STAR ONE D1

Star One D1 (NORAD catalog ID 41904, international designator 2016-082B) is a Brazilian communications satellite operated by Embratel Star One, a subsidiary of telecommunications giant Embratel headquartered in Rio de Janeiro, Brazil. Launched in December 2016 aboard an Ariane 5 ECA rocket from the Guiana Space Centre in French Guiana, the satellite occupies a geostationary orbit above Earth and forms part of Brazil's expanding commercial satellite communications infrastructure. It remains operational in orbit as of the current catalog date.

Mission and Purpose

Star One D1 serves the commercial communications market, providing satellite-based connectivity and broadcast services to customers across the Americas. Embratel Star One is one of Latin America's largest satellite operators, and its Star One fleet represents a sustained national investment in independent orbital communications capacity. The D1 spacecraft joined a family of satellites that collectively serve broadcasting, broadband, corporate networking, and government communications customers throughout the region.

Brazil's reliance on satellite communications is more acute than in many other countries of comparable size, owing to the combination of an enormous geographic footprint, diverse terrain, and vast stretches of territory — particularly within the Amazon basin — where terrestrial network infrastructure remains limited or economically impractical to deploy. Satellites in geostationary orbit are well-suited to bridging these coverage gaps, delivering signals uniformly to large areas without the density of ground-based infrastructure that fiber or cellular networks require.

While the satellite catalog entry maintained by INPE (Instituto Nacional de Pesquisas Espaciais), the Brazilian space agency that formally registers the object, does not specify the precise frequency bands or transponder configuration for Star One D1, commercial geostationary communications satellites of this class are typically equipped with Ku-band and/or C-band transponders that serve both fixed and broadcast applications. The exact mission parameters for this spacecraft have not been disclosed in the public catalog record.

Orbit and Tracking

Star One D1 occupies a geostationary orbit, one of the most strategically important orbital regimes in use today. Its tracked orbital elements place it at an apogee of 35,803 km and a perigee of 35,786 km above Earth's surface — a difference of only 17 km, indicating a very nearly circular orbit. This near-perfect circularity is characteristic of a fully station-kept geostationary satellite that has completed its ascent from the transfer orbit used during launch.

The satellite's inclination is recorded at 0.0°, confirming that it orbits directly above the equatorial plane. This geometry is the defining property of true geostationary orbit: from the perspective of any fixed point on Earth's surface, the satellite appears stationary in the sky, enabling antennas to be permanently pointed at it without the need for active tracking mechanisms. This quality is essential for the continuous, uninterrupted relay services that broadcast and broadband communications require.

The orbital period of Star One D1 is 1,436.1 minutes — just under 24 hours, and closely matching the Earth's own rotational period. This synchrony is what produces the apparent stationary position as seen from the ground. The slight deviation from a perfect 24-hour period reflects the precise dynamics of the orbit as computed from current tracking data rather than an idealized model.

Star One D1 was launched on December 20, 2016 (Eastern Standard Time), corresponding to December 21, 2016 at 20:30 UTC, and has remained in orbit continuously since then. It is cataloged as still in orbit with no decay or reentry date assigned, which is expected for a healthy operational geostationary asset. Satellites in this orbit do not naturally decay on human-relevant timescales; at the end of their service lives, operators typically maneuver them into a slightly higher "graveyard" orbit above the geostationary belt to clear the valuable orbital slot for future use.

Because Star One D1 sits at geostationary altitude — approximately 35,800 km above the surface — it is far beyond the range of most amateur visual satellite observation. It does not appear as a moving point of light crossing the sky in the manner of low Earth orbit satellites. Instead, if visible at all with optical equipment, it would appear as an essentially stationary, very faint point among the stars, requiring a telescope and careful comparison with star charts to identify. No "How to Spot It" guidance is included here, as the satellite is not a practical target for casual visual observation.

Design and Operator

Star One D1 was manufactured by Space Systems/Loral (SSL), a major American satellite manufacturer based in Palo Alto, California, with extensive experience building large commercial communications satellites. The satellite was constructed on SSL's 1300 satellite bus, one of the most widely used commercial satellite platforms in the industry. The SSL 1300 is a modular, high-power bus capable of supporting a wide range of payload configurations, and its heritage across dozens of missions makes it a well-understood and reliable foundation for geostationary communications payloads.

The launch mass of Star One D1 was approximately 6,340 kg at the time of launch — a figure that places it among the heavier commercial communications satellites and reflects both the size of the SSL 1300 bus and the substantial propellant load required for geostationary orbit insertion and years of on-orbit station-keeping. It should be noted that this mass figure derives from background context rather than the official tracking catalog maintained for this object, which does not record a mass value.

The satellite was launched as a co-passenger alongside JCSAT-15, a Japanese communications satellite, aboard an Ariane 5 ECA rocket. This dual-launch configuration is a standard commercial practice for Ariane 5, which is capable of carrying two large geostationary payloads simultaneously, reducing per-kilogram launch costs for both operators. The launch took place from the Centre Spatial Guyanais, the European spaceport located near Kourou in French Guiana — a location chosen for its proximity to the equator, which provides a natural velocity advantage for inserting payloads into geostationary transfer orbits.

Embratel Star One is the commercial satellite operating arm of Embratel, itself a subsidiary of América Móvil, the large Mexican telecommunications conglomerate. The operator manages a substantial fleet of geostationary satellites and has been a significant force in expanding satellite communications access across Latin America. The formal ownership of Star One D1 in international registration is attributed to Brazil, reflecting the national interest in sovereign communications capacity that the satellite represents.

Significance and Current Status

Star One D1 represents a meaningful milestone in Brazil's sustained effort to build and maintain its own geostationary communications infrastructure. Brazil is among a relatively small group of nations that have developed substantial domestic satellite capacity at geostationary altitude, and the Star One fleet has been central to that effort for decades. The D1 satellite, with its large and capable platform, extended the operator's ability to serve the growing demand for broadband and broadcast services across a continent where digital connectivity remains unevenly distributed.

From a broader perspective, Star One D1 is cataloged under the auspices of INPE, which serves as Brazil's national focal point for space object registration and tracking data. INPE's involvement in the cataloging of Brazilian orbital assets reflects the country's engagement with international space law frameworks, including the Registration Convention, under which spacefaring nations are required to provide information about objects they launch into orbit.

The satellite's orbital slot above the equator is a regulated resource, allocated through the International Telecommunication Union's coordination process. Geostationary slots in arcs serving the Americas are in high demand, and Star One D1's position reflects both the operator's historical coordination rights and its ongoing commercial requirements. The satellite's continued presence in orbit, with no reentry date recorded, suggests it is operating within or close to its originally planned service life parameters, though specific operational status details are not publicly available in the tracking catalog.

As of the catalog record used for this article, Star One D1 remains an active member of Brazil's orbital infrastructure, continuing to support the communications needs of a country and region where the practical value of reliable satellite connectivity — for education, emergency services, broadcasting, and business — remains as significant as it was at the time of the satellite's launch.