This is by no means an exhaustive list of grants and fellowships available to graduate students. This list is provided for convenience, not to imply any authority or expertise on the linked opportunities. For questions, please contact the grant or fellowship coordinator of the particular opportunity in which you are interested.

The Graduate School maintains a more comprehensive list of University sponsored and national opportunities, including travel grants:
https://gradschool.utah.edu/funding/fellowships-scholarships-awards/

Ford Foundation Fellowship (Underrepresented Groups)
nas.edu

Spencer (PER only)
https://naeducation.org/naedspencer-dissertation-fellowship-program/

GRFP (Anyone)
https://www.nsfgrfp.org/

Mirzayan (Summer policy fellowship)
https://www.nationalacademies.org/our-work/the-christine-mirzayan-science–technology-policy-graduate-fellowship-program

DoD Smart (Anyone)
https://www.smartscholarship.org/smart

Utah Space Grant (Astro related)
https://www.utahspacegrant.com/for-students/