Let's try to fill in the blanks and make your description a bit clearer:
* "Some of the 48 aliens have other special features..." What are the other special features? Do they all have the same features, or is it a mix?
* "...42 them curly hairs on top their heads that change colors depending moods..." This is a fun detail! What colors do their hairs change to? Do they change slowly or quickly? Can they control the color changes?
* "...9 knobs that...?" What do the knobs do? Are they on their bodies or their spaceships?
Here are some ideas to expand on your description:
* What are the aliens like? Are they friendly or hostile? What is their culture like?
* What planet are they from? Is it a harsh or hospitable planet?
* What are they doing on Earth? Are they explorers, invaders, or something else entirely?
Remember, the more details you give, the more interesting your alien story will be!