Transcelestial

Transcelestial is a Singapore-based optical wireless communications (OWC) company founded in 2016 developing miniaturized free-space laser communication terminals for both terrestrial last-mile connectivity and space applications, backed by Y Combinator (W17 batch) and SEEDS Capital.

The company's CENTAURI terminal is a compact, self-aligning free-space optical (FSO) communication system designed to provide multi-gigabit wireless links over distances of several kilometers without spectrum licenses — making it a high-bandwidth alternative to microwave point-to-point links for urban last-mile and backhaul applications in Southeast Asia's dense cities where fiber laying is expensive and slow.

The same core technology — fast-steering mirror (FSM) auto-tracking, single-mode fiber-coupled optics, and APD receiver — applies to inter-satellite links (ISLs) and ground-to-satellite optical links, where Transcelestial is developing next-generation optical communication payloads for LEO smallsats. Singapore's Smart Nation program and the Infocomm Media Development Authority (IMDA) have supported Transcelestial's urban connectivity demonstrations.

For space applications, optical inter-satellite links offer bandwidth hundreds of times greater than RF-based cross-links — enabling constellations like SpaceX Starlink (which added optical ISLs in Gen-2) and OneWeb's planned ISL upgrade to route traffic without ground station dependencies. Transcelestial's commercial trajectory mirrors that of Mynaric (Germany) and TESAT-Spacecom (Germany, subsidiary of Airbus), which have moved from terrestrial FSO to space optical communications.

The company's dual-use (ground and space) technology development strategy lets it build commercial revenue from urban deployments while developing the space-heritage needed for satellite link contracts.