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OSTM/Jason-2

international Earth observation satellite mission

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionMay 17, 2026
Entity authorityQ2658896 ↗
Source-derived summary

OSTM/Jason-2, or Ocean Surface Topography Mission/Jason-2 satellite, was an international Earth observation satellite altimeter joint mission for sea surface height measurements between NASA and CNES. It was the third satellite in a series started in 1992 by the NASA/CNES TOPEX/Poseidon mission and continued by the NASA/CNES Jason-1 mission launched in 2001.

History

Like its two predecessors, OSTM/Jason-2 used high-precision ocean altimetry to measure the distance between the satellite and the ocean surface to within a few centimeters. These very accurate observations of variations in sea surface height — also known as ocean topography — provide information about global sea level, the speed and direction of ocean currents, and heat stored in the ocean.

Jason-2 was built by Thales Alenia Space using a Proteus platform, under a contract from CNES, as well as the main Jason-2 instrument, the Poseidon-3 altimeter (successor to the Poseidon and Poseidon 2 altimeter on-board TOPEX/Poseidon and Jason-1). Scientists consider the 15-plus-year climate data record that this mission extended to be critical to understanding how ocean circulation is linked to global climate change.

OSTM/Jason-2 was launched on 20 June 2008, at 07:46 UTC, from Space Launch Complex 2W at Vandenberg Air Force Base in California, by a Delta II 7320 rocket. The spacecraft separated from the rocket 55 minutes later.

It was placed in a 1,336 km (830 mi) circular, non-Sun-synchronous orbit at an inclination of 66.0° to Earth's equator, allowing it to monitor 95% of Earth's ice-free ocean every 10 days. Jason-1 was moved to the opposite side of Earth from Jason-2 and now flies over the same region of the ocean that Jason-2 flew over five days earlier. Jason-1's ground tracks fall midway between those of Jason-2, which are about 315 km (196 mi) apart at the equator.

Editorial summary

This brief starts where responsible research should: with the source description of “OSTM/Jason-2” as international Earth observation satellite mission. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current lead gives the account dated anchors—1992, 2001, 2008—that can be checked directly. The selected authority fields contribute no independent date. The account is most persuasive where OSTM, Jason-2 and international can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as international Earth observation satellite mission. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated May 17, 2026. The linked authority identifier is Q2658896. None of the 1 selected statements returned an explicit reference. The first chronological checks are 1992, 2001 and 2008.

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Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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Source & attribution

This entry incorporates text from “OSTM/Jason-2” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.