A2 – Commission A2 Rotation of the Earth


Earth rotation is an interdisciplinary topic that bridges astronomy and geodesy. Precise knowledge of the Earth's rotation and its variations is needed for positioning and navigating objects on Earth and in space. And the analysis of Earth rotation variations provides important information about interactions between the various components of the Earth system and about global change phenomena.

The objectives of Commission A2 on Rotation of the Earth are to:

  1. Encourage and develop cooperation and collaboration in observation and theoretical studies of Earth orientation variations (the motions of the pole in the terrestrial and celestial reference systems and rotation about the pole).
  2. Serve the astronomical community by linking it to the official organizations that provide the International Terrestrial and Celestial Reference Systems/Frames (ITRS/ITRF and ICRS/ICRF) and Earth orientation parameters (EOP): International Association of Geodesy (IAG), International Earth Rotation and Reference Systems Service (IERS), International VLBI Service for Geodesy and Astrometry (IVS), International GNSS Service (IGS), International Laser Ranging Service (ILRS), International DORIS Service (IDS).
  3. Develop methods for improving the accuracy and understanding of Earth orientation variations and related reference systems/frames.
  4. Ensure agreement and continuity of the reference frames used for studying Earth orientation variations with other astronomical reference frames and their densification.
  5. Provide means of comparing observational and analysis methods and results to ensure accuracy of data and models and encourage the development of new observation techniques.

The Commission meets its objectives by fostering research and discussion on Earth rotation and reference frames, by organizing topical symposia and workshops, and by forming relevant Working Groups.

Commission Web Page

Commission Members (111)

Under Division

Division A Fundamental Astronomy

Commission Working Groups

Commission A2 WG Consistent Realization of TRF, CRF and EOP
Commission A2 WG Improving Theories and Models of the Earth’s Rotation (ITMER)

Florian Seitz

Technische Universität München
Deutsches Geodätisches Forschungsinstitut (DGFI)
Arcisstr. 21
D-80333 Munich

Phone: +49 89 23031 1106
Email: florianseitztumde
Organization website: http://www.dgfi.tum.de

NCA adherence: Germany

Last updated:
April 16, 2020

Zinovy M. Malkin

Pulkovo Observatory RAS
Radioastronomy Researches Department
Pulkovskoe Shosse 65
196140 St Petersburg
Russian Federation

Phone: +7 812 363 7442
Email 1: malkingaoranru
Email 2: zmalkinzmalkincom
Personal website: http://www.zmalkin.com/
Organization website: http://www.gaoran.ru/

NCA adherence: Russian Federation

Last updated:
April 16, 2020

Alberto Escapa

Universidad de Alicante/Universidad de León

Email: albertoescapauaes

NCA adherence: Spain

Last updated:
September 17, 2020

Richard Gross

Jet Propulsion Laboratory
Geodynamics and Space Geodesy Group
Mail Stop 238-600
4800 Oak Grove Drive
Pasadena, CA 91109
California (CA)
United States

Phone: +1 818 354 4010
Email 1: RichardGrossjplnasagov
Email 2: richardsgrossjplnasagov
Organization website: http://www.jpl.nasa.gov/index.cfm

NCA adherence: United States

Last updated:
July 27, 2020

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