ILRS Home Page

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.

Quick Links

Welcome

NGSLR Greenbelt, MD

Highlights

Second Circular for the 21st International Workshop on Laser Ranging ReleasedRelease Date: 06/06/2018The Space Environment Research Centre