diff --git a/1. Astropy basics.ipynb b/1-Astropy-basics.ipynb similarity index 100% rename from 1. Astropy basics.ipynb rename to 1-Astropy-basics.ipynb diff --git a/2. FITS.ipynb b/2-FITS.ipynb similarity index 100% rename from 2. FITS.ipynb rename to 2-FITS.ipynb diff --git a/3. PyVO.ipynb b/3-PyVO.ipynb similarity index 100% rename from 3. PyVO.ipynb rename to 3-PyVO.ipynb diff --git a/4. Barnards star.ipynb b/4-Barnards-star.ipynb similarity index 100% rename from 4. Barnards star.ipynb rename to 4-Barnards-star.ipynb