mentioned has a column on softward. If you library has it, I suggest that you look through a number of issues for leads about what you want.
Women are now an important part of the astronaut core.
While they still are out-numbered by men, they will have filled every role by this spring. However, in general, NASA has been good for women. Also, conditions change. My advice is to aim for the career you want but make your education broad enough that you can be flexible. My time with NASA Headquarters provided a great experience.