Orbital Imaging

Sensor types

How Earth Observation Satellites See: Optical, Radar, and Hyperspectral

Three sensor families, three different physics, three different markets.

Optical (electro-optical / visible + near-infrared). Works like a camera — captures reflected sunlight in visible and near-infrared bands. Produces the imagery most people recognize: cities, forests, coastlines, clouds. Resolution ranges from 30 cm (military-grade, Vantor/Airbus) to 3–5 m (Planet SuperDove). Limitation: requires daylight and clear skies. Clouds, nighttime, and smoke block the view. Optical accounts for 47% of EO revenue.

Synthetic Aperture Radar (SAR). The satellite emits its own microwave signal and measures the return. Works through clouds, at night, in rain, in smoke. Resolution down to 25 cm (ICEYE spotlight mode). SAR detects surface texture and moisture — it can find ships in fog, measure building subsidence in millimeters, detect oil slicks, and monitor soil moisture. Limitation: SAR images are harder to interpret than optical; processing is computationally expensive; and speckle noise requires filtering. SAR is the fastest-growing EO sensor segment.

Hyperspectral. Captures hundreds of narrow spectral bands rather than the 4–8 broad bands of multispectral sensors. This reveals chemical composition: specific minerals in rock, crop stress before it is visible, water quality indicators, gas leaks. Resolution is typically 5–10 m. Limitation: enormous data volumes (150–300 bands per pixel) require specialized analytics. Hyperspectral is the newest commercial segment, with Pixxel (India) and Satellogic (Argentina) leading the field.

Optical operators

Commercial Optical Earth Observation Constellations

Planet scans the whole planet daily. Vantor and Airbus resolve individual vehicles.

Planet Labs reported ~$244M revenue in FY2025. Planet holds the $280M German government environmental monitoring contract (July 2025). Vantor (rebranded from Maxar Intelligence in 2025) holds NRO EOCL contracts worth billions distributed to hundreds of thousands of US government users. Airbus supplies the Copernicus Contributing Missions and French defense. BlackSky holds a $50M DoD contract.

SAR operators

Commercial Synthetic Aperture Radar Constellations

Sees through clouds, works at night, measures surface change in millimeters.

In August 2026, the NRO awarded operational Radar Commercial Augmentation (RCA) contracts to all three US SAR providers — Capella, ICEYE US, and Umbra — after a four-year evaluation. These are operational imagery contracts, not research awards. ICEYE launched six SAR satellites in March 2026 alone, including two for the Polish Armed Forces MikroSAR program. Capella was acquired by IonQ. SAR microsatellites weigh 65–112 kg — small enough that a single Falcon 9 rideshare can deploy a dozen.

Hyperspectral & VLEO

Emerging Sensor Types: Hyperspectral Imaging and Very Low Earth Orbit

More bands, lower altitude, sharper answers.

Pixxel (India). Operates the world’s highest-resolution commercial hyperspectral constellation. Six Firefly satellites in orbit as of early 2026, imaging at 5 m resolution across 150+ spectral bands (VNIR) with a 40 km swath. Next-generation Honeybee satellites add SWIR (short-wave infrared) bands, targeting an 18-satellite constellation by 2027. ~$210M raised (Series B, December 2024). Customers in agriculture, mining, oil & gas, defense. NASA CSDA contract. Google is an investor.

Satellogic (Argentina). ~60 satellites in orbit, each carrying both multispectral (70 cm) and hyperspectral imagers. “Constellation-as-a-Service” model — governments and enterprises can lease dedicated satellite capacity. Partnership with Maxar/Vantor for tasking API integration. $424M raised; public via SPAC (January 2022) at $850M valuation; current market cap ~$92M.

Albedo (US). VLEO imaging pioneer. Clarity-1 satellite on orbit since March 2025, operating below 300 km altitude. 10 cm visible resolution and 2 m thermal infrared — previously achievable only from aircraft. NRO and AFRL data contracts. The physics: halving the distance to the ground makes an optical sensor four times more perceptive. See the VLEO section on the Launch Market page for more operators and the demand dynamics.

GHGSat (Canada). Specialized constellation for greenhouse gas monitoring — methane and CO&sub2; emissions from individual facilities, measured from orbit. Serves energy companies, regulators, and carbon markets.

Muon Space (US). Microwave radiometry constellation for climate data — atmospheric temperature and moisture profiles, sea surface temperature, soil moisture. Fills gaps that optical and SAR cannot.

China

Chinese Earth Observation Constellations

The largest commercial imaging fleet outside the United States.

Jilin-1 (Chang Guang Satellite Technology, Changchun). China’s largest commercial EO constellation and the largest sub-meter imaging fleet in orbit. 130 satellites launched since October 2015; 63 tracked as active in August 2026. Commercial imagery at 0.5 m and 0.75 m resolution in four spectral bands (R, G, B, NIR) plus wide-swath (136 km) and video (1 m) variants. Target: 300 satellites for near-persistent global optical coverage. $375M in government funding (2020). Chang Guang spun out of the Chinese Academy of Sciences optics institute. Jilin-1 imagery has been used for commercial agriculture, urban planning, and disaster response — and has also been identified as providing operational intelligence on US military deployments in the Middle East (March 2026, per US officials).

Gaofen / CHEOS (state). China’s High-resolution Earth Observation System — a multi-satellite national program with optical, SAR, and multispectral sensors from sub-meter to wide swath. Government-operated, not commercially sold (though data is shared with allies and Belt and Road partners).

SuperView / GaoJing (China Siwei). Commercial very-high-resolution optical constellation at 0.5 m. 16 SuperView Neo satellites on order as of 2025. Operated by China Siwei, the commercial imagery arm of China Aerospace Science and Technology Corporation (CASC).

Zhuhai Orbita. Commercial hyperspectral and video EO constellation based in Zhuhai. 12+ satellites in orbit.

Space telescopes

Outward-Looking: Space Telescopes in Earth Orbit

Not all imaging from orbit points down.

Earth orbit also hosts the largest astronomical observatories ever built. These are not Earth observation platforms — they point outward at the universe — but they are assets in the regime, subject to the same orbital mechanics, debris environment, and servicing constraints as everything else on this page. The distinction matters because space telescopes at L2 (JWST, Euclid, the upcoming Nancy Grace Roman) are not in Earth orbit and are covered elsewhere.

Hubble remains operational after 36 years in LEO, though it is down to one working gyroscope and its science operations contract was extended through June 2026 (further extensions likely). It orbits at ~540 km and is slowly losing altitude; without a reboost, it will reenter in the 2030s. SpaceX and the Polaris program studied a Dragon-based reboost mission; no decision has been made. Hubble has no replacement in Earth orbit — its successor for deep-field work is JWST at L2.

Xuntian is the most significant upcoming Earth-orbit telescope. A 2 m primary mirror (slightly smaller than Hubble) but with a field of view 300× larger, a 2.5-billion-pixel survey camera, and five instruments spanning UV to near-IR. It will co-orbit with Tiangong at ~400 km, enabling periodic docking for refueling, servicing, and instrument upgrades by Chinese astronauts — a maintenance architecture Hubble once had (Shuttle servicing missions) and lost. Planned 10-year mission; docking-based servicing could extend it for decades. Launch on Long March 5B, targeted early 2027 after delays from the original 2023 date.