Public satellite datasets: launch, orbit, position, and operational status

Research date: 2026-10-20. Focus: artificial satellites orbiting Earth, with launch records and historical information where useful. “Public” includes services that require registration; access and reuse conditions differ.

The most practical starting combination is CelesTrak GP + CelesTrak SATCAT + GCAT: orbital elements, broad operational classifications, and launch/mission context. Add Space-Track for orbital history, SatNOGS for radio reception evidence, and operator notices for service availability. This combination is a recommendation based on the coverage below; none of the reviewed sources provides complete, continuously verified spacecraft health for every satellite.

What the requested data means

GP means General Perturbations; TLE means Two-Line Element set; OMM means Orbit Mean-Elements Message. GP elements require the compatible SGP4 propagation model; treating them as ordinary Keplerian elements produces different results. Position quality also depends on element age. CelesTrak format definitions, Skyfield satellite documentation

Dataset comparison

“Calculate” means positions must be derived locally. “Subset” means coverage is limited to participating missions or constellations.

Main sources

CelesTrak: easiest starting point for tracking and broad status

GP supplies epoch, mean motion, eccentricity, inclination, node, argument of perigee, mean anomaly, and drag-related fields. Choose JSON/CSV or OMM XML/KVN for new work. CelesTrak reports that its five-digit catalog range was exhausted in July 2026; its legacy TLE output cannot represent newly cataloged objects above 99999. GP retrieval should be cached and occur at most once every two hours under the documented policy. GP formats and usage

SATCAT adds NORAD_CAT_ID, OBJECT_ID, OBJECT_TYPE, OPS_STATUS_CODE, owner, launch date/site, decay date, and summary orbit values. The full CSV supports bulk enrichment; records.php supports filtered JSON/CSV. These orbital summaries do not describe an exact launch insertion state. SATCAT schema

Preserve the operational codes rather than reducing everything to an active/inactive flag:

CelesTrak defines active as +, P, B, S, or X. It explicitly allows active status without power or communications, for example passive geodetic satellites. Consequently, this flag cannot establish live radio or commercial service availability. Status definitions

SupGP derives elements from operator-supplied ephemerides, almanacs, or state vectors for participating fleets. It can help with early deployment and maneuvering spacecraft. Available sources include SpaceX, OneWeb, Planet, Iridium, ISS, and others; some prelaunch sets are predictions. SupGP sources

SupGP can return multiple records for one object, including separate epochs or sources. Select the segment appropriate to the requested time and retain its provenance. It is not always safe to keep only one row per satellite. SupGP query and epoch rules

Space-Track: orbital history and official catalog access

Use gp for the latest public element set, gp_history for historical elements, and satcat for catalog metadata. Decay/reentry products help distinguish objects still in space from reentered objects. A valid registered account is required; some objects lack public or timely elements.

The documented ceilings are fewer than 30 requests/minute and 300/hour, with stricter product retrieval schedules: GP once/hour and SATCAT once/day. Download historical ranges once, retain them, and batch object queries.

The current documentation grants redistribution of basic SSA products with appropriate citation; apply the relevant agreement to other products. Space-Track and CelesTrak often share the same underlying surveillance data, so agreement between them is not independent confirmation. API, availability, and sharing documentation

GCAT: strongest general source for launch and lifecycle context

Jonathan McDowell’s General Catalog of Artificial Space Objects connects objects, payloads, launches, launch vehicles, sites, and organizations. Downloadable TSV tables and bulk archives make it useful for research joins. The site showed a 2026-10-17 data update when checked. Reuse is under CC BY 4.0, with attribution. Include the extended catalogs for catalog numbers above 100000. Catalog and downloads

The launch database covers successful orbital launches and confirmed failed orbital attempts, including UTC launch times where available. Some numerical vehicle parameters are estimates; preserve their uncertainty. Launch database documentation

For operational history, payload tables distinguish TLast (last known active), TOp (end of regular operations), and TDate (end of transmission), with flags for uncertainty or continued beacon transmission. Payload field definitions

The active catalog is not a live health feed: its maintainer explicitly describes activity updates as infrequent and sometimes uncertain. Its perigee/apogee/inclination describe a representative early operational orbit, so use a fresh tracking feed for current location. Active-catalog limitations

ESA DISCOSweb: physical characteristics and space-object history

DISCOS contains launch and registration information, vehicle descriptions, spacecraft size/mass/shape, owners, mission objectives, and orbit histories. DISCOSweb exposes a public-facing subset through a web interface and API, making it valuable for object characterization. Do not assume every internal DISCOS field or history is publicly downloadable. ESA’s description of DISCOS and its API

The current API documentation redirected to ESA’s account sign-in during this review. Authentication, available fields, quotas, and reuse terms should therefore be checked after registration; authenticated data retrieval was not tested. The old Operations API is explicitly discontinued and points to DISCOSweb.

