---
type: claim
domain: space-development
description: "Space-drawn ZBLAN offers 10x the capacity of silica fiber and could replace inline optical repeaters every 40-50 km in submarine cables with 400-5000 km spacing"
confidence: likely
source: "Astra, web research compilation February 2026"
created: 2026-02-17
depends_on:
  - "microgravity eliminates convection sedimentation and container effects producing measurably superior materials across fiber optics pharmaceuticals and semiconductors"
  - "the space manufacturing killer app sequence is pharmaceuticals now ZBLAN fiber in 3-5 years and bioprinted organs in 15-25 years each catalyzing the next tier of orbital infrastructure"
sourced_from:
- inbox/archive/2026-02-17-astra-microgravity-manufacturing-deep-dive.md
---

# ZBLAN fiber optics produced in microgravity could eliminate submarine cable repeaters extending signal range from 50 km to potentially 5000 km

ZBLAN (zirconium barium lanthanum aluminium sodium fluoride) is an optical fiber with extraordinary transparency across a broader wavelength range than silica, especially in the mid-infrared (2-4 micron wavelengths). On Earth, gravity-driven convection during cooling creates microcrystalline defects that degrade performance. In microgravity, these defects are suppressed or eliminated.

**The attenuation numbers.** ZBLAN has a theoretical minimum attenuation of 0.001 dB/km at 2 microns wavelength, compared to silica's best of 0.2 dB/km. Terrestrial ZBLAN achieves only 0.7 dB/km due to gravity-induced defects. If space-made ZBLAN approaches its theoretical limit, a 2,000 km length could match the optical loss of just 10 km of silica fiber. Current submarine cables require inline optical repeaters every 40-50 km. ZBLAN could extend that to 400-5,000 km, fundamentally restructuring the economics of global telecommunications.

**Production breakthrough.** Flawless Photonics produced nearly 12 km of ZBLAN on the ISS in February-March 2024 -- a 600x improvement over previous efforts that managed only ~20 meters per attempt. They completed eight separate draws each exceeding 700 meters (standard commercial spool length). Selected for ESA's Advanced Materials and In-orbit Manufacturing Industry Accelerator in January 2026.

**Market economics.** Terrestrial ZBLAN fiber sells for $150-$3,000 per meter depending on quality, with premium grades at ~$1,000/meter. Space-made ZBLAN is projected at $600K-$3M per kilogram. Total addressable market estimated at EUR 260-350 million annually (10-13% of specialty fiber market). Revenue per kg vastly exceeds launch costs.

## Evidence
- Theoretical attenuation: 0.001 dB/km (ZBLAN) vs 0.2 dB/km (silica) — 200x theoretical advantage
- Flawless Photonics — 12 km on ISS, 600x improvement over prior efforts
- Submarine cable repeater economics — 40-50 km spacing vs potential 400-5,000 km

## Challenges
Optical quality advantage of space-produced ZBLAN has not been publicly quantified with hard attenuation numbers as of early 2026. If improvement is only 2-3x rather than 10-100x, the commercial case weakens significantly. Autonomous process control at required precision remains an engineering challenge.

---

Relevant Notes:
- [[microgravity eliminates convection sedimentation and container effects producing measurably superior materials across fiber optics pharmaceuticals and semiconductors]] — ZBLAN is the highest-value near-term example of this physics advantage
- [[the space manufacturing killer app sequence is pharmaceuticals now ZBLAN fiber in 3-5 years and bioprinted organs in 15-25 years each catalyzing the next tier of orbital infrastructure]] — ZBLAN is Tier 2, first physical product driving permanent orbital platforms

Topics:
- [[space exploration and development]]
