In the United States, a wide range of venture capital firms and accelerators support early-stage space startups. Dedicated investors include Space Capital, Space Angels, SpaceFund, and Seraphim Space, while major technology VCs such as Andreessen Horowitz, Sequoia, Lux Capital, Founders Fund, Bessemer, and Khosla Ventures have backed companies across launch, satellites, and data services. This ecosystem is reinforced by accelerators like Techstars Space and Starburst, and by public programmes such as NASA SBIR/STTR, AFWERX, and the Defense Innovation Unit (DIU), which de-risk investments through contracts and grants. Together, these mechanisms illustrate how public-private collaboration drives space sector growth, blending private VC capital with government-backed support.