SPACE INDEX COMPANIES INSIGHTS SECTORS PRODUCTS NEWS BLOG ANSWERS RESEARCH ABOUT FOR COMPANIES BUILD / 2026.06.03
CesiumAstro logo CesiumAstro Designs, manufactures, and integrates software-defined phased array communications systems, payloads, and satellites for space, airborne, and ground platforms. vs Phase Four Developed electrodeless radio-frequency and multi-mode electric propulsion systems for satellites Phase Four logo
HEAD-TO-HEAD1 shared sector
CesiumAstro Phase Four
Founded 2017 2015
Headquarters Austin, Texas, USA Hawthorne, California, USA
Type private private
Status operating closed
Employees 318 5
Total funding $710.2M $35.8M
Latest round Series C Series C
Sectors Satellite Components & Subsystems, Satellite Communications, Satellite Manufacturing Space Propulsion, Satellite Components & Subsystems
Products listed 15 4
Federal contracts
Launches
Leaders listed Shey Sabripour, Kenneth Smith, Chris Pappas III Steve Kiser, M. Umair Siddiqui, Simon Halpern
News mentions 26 0
SHARED SECTORS
FREQUENTLY ASKED

How do CesiumAstro and Phase Four compare?

Both companies work in Satellite Components & Subsystems. CesiumAstro was founded in 2017 and Phase Four in 2015.

Which is larger, CesiumAstro or Phase Four?

CesiumAstro reports the larger workforce, with 318 employees versus 5.

Numbers refresh on every render against the live Space Index database. Federal contract data from USAspending.gov; launches from LaunchLibrary2.