SatNOGS DB: radio reception and transmitter evidence

SatNOGS is a community database particularly useful for radio-equipped satellites. Its public API has satellite, transmitter, telemetry, and TLE resources. Current satellite fields include status, launched, deployed, decayed, updated, reception_status, and reception_evidence. The sample ISS response returned status: "in orbit" and a separate reception_status: "Unknown"; orbital presence and reception must remain separate. Live API schema

Reception evidence can support an activity assessment, but a heard beacon does not establish full mission capability, and lack of reception does not establish failure. Coverage depends on observations and contributions. The API documentation specifies CC BY-SA 4.0 and open access. API access and license

Launch Library 2: launch events and target-orbit context

The Space Devs maintain launch history and schedules, including vehicles, providers, pads, launch windows, mission descriptions, and outcomes. A checked detailed response included net, window_start, window_end, last_updated, rocket, pad, status, and mission.orbit. net means no earlier than; target orbit categories do not provide numerical insertion states. API documentation

Unauthenticated access allows 15 calls/hour per IP. The production version checked was 2.3.0, with plural paths such as /launches/upcoming/. Updates follow new information, often several times an hour during launches. The lldev service uses stale, limited data for development. A successful launch is evidence about insertion, not the satellite’s subsequent health. Maintainer FAQ

N2YO: convenient calculated current coordinates

N2YO’s positions endpoint returns calculated latitude, longitude, altitude, timestamps, and observer-relative look angles. Its first result corresponds to current UTC time, followed by one-second samples for up to 300 seconds. This is convenient when avoiding local propagation; it is a derived service rather than a raw observation dataset.

A free account and API key are required. Published hourly limits include 1,000 positions calls, 1,000 TLE calls, and 100 calls each for visual passes, radio passes, and “above.” The service also supports numerical IDs above 100000. API reference

Use the provider’s terms for reuse conditions; free API access is not an explicit open-data license. No key-based request was made during this review.

Historical, registration, and specialist sources

UCS Satellite Database: useful downloadable mission metadata, including purpose, operator, manufacturer, launch date, mass, power, expected lifetime, and orbit summaries. However, updates are paused and the data is current only through 2023-05-01. Its 7,560-operational-satellite total describes that snapshot, not today’s fleet. Retain the snapshot date if using its labels. Database, downloads, and update notice

UNOOSA Online Index: state-submitted registration information provides designators, launch/registry context, general function, and basic reported orbit parameters. It is useful for registration provenance, rather than current tracking. The current search page limits coverage to functional space objects; “functional” here describes object scope and should not be read as a live health judgment. Current index, registration resources and document indexes

IGS: precise GNSS orbit products are a better fit for high-precision navigation-satellite research than general catalog elements. SP3 files contain time-tagged ephemerides. Ultra-rapid products combine observed and predicted arcs and update every six hours; rapid and final products arrive later. Select by constellation, validity interval, and latency. These products do not cover the general satellite population. Products and access links, format specifications

Operator status notices: for GPS, use USCG NAVCEN’s constellation status and NANU/operational advisory definitions. For Galileo, the GSC constellation table links usability labels to active NAGUs. These describe service availability for their constellations and can supplement a general catalog status.

Useful entry points

Cache downloaded data and follow each provider’s documented retrieval schedule. The N2YO URL follows its documented path syntax and requires a user-generated key.

Combining the datasets

Suggested implementation, inferred from the source coverage:

1. Build an object inventory from SATCAT; select Earth-orbiting payloads when the goal excludes rocket bodies and debris. Preserve unknown classifications.
2. Attach launch and mission metadata from GCAT and, when needed, LL2 or DISCOS. Preserve each provider’s object and launch identifiers.
3. Retrieve fresh GP or suitable operator/SupGP data. Compute a position for the requested UTC time, or request N2YO coordinates for a small application.
4. Keep catalog status, mission activity, reception evidence, and operator service status as separate fields, each with its source and observation/update time.

Recommended fields for a combined research table:

Use the NORAD catalog ID where available, with support for more than five digits. Retain the full designator including its piece suffix: a launch prefix identifies a group of objects. GCAT’s JCAT is its own identifier system, so use its documented relationships/crosswalks rather than assuming every identifier is interchangeable. Avoid joining on names alone. GCAT identifier conventions

For local position calculation, SGP4 produces a state in the TEME frame; convert through an appropriate Earth-fixed frame before reporting geodetic coordinates. Store the requested time and element epoch separately. Skyfield documents propagation, coordinate conversion, and WGS84 subpoints. Historical analyses need elements near the historical time, rather than today’s elements propagated arbitrarily far backward. Position calculation and epoch guidance

Limitations that affect research results

• Initial orbit is not necessarily injection orbit. GCAT’s representative early orbit, a target orbit category, and the first published GP set are different measurements. A complete public archive of exact injection state vectors was not identified; obtain mission-specific operator data when that distinction matters.
• Fresh retrieval does not guarantee fresh observations. Preserve element epoch and record-update time separately from download time. Do not assign a universal accuracy to every satellite.
• Presence is not health. An object can remain tracked long after mission failure, or transmit a beacon after regular operations end. A passive satellite can still perform its mission without transmissions.
• Coverage and source dependence matter. Public catalogs omit or delay some objects, and derived services often share upstream data. Preserve missing values and uncertain identifications, especially immediately after rideshare deployment.

What was verified

Provider documentation and public pages were reviewed on the research date. Direct, unauthenticated sample requests returned HTTP 200 for CelesTrak GP JSON, CelesTrak SATCAT JSON, SatNOGS ISS JSON and its live schema, GCAT active TSV, LL2’s one-record detailed response, and the current UNOOSA search-page HTML. This checks access and sample structure, not completeness of every dataset or the results of UNOOSA’s interactive search.

Space-Track’s authenticated API, DISCOS authenticated data, N2YO key-based calls, and IGS archive downloads were not exercised. No complete satellite dataset or continuous location feed is bundled with this note; the links above retrieve provider-maintained data.