SPACE INDEX COMPANIES INSIGHTS SECTORS PRODUCTS NEWS BLOG ANSWERS RESEARCH ABOUT FOR COMPANIES BUILD / 2026.06.03
Busek logo Busek Designs and manufactures electric propulsion systems for spacecraft, including Hall effect, electrospray, RF ion, and green monopropellant thrusters vs Phase Four Developed electrodeless radio-frequency and multi-mode electric propulsion systems for satellites Phase Four logo
HEAD-TO-HEAD2 shared sectors
Busek Phase Four
Founded 1985 2015
Headquarters 11 Tech Circle, Natick, MA 01760 Hawthorne, California, USA
Type private private
Status operating closed
Employees 107 5
Total funding $200K $35.8M
Latest round Grant Series C
Sectors Space Propulsion, Satellite Components & Subsystems Space Propulsion, Satellite Components & Subsystems
Products listed 9 4
Federal contracts
Launches
Leaders listed Vlad Hruby, James Szabo, John Meikle Steve Kiser, M. Umair Siddiqui, Simon Halpern
News mentions 0 0
SHARED SECTORS
FREQUENTLY ASKED

How do Busek and Phase Four compare?

Both companies work in Space Propulsion, Satellite Components & Subsystems. Busek was founded in 1985 and Phase Four in 2015.

Which is larger, Busek or Phase Four?

Busek reports the larger workforce, with 107 employees versus 5.

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