Preheat the oven to 350 degrees.

Spray two 8 inch cake pans with baking spray and line the bottom of the pans with parchment paper. Set aside.

In a large bowl combine the flour, baking powder, baking soda, and salt. Mix and set aside.

In another large bowl cream together the butter and sugar. Add in the eggs and vanilla and mix well.

Add half of the flour mixture to the butter mixture and mix until combined.

Add the milk to the butter mixture and mix until smooth.

Add in the remaining flour mixture and mix until just combined, do not over mix.

Fold in the outer space sprinkles. If you don't have these sprinkles mix in a combination of blue, black, silver, and purple sprinkles.

Divide the batter between the two prepared pans and put in the oven.

Bake for 35-40 minutes or until a toothpick inserted into the center comes out clean. Remove from oven and cool 10 minutes. Run a butter knife around the edges and remove the cakes from the pans. Cool completely on wire racks.

To make the frosting place the butter in a large bowl. Beat with a mixer until smooth.

Add in the powdered sugar a cup at a time until the mixture is smooth.

Add in the milk and vanilla and mix until smooth.

Remove 1 cup of frosting and divide between 4 bowls.

Color the large portion of frosting black. In each of the 4 small bowls of frosting color one blue, one purple, one pink, and leave one white.

Place one cake on a cake round. Place 1 cup of black frosting on top of it and smooth it out. Place the second layer of cake on top of the first layer. Cover the cake with black frosting.

Take small teaspoons of each of the blue, purple, pink, and white frostings and dot them all over the top of the cake. Carefully use a butter knife and swirl the colors into the black frosting to create a fun galaxy look. Use more of the colored frosting if you want a brighter galaxy.

Press the sugared planets into the sides of the cake and put a few on top.

Press 1/4 cup of outer space sprinkles around the bottom of the cake.

Place the edible pearls on the sides of the cake, in between the planets, in the shape of constellations.

Write on top of the cake if desired and enjoy!