Merge branch 'main' of https://github.com/AllenDowney/AstronomicalData into main

README.md

@@ -169,4 +169,105 @@ Press this button to run this notebook on Colab:
 
 **Installation instructions**
 
-Coming soon.
+If you plan to run these notebooks on Colab, you don't have to install anything; you can use the links in the
+previous section to open and run them.
+If you want to run the notebooks in your own environment, you might have to do some setup.
+
+You will need to install Python, Jupyter, and some additional libraries.
+If you don't already have Jupyter, we recommend installing Anaconda, which is a Python distribution that 
+contains everything you need to run the workshop code.  It is easy to install on Windows, Mac, and Linux, 
+and because it does a user-level install, it will not interfere with other Python installations.
+
+[Information about installing Anaconda is here](https://www.anaconda.com/distribution/).
+
+If you have the choice of Python 2 or 3, choose Python 3.
+
+Now, there are two ways to get the libraries you need:
+* Option 1: You can install them in an existing Conda environment.
+* Option 2: You can create a new Conda environment.
+
+Installing libraries in an existing environment is simpler, but if you use the same environment for many projects, it will get big, complicated, and prone to package conflicts.
+
+
+**Option 1:** *Installing libraries in an existing Conda environment*
+
+Most of the libraries we need can be installed using Conda, by running the following commands in a Terminal.
+If you are on a Mac or Linux machine, you should be able to use any Terminal.  
+If you are on Windows, you might have to use the Anaconda Prompt, which you can find under the Start menu.
+
+```
+conda install jupyter numpy scipy pandas matplotlib seaborn libopenblas
+conda install -c conda-forge astropy astroquery astro-gala python-wget
+```
+
+In addition, there's one library we can't install with Conda, so we have to use `pip`:
+
+```
+pip install pyia
+```
+
+**Option 2:** *Creating a new Conda environment*
+
+To create a new Conda environment, you'll need to download an environment file from our repository.  On Mac or Linux, you can download it using `wget` on the command line: 
+
+```
+wget https://raw.githubusercontent.com/AllenDowney/AstronomicalData/main/environment.yml
+```
+
+Or you can [download it using this link](https://raw.githubusercontent.com/AllenDowney/AstronomicalData/main/environment.yml).
+
+In a Terminal or Jupyter Prompt, make sure you are in folder where `environment.yml` is stored, and run:
+
+```
+conda env create -f environment.yml
+```
+
+Then, to activate the environment you just created, run:
+
+```
+conda activate AstronomicalData
+```
+
+**Run Jupyter**
+
+If you are not familiar with Jupyter, you can [run a tutorial by clicking here](https://jupyter.org/try).
+Then select "Try Classic Notebook".  It will open a notebook with instructions for getting started.
+Or you can run this [introductory notebook on Colab](https://colab.research.google.com/notebooks/intro.ipynb).
+
+Before you launch Jupyter, [download this notebook](https://raw.githubusercontent.com/AllenDowney/AstronomicalData/main/test_setup.ipynb), which contains code to test your environment.
+
+Or you can use `wget` to download it on the command line, like this:
+
+```
+wget https://raw.githubusercontent.com/AllenDowney/AstronomicalData/main/test_setup.ipynb
+```
+
+To start Jupyter, run:
+
+```
+jupyter notebook
+```
+
+Jupyter should launch your default browser or open a tab in an existing browser window.
+If not, the Jupyter server should print a URL you can use.  For example, when I launch Jupyter, I get
+
+```
+$ jupyter notebook
+[I 10:03:20.115 NotebookApp] Serving notebooks from local directory: /home/username
+[I 10:03:20.115 NotebookApp] 0 active kernels
+[I 10:03:20.115 NotebookApp] The Jupyter Notebook is running at: http://localhost:8888/
+[I 10:03:20.115 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).
+```
+
+In this case, the URL is [http://localhost:8888](http://localhost:8888).  
+When you start your server, you might get a different URL.
+Whatever it is, if you paste it into a browser, you should should see a home page with a list of directories.
+
+Now open the notebook you downloaded and run the cells that contain `import` statements.
+If they work and you get no error messages, **you are all set**.
+
+If you get error messages about missing packages, you can install the packages you need using Conda or `pip`.
+
+If you run into problems with these instructions, let us know and we will make corrections.  Good luck!
+
+