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Overview

Satellite Laser Ranging (SLR) and Lunar Laser Ranging (LLR) use short-pulse lasers and state-of-the-art optical receivers and timing electronics to measure the two-way time of flight (and hence distance) from ground stations to retroreflector arrays on Earth orbiting satellites and the Moon. Scientific products derived using SLR and LLR data include precise geocentric positions and motions of ground stations, satellite orbits, components of Earth’s gravity field and their temporal variations, Earth Orientation Parameters (EOP), precise lunar ephemerides and information about the internal structure of the Moon. Laser ranging systems are already measuring the one-way distance to remote optical receivers in space and can perform very accurate time transfer between sites far apart. Laser ranging activities are organized under the International Laser Ranging Service (ILRS) which provides global satellite and lunar laser ranging data and their derived data products to support research in geodesy, geophysics, Lunar science, and fundamental constants. This includes data products that are fundamental to the International Terrestrial Reference Frame (ITRF), which is established and maintained by the International Earth Rotation and Reference Systems Service (IERS). The ILRS develops the necessary global standards/specifications for laser ranging activities and encourages international adherence to its conventions.

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Highlights

First Lunar Laser Ranging (LLR) Meeting, September 14^th and 15^th, 2023, Pole Astronomie Géoazur, Observatoire de la Côte d'Azur (OCA), CNRS - INSU, Université Côte d'Azur (UCA), France Release Date: 05/10/2023 The first LLR meeting wishes to bring both the producers, the users and the science behind lunar laser ranging together in order to join efforts and resources, to define goals and enhance the visibility for a LLR community, and to identify synergies and to plan for the future. The goal is to encourage every group to help and form a visible global community.

Clément Courde
courde@geoazur.unice.fr

Julien Chabé
chabe@geoazur.unice.fr

SLR & DORIS Support the Discovery of 19,000 Undersea Volcanos Using Satellite AltimetryRelease Date: 04/21/2023

A team of scientists has published a new catalog of undersea volcanos, or seamounts, that are derived using ocean radar altimetry data from the satellites Jason-1, Envisat CryoSat-2, and Saral/AltiKa. The altimeter data for this study were obtained primarily from the geodetic missions for these satellites. In the geodetic missions, the satellites flew so that successive ground tracks were aligned close together. This facilitated the mapping of the ocean geoid.The data from these most recent satellite missions have improved the ability to find previously undetected seamounts, from how the mass of the seamounts perturbs the shape of the ocean surface.

The new map will aid studies of marine tectonics, geology, ecology and ocean mixing.

This discovery was supported by Precise Orbit Determination (POD), including Satellite Laser Ranging (SLR), and DORIS for Jason-1, Envisat, CryoSat-2, and Saral/ALtiKa whose altimeter data contributed to the results of this new study.

More information:
Overview article in Science magazine, April 19, 2023:
https://www.science.org/content/article/it-s-just-mind-boggling-more-19-000-undersea-volcanoes-discovered

Scientific publication, published March 20, 2023:
Gevorgian J., Sandwell D., Yu Y., Kim S.-S. and Wessel P. (2023). "Global distribution and morphology of small seamounts". Earth and Space Science, 10, e2022EA002331.
https://doi.org/10.1029/2022EA002331

22^nd International Workshop on Laser Ranging (IWLR) in Guadalajara, Spain - November 7-11, 2022 - Session Videos Available for viewingRelease Date: 03/03/2023

We are pleased to announce that the recordings for the 22^nd International Workshop on Laser Ranging (IWLR) held in Guadalajara, Spain, are available for viewing. This is the first time that a full ILRS workshop is made available in video. This, together with the ILRS Virtual World Tours 2020 and 2021, all the events organized by the ILRS in the last three years are publicly accessible to everyone.

The 22^nd IWLR was organized by the Observatory of Yebes, the National Geographic Institute of Spain (IGN/CNIG), and the ILRS. Over 170 delegates from 20 different countries participated in the conference, which took place on 7–11 November 2022. With the theme "Reconnecting the ILRS community", this event was for the first time in a hybrid in person/online format. The conference was a great opportunity for the experts in the various SLR-related fields to meet, discuss, and exchange ideas and new developments.

The video recordings of the conference include the talks from all the 10 Main Sessions; the presentations kindly given by the invited speakers; and the meetings of the ILRS Standing Committees on Data Formats & Proceedings, Networks & Engineering, and Missions. The Opening and Closing sessions, including the SLR Pioneers Awards, are all available for viewing as well.

You can access the recording here: https://www.youtube.com/@22ndIWLR

We thank the Local Organizing Committee for making and sharing the recordings of the conference possible.

Updated list of Conferences and workshops related to earth rotation, reference frames, geophysical fluids, GNSS, SLR, VLBI, DORIS, etc. posted by the IERS

More news...

Recent News

First Lunar Laser Ranging (LLR) Meeting, September 14^th and 15^th, 2023, Pole Astronomie Géoazur, Observatoire de la Côte d'Azur (OCA), CNRS - INSU, Université Côte d'Azur (UCA), France - The first LLR meeting wishes to bring both the producers, the users and the science behind lunar laser ranging together in order to join efforts and resources, to define goals and enhance the visibility for a LLR community, and to identify synergies and to plan for the future. The goal is to encourage every group to help and form a visible global community.

Clément Courde
courde@geoazur.unice.fr

Julien Chabé
chabe@geoazur.unice.fr

SLR & DORIS Support the Discovery of 19,000 Undersea Volcanos Using Satellite Altimetry - A team of scientists has published a new catalog of undersea volcanos, or seamounts, that are derived using ocean radar altimetry data from the satellites Jason-1, Envisat CryoSat-2, and Saral/AltiKa. The altimeter data for this study were obtained primarily from the geodetic missions for these satellites. In the geodetic missions, the satellites flew so that successive ground tracks were aligned close together. This facilitated the mapping of the ocean geoid.The data from these most recent satellite missions have improved the ability to find previously undetected seamounts, from how the mass of the seamounts perturbs the shape of the ocean surface.

The new map will aid studies of marine tectonics, geology, ecology and ocean mixing.

This discovery was supported by Precise Orbit Determination (POD), including Satellite Laser Ranging (SLR), and DORIS for Jason-1, Envisat, CryoSat-2, and Saral/ALtiKa whose altimeter data contributed to the results of this new study.

Read more...

Opening ceremony held at the SLR Station in Tsukuba, Japan (ID: 7306, Code: TKBL) - Shinichi Nakamura, the manager of the new JAXA Tsukuba SLR station reports that the development phase has been completed. The new SLR station is located in Tsukuba, southern Ibaraki Prefecture, about 50 km from central Tokyo. JAXA held the opening ceremony of the station on March 30, 2023. A total of 36 people attended the ceremony, including representatives of the Japanese Coast Guard, Hitotsubashi University, the University of Tokyo, the JAXA director, and many JAXA satellite project managers. Dr. Stephen Merkowitz, Chair of the ILRS Governing Board, gave a congratulatory speech on the opening of the station, which added to the festivities. With the guidance of the ILRS, the SLR Tsukuba station was assigned the station ID: 7306, and Code: TKBL. The JAXA Tsukuba station staff are proud that the new station will be a member of the ILRS network and look forward to contributing to space development and science through SLR operations. In April, 2023, trial operation will be held to familiarize JAXA staff and full operation is scheduled to start in May 2023.

The ILRS congratulates the JAXA team on the commissioning of this new SLR station.

See photos...

Meetings

FIG Working Week 2023, Orlando, FL, USA, May 28 - June 1, 2023

European Navigation Conference 2023 (ENC 2023), Noordwijk, The Netherlands, May 31 - June 2, 2023

26th EVGA Working Meeting, Koetzting, Bavaria, Germany, June 11-15, 2023

Publications

2016-2019 ILRS Report

Proceedings from the 19th International Workshop on Laser Ranging

International Laser Ranging Service

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