ULA Delta II launches with Jason-2 for Europe/US

by Chris Bergin

A United Launch Alliance Delta II (7320-10) launch vehicle has launched with Jason-2 – a European/American Ocean Surface Topography satellite – from SLC-2 at Vandenberg Air Force Base (VAFB), California. Liftoff was confirmed at the opening of the window at 00:46 PDT.

NASASpaceflight.com covered the launch as a live event, with background, images, live updates and a free launch video – all available on the links below (read more).



ULA Delta II/Jason-2 Preview:

ULA’s Delta II 7320-10 configuration involves a two stage vehicle with three solid rocket motors on the first stage and a 10-foot diameter composite fairing.

The satellite – which will be managed by NASA’s Jet Propulsion Laboratory (JPL) in Pasadena – will be placed in an 830-mile-high orbit at an inclination of 66 degrees after separating from the Delta II 55 minutes after liftoff.

Jason-2 will enter orbit below the satellite it is set to eventually replace, Jason-1, after a period of around three weeks. It will maneuver to its operational orbit in order to be ahead of, or behind, Jason-1 by one to ten minutes. It has a lifespan of around five years.

The formation flight of the two satellites will last approximately nine months, which will enable a rigorous comparison and correlation of Jason-2 and Jason-1’s altimetry results.

The Ocean Surface Topography Mission is a joint effort by four organizations including the National Oceanic and Atmospheric Administration (NOAA), NASA, France’s Centre National d’Etudes Spatiales (CNES) and the European Meteorological Satellite Organisation (EUMETSAT) to measure sea surface height by using a radar altimeter mounted on Jason-2.

The Jason-2 project is a response to the international demand for programmes to study and observe oceans and the climate, through a worldwide ocean observation system.

The bird is tasked with extending the time series of ocean surface topography measurements, providing a minimum of three years of measuring global ocean surface topography.

To carry out this mission, Jason-2 will carry a host of CNES and NASA scientific instrumentation – including the next generation Poseidon altimeter, as listed below:

CNES Poseidon-3 altimeter (C- and Ku-band) measures height above sea surface. NASA Advanced Microwave Radiometer (AMR) three-frequency radiometer measures total water vapor along altimeter path to correct for pulse delay.

CNES Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) Doppler tracking antenna receives ground signals for precise orbit determination, satellite tracking, and ionospheic correction data for CNES altimeter.

NASA Global Positioning System Payload (GPSP) receiver provides precise orbit ephemeris data. NASA Laser Retroreflector Array (LRA) works with ground stations to track satellite and calibrate the other satellite location systems, and verify altimeter measurements.

A Time Transfer by Laser Link (T2L2) payload was initially planned to be embarked on MIR in 1999, then with the ACES mission on the International Space Station (ISS).

Under the OSTM (Ocean Surface Topography Mission) program NOAA will provide support from its satellite ground segment capabilities for management of the Jason-2 Satellite flight operations during its routine operational phases and to acquire, produce, and distribute geophysical data in a manner beneficial to all interested users.

While Jason-2 is designed to take over from Jason-1, Eumetsat, NOAA and CNES have already confirmed their commitment for Jason-3 for 2013-2014.

Re-live the launch updates on the live event pages, linked above.

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