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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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LAGEOS (LAser GEOdynamics Satellite-1) (Courtesy NASA)

Highlights

The 23rd International Workshop on Laser Ranging, Kunming - China, Oct.20th–26th, 2024 – Second Announcement (updated with a change in venue)Release Date: 06/12/2024 The Yunnan Observatories and the International Laser Ranging Service (ILRS) have released an update to the Second Announcement for the 23rd International Workshop on Laser Ranging in Kunming, China. The workshop will be held at the Zhongwei Green Lake Hotel Kunming, near one of the most popular attractions in Kunming, the Green Lake Park.

Hotel info: http://www.zhongweigreenlake.cn/en

Reservation can be accessed through the workshop website.

The announcement can be found here.

The 23rd International Workshop on Laser Ranging, Kunming - China, Oct.20th–26th, 2024 Release Date: 03/11/2024 The Yunnan Observatories and the International Laser Ranging Service (ILRS) are pleased to announce that the 23rd International Workshop on Laser Ranging will be held in Kunming, China during 20-26 October 2024.

More details can be found in the workshop website online with the link below:

https://23rdworkshop.casconf.cn/

We look forward to your participation!

The SLR-tailored version of ITRF2020, the SLRF2020, has been released to the publicRelease Date: 07/25/2023 The long-awaited SLR-tailored version of ITRF2020, the SLRF2020, has been released to the public, along with the associated Data Handling File required for proper and accurate reduction of SLR data. Both files contain notes that are important to users, especially to those requiring the highest quality results in their work; it is imperative that users read these notes before implementing the new TRF in their production lines.

The two files can be accessed from the ILRS website pages:

https://ilrs.gsfc.nasa.gov/science/dataAnalysisResources/index.html
https://ilrs.gsfc.nasa.gov/network/site_information/index.html

CDDIS Landing pages with the appropriate DOIs are here:

https://cddis.nasa.gov/Data_and_Derived_Products/SLR/slrf_2020.html
https://cddis.nasa.gov/Data_and_Derived_Products/SLR/slrf_2020_DHF.html

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

GGOS releases short film highlighting the Terrestrial Reference Frame - The GGOS (Global Geodetic Observing System) Coordinating Office has now released a new 2.5-minute short film highlighting the critical role of geodetic terrestrial reference frames. This video is primarily aimed at the general public and has been produced in collaboration with the UN-GGCE (United Nations Global Geodetic Center of Excellence). The video is available with subtitles in over 16 languages and can be viewed on the GGOS YouTube channel:
https://www.youtube.com/watch?v=zfqq-0d2txk

This short video complements the more comprehensive 10-minute version (https://www.youtube.com/watch?v=vvNXv05646M), available in multiple languages, which has been viewed over 40,000 times since its release in September 2023.

On behalf of GGOS, the ILRS kindly invites ILRS community members to share this video with colleagues in their institutes, universities and the general public.

Please send comments or feedback concerning these videos to the ILRS central bureau or to Martin Sehnal at the GGOS Coordinating Office (Federal Office of Metrology and Surveying, BEV, Austria).

The 23rd International Workshop on Laser Ranging, Kunming - China, Oct.20th–26th, 2024 – Second Announcement (updated with a change in venue) - The Yunnan Observatories and the International Laser Ranging Service (ILRS) have released an update to the Second Announcement for the 23rd International Workshop on Laser Raning in Kunming, China. The workshop will be held at the Zhongwei Green Lake Hotel Kunming, near one of the most popular attractions in Kunming, the Green Lake Park.

Hotel info: http://www.zhongweigreenlake.cn/en

Reservation can be accessed through the workshop website.

The full updated announcement can be found here.

National Geodetic Survey (NGS) 2024 Local Tie Survey for Greenbelt is now available - The National Geodetic Survey (NGS) has posted the results of their recent local tie survey at the Goddard Geophysical and Astronomical Observatory (GGAO) in Greenbelt, Maryland, U.S.A. The GGAO hosts all four space geodetic techniques, including SLR, VLBI, GNSS & DORIS. The local tie survey took place from March 25 to April 5, 2024, and the NGS team was led by Kevin Jordan of the NGS Field Operations Branch.

The survey results, report, and SINEX file are available at the NOAA/NGS website in the Table by clicking on the links for "Washington (2024)". Please contact the National Geodetic Survey (NGS) and/or the ILRS Central Bureau with any questions or feedback.

URL: https://www.ngs.noaa.gov/corbin/iss/index.shtml