Cluster of satellites meets Soyuz launcher in French Guiana

The three-stage Soyuz rocket rolled out to its launch pad in French Guiana on Tuesday, three days before liftoff. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
The three-stage Soyuz rocket rolled out to its launch pad in French Guiana on Tuesday, three days before liftoff. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon

Five European satellites packaged inside an aerodynamic fairing have joined a Soyuz rocket its launch pad in the French Guiana jungle for a roaring ride into orbit Friday.

Headlined by Sentinel 1B, the second radar-equipped environmental surveillance satellite for Europe’s multibillion-dollar Copernicus Earth observing system, the five spacecraft are scheduled for launch at 2102:13 GMT (5:02:13 p.m. EDT) Friday from the Guiana Space Center on the northeastern shore of South America.

Technicians raised the satellites — attached to a Russian-made Fregat upper stage inside the Soyuz nose shroud — on top of the rocket Tuesday, several hours after the launcher emerged from its integration hangar and rode to the launch pad aboard a specialized rail car.

The Soyuz booster made the 700-meter (2,300-foot) journey Tuesday morning, departing its assembly building — known by the Russian acronym MIK — and arriving at the remote launch pad about a half-hour later.

The Soyuz booster is lifted vertical Tuesday. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon
The Soyuz booster is lifted vertical Tuesday. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon

Hydraulic pistons raised the rocket vertical on its launch mount, and the facility’s 53-meter (174-foot) mobile gantry wheeled into place around the Soyuz booster. The mobile service tower is equipped with cranes that hoisted the Sentinel 1B satellite and its co-passengers on top of the rocket later in the day.

The Sentinel 1B radar imaging spacecraft is joined by France’s Microscope satellite, which will test the physics of free fall with 100 times more precision than possible on Earth. Scientists will monitor the motion of two test masses inside the Microscope satellite in a test of the equivalence principle, a concept first proposed by Galileo and now a key tenet of Einstein’s theory of general relativity, which states that objects fall the same way in vacuum.

Three CubeSats developed by university students in Belgium, Italy and Denmark are also stowed inside the Soyuz rocket’s payload fairing. They were selected from proposals submitted to the European Space Agency’s education-oriented “Fly Your Satellite!” program.

Friday’s launch will be the 14th flight of a Soyuz rocket from French Guiana, and Arianespace’s third launch of the year.

Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon
Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon

The launch profile for Friday’s multi-payload mission is more complex than usual.

The Soyuz rocket will deliver the Fregat upper stage and the mission’s satellite payloads on an initial suborbital trajectory less than nine minutes after liftoff Friday.

The Fregat main engine will ignite four times, first to place Sentinel 1B into its intended 686-kilometer-high (426-mile) orbit at an inclination of 98.18 degrees at T+plus 23 minutes, 35 seconds.

A second ignition of the Fregat engine will put the rocket into an elliptical orbit ranging in altitude from 453 kilometers (281 miles) to 665 kilometers (413 miles) to deploy the three CubeSats at T+plus 2 hours, 48 minutes, 11 seconds.

Two more firings of the upper stage engine will lead to separation of Microscope at T+plus 4 hours, 52 seconds in an orbit 711 kilometers (441 miles) above Earth inclined 98.23 degrees to the equator.

The photos below chronicle the final stages of the launch campaign.

The Sentinel 1B satellite (right) is lifted atop the Fregat upper stage and the French Microscope scientific payload already attached in the lower position of the Soyuz dual-payload adapter. Credit: ESA–Manuel Pedoussaut, 2016
The Sentinel 1B satellite (right) is lifted atop the Fregat upper stage and the French Microscope scientific payload already attached in the lower position of the Soyuz dual-payload adapter. Credit: ESA–Manuel Pedoussaut, 2016
The Sentinel 1B satellite is pictured on top of the Fregat upper stage and the mission's multi-payload stack. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
The Sentinel 1B satellite is pictured on top of the Fregat upper stage and the mission’s multi-payload stack. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
The first half of the Soyuz rocket's payload fairing goes around Sentinel 1B and its co-passengers. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
The first half of the Soyuz rocket’s payload fairing goes around Sentinel 1B and its co-passengers. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
The second half of the clamshell-like fairing encloses the Soyuz rocket's payloads and Fregat upper stage. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
The second half of the clamshell-like fairing encloses the Soyuz rocket’s payloads and Fregat upper stage. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – JM Guillon
The Soyuz payload fairing is complete with the mission logos. Credit: ESA–Manuel Pedoussaut, 2016
The Soyuz payload fairing is complete with the mission logos. Credit: ESA–Manuel Pedoussaut, 2016
The Soyuz payload shroud is moved onto a transporter for the drive to the launch pad. Credit: ESA–Manuel Pedoussaut, 2016
The Soyuz payload shroud is moved onto a transporter for the drive to the launch pad. Credit: ESA–Manuel Pedoussaut, 2016
Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon
Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon
The Soyuz payload composite and Fregat upper stage were transported across the Guiana Space Center on Tuesday for attachment to the rocket. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon
The Soyuz payload composite and Fregat upper stage were transported across the Guiana Space Center on Tuesday for attachment to the rocket. Credit: ESA/CNES/Arianespace – Photo Optique Video du CSG – P. Baudon
The payload composite is lifted into the Soyuz launch pad's mobile gantry Tuesday afternoon. Credit: ESA–Manuel Pedoussaut, 2016
The payload composite is lifted into the Soyuz launch pad’s mobile gantry Tuesday afternoon. Credit: ESA–Manuel Pedoussaut, 2016
The payloads are mated to the Soyuz rocket's third stage inside the launch pad mobile gantry. Credit: ESA–Manuel Pedoussaut, 2016
The payloads are mated to the Soyuz rocket’s third stage inside the launch pad mobile gantry. Credit: ESA–Manuel Pedoussaut, 2016

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