CARTOSAT-2A

CARTOSAT-2A is an Indian Earth observation satellite operated by the Indian Space Research Organisation (ISRO) and cataloged under NORAD ID 32783, with the international designator 2008-021A. Launched on April 28, 2008 (UTC), the spacecraft occupies a near-circular Sun-synchronous orbit and continues to circle the Earth as of the time of writing. It represents a significant step in India's sustained effort to develop indigenous remote sensing capabilities, forming part of one of the world's more prolific national programs for civilian and strategic Earth imaging from space.

Mission and Purpose

CARTOSAT-2A was developed primarily to serve the Earth observation requirements of the Indian Ministry of Home Affairs and a range of other strategic users whose specific needs are not publicly disclosed in catalog records. As the third satellite in the Cartosat series, it follows a lineage dedicated to high-resolution cartographic imaging — providing detailed imagery of the Earth's surface that can be applied to mapping, urban planning, infrastructure monitoring, border surveillance, and land-use analysis.

The Cartosat series is broadly oriented toward photogrammetric and cartographic applications, distinguishing it from some of India's earlier remote sensing satellites that prioritized multispectral medium-resolution imagery. Within this context, CARTOSAT-2A was understood to offer improved imaging performance relative to earlier members of the series, supporting more refined spatial detail useful for the kinds of high-stakes monitoring and planning activities associated with governmental and strategic end-users.

Beyond its cartographic role, the satellite sits within a longer institutional tradition. It holds the distinction of being the thirteenth spacecraft in the Indian Remote Sensing (IRS) satellite series, a program that ISRO has developed over several decades to give India an independent, sovereign capability in space-based Earth observation. The IRS program spans a wide range of applications — from agricultural assessment and water resource management to disaster response and national security — and CARTOSAT-2A's contribution to that program underscores the progression from early experimental platforms toward increasingly capable operational spacecraft. The specific sensors carried by CARTOSAT-2A, and the detailed technical parameters of its imaging payload, are not recorded in the publicly available catalog entries for this satellite, so precise instrument specifications cannot be confirmed here.

Orbit and Tracking

CARTOSAT-2A occupies what is classified as a Sun-synchronous orbit (SSO), a type of near-polar orbit in which the satellite's orbital plane maintains a nearly constant angle relative to the direction of the Sun throughout the year. This geometry ensures that the satellite passes over any given location on Earth at approximately the same local solar time on each revisit, a property that is highly valuable for Earth observation missions because it provides consistent illumination conditions for surface imaging. Shadows fall at similar angles from one pass to the next, making image comparisons over time far more analytically useful than they would be with varying lighting.

The orbital parameters logged in tracking databases describe a nearly circular orbit. The apogee — the farthest point from Earth's surface — stands at approximately 645 km, while the perigee — the closest point — is approximately 627 km, yielding an eccentricity close to zero and confirming the orbit's near-circular character. The satellite's inclination is 97.8° relative to the equatorial plane, which is the hallmark retrograde tilt that enables Sun-synchronous precession: because the orbit leans slightly past 90°, the gravitational oblateness of the Earth causes the orbital plane to drift eastward at a rate that closely matches the Earth's own progression around the Sun.

Each orbit is completed in approximately 97.3 minutes, meaning the satellite completes roughly fourteen to fifteen full revolutions around the Earth in a single day. At an altitude hovering around 630–645 km, the satellite travels at orbital speeds typical of low Earth orbit, covering large swaths of the planet's surface in a relatively short time and enabling frequent revisit opportunities over areas of interest.

CARTOSAT-2A is tracked continuously by the global network of radar and optical sensors that feed into the United States Space Surveillance Network, and its orbital elements are published in two-line element (TLE) format and updated regularly in public catalogs. Its NORAD catalog number, 32783, is the unique identifier used by tracking systems worldwide to distinguish it from the thousands of other objects in Earth orbit. Observers and researchers can use this identifier to retrieve current ephemeris data and compute the satellite's ground track at any given time.

Design and Operator

CARTOSAT-2A was built and operated by the Indian Space Research Organisation, India's national space agency, which has its headquarters in Bengaluru. ISRO is responsible for the full spectrum of the satellite's lifecycle — design, manufacture, launch integration, and on-orbit operations — and the satellite is registered as an Indian government asset. The specific manufacturer of the satellite bus or its subsystems is not recorded in publicly available catalog data.

The satellite was lofted into orbit on April 28, 2008 (UTC), and reached its intended operational orbit successfully. It launched as part of a multi-payload mission, a common arrangement for ISRO's Polar Satellite Launch Vehicle (PSLV) missions during this era, in which the primary satellite is accompanied by a number of smaller co-passengers. The mass of CARTOSAT-2A is not documented in public catalog records.

ISRO's approach to the Cartosat series reflects a broader philosophy within the organization: to develop satellites that serve concrete, operational national needs rather than purely experimental ones. The agency has over the decades built up considerable expertise in Sun-synchronous remote sensing missions, and CARTOSAT-2A represents a mature expression of that expertise, even if some of its technical specifics remain outside the publicly disclosed record.

Significance and Current Status

Within the history of Indian space development, CARTOSAT-2A occupies a meaningful place. As the thirteenth IRS series satellite, it arrived at a moment when India's remote sensing program had fully matured beyond its initial phases and was delivering routine operational services to a wide user community. The IRS program is recognized internationally as one of the more sustained and successful examples of a developing space power building an indigenous, end-to-end Earth observation capability.

The satellite's designation for strategic and Ministry of Home Affairs users signals the degree to which Earth observation from space had, by 2008, become integrated into India's national security and administrative infrastructure. While the cartographic and civilian applications of the Cartosat series are well documented, the operational details of missions tasked to strategic users are naturally kept from the public record, meaning that assessments of mission success or specific accomplishments are difficult to make from open sources alone.

As of the current catalog records, CARTOSAT-2A remains in orbit. No decay or reentry date has been recorded, which is broadly consistent with a satellite at an altitude of roughly 630–645 km, where atmospheric drag is extremely low and orbital lifetimes can extend for many decades without active deorbiting. Whether the satellite remains operationally active — returning useful imagery to its operators — or has reached the end of its functional service life is not confirmed in publicly available data. It is not uncommon for satellites of this vintage to continue occupying their orbits in a semi-operational or residual state long after the primary mission phase concludes.

The Cartosat series itself has continued to grow since CARTOSAT-2A's launch, with ISRO adding progressively more capable spacecraft to the constellation. These later satellites have advanced resolution, improved agility, and expanded capabilities, carrying on the lineage that CARTOSAT-2A helped to establish.

How to Spot It

For observers interested in tracking CARTOSAT-2A from the ground, the satellite's orbital parameters make it accessible to those with basic observation tools, though its brightness will depend on the angle of sunlight reflecting from its surfaces at any given moment. Orbiting at roughly 630–645 km altitude with an inclination of 97.8°, the satellite has a ground track that carries it over virtually all latitudes from the high Arctic to the Antarctic, meaning it is theoretically visible from nearly any location on Earth during appropriate passes.

The best opportunities for naked-eye or binocular observation occur during the hours shortly after local sunset or before local sunrise, when the observer on the ground is in darkness but the satellite, at altitude, is still illuminated by sunlight. During these windows, CARTOSAT-2A may appear as a slow, steady point of light crossing the sky over the course of several minutes. Using the NORAD catalog ID 32783 in any major satellite-tracking application or website will allow observers to generate accurate pass predictions for their specific location, including azimuth, elevation, and timing. Because the satellite follows a Sun-synchronous orbit, passes at similar times of day tend to recur on a predictable pattern, which can assist in planning observation sessions.