In case anyone else has the same question, here is one someone asked on my IG:
Hola, Im a girl from Puerto Rico and I saw your video of the Nasa intership. I was wondering if the language is a obstacle,Im defende my self in english, but wolf they accept me?!
¡Hola! Mucho gusto conocerte. English was not my first language either when growing up in Puerto Rico but the more I practiced it, especially after being flown to the United States, the better I got. You can learn anything and it's only a matter of time. So do not let that stop you. The great thing about the application and essays is that you can take your sweet time to write it. Así que, puedes escribirlo, pedirle ayuda a tu maestro de inglés, y usar el internet para corregir cositas como la gramática.