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G4S_2.0 (Galileo for Science): Motivations for an SLR Campaign


G4S_2.0 in a nutshell

The G4S_2.0 project, funded by the Italian Space Agency (ASI), aims to perform a set of measurements in the field of gravitation with the Galileo satellites of the Full Operational Capability (FOC) constellation, taking advantage of the accuracy of the on-board atomic clocks and, in particular, of GSAT0201 and GSAT0202 by exploiting their relatively high eccentricity (≅0.16).

Research Institutes Involved:


Main goals of the G4S_2.0 project:

  • A new measurement of gravitational red shift
  • A measurement of relativistic precessions on the two satellites in eccentric orbit
  • Constraints on Dark Matter in the Milky Way
  • Relativistic Positioning System
  • Development of new models for non-gravitational forces
  • Development of a new accelerometer concept for a next generation of Galileo satellites

Each week, the ILRS we will post the statistics for the previous week and the aggregate statistics for the campaign since it started.

Refer to the Project furnished SLR Campaign Website to see how the network is doing and which satellites need tracking help. Coverage is very important here, so whatever you can do will help make this campaign a success. We encourage every station to participate at whatever level they can.

The link for the G4S_2.0 experiment website Galileo For Science 2.0 is here.

Plan

The project requests that the ILRS Network average at least 10 Normal Points (NPs) per satellite per day. There are approximately 22 satellites in the Campaign. We suggest that stations try to take 3 - 5 NP’s on as many of the Galileo satellites as they can each day. The next day, try other satellites. Refer to the Project furnished SLR Campaign Website to see how the network is doing and which satellites need tracking help. Coverage is very important here, so whatever you can do will help make this campaign a success.

The Galileo for Science project is analyzing all the data collected from the beginning of the campaign from January 20th through April 30th, 2024.

The next phase of the campaign will start on May 1st, 2024.

Tracking will focus on the two Galileo satellites with elliptical orbits, Galileo 201 and 202. The other satellites' tracking should follow the posted priorities.

We anticipate that other changes will made later on during the campaign.

Your participation is still very important to the Galileo campaign and to those still using the full Galileo constellation.

We encourage every station to participate at whatever level they can. Don’t just sit by and watch others.

Thank you for your participation,

The G4S_2.0 project and the ILRS Central Bureau

Galileo for Science (G4S) Tracking Campaign - Weekly and Aggregate Reports

Reports Provided by the ILRS CB (Van Husson, Peraton)

Weekly and Aggregate Tracking
Normal Points (NP) Totals and Total Passes

01/24/2024 02/08/2024 02/14/2024 02/21/2024 02/28/2024
03/06/2024 03/13/2024 03/20/2024 03/27/2024 04/03/2024
04/10/2024 04/17/2024 04/24/2024 05/01/2024 05/08/2024
05/15/2024 05/22/2024 05/29/2024 06/05/2024 06/12/2024
06/19/2024 06/26/2024 07/03/2024 07/10/2024 07/17/2024
07/24/2024 07/31/2024 08/07/2024 08/14/2024 08/21/2024
08/28/2024 09/04/2024 09/11/2024 09/18/2024 10/02/2024
10/09/2024 10/16/2024 10/23/2024 10/30/2024 11/06/2024
11/13/2024 11/20/2024 11/26/2024 12/04/2024 12/11/2024
12/18/2024 12/25/2024 01/01/2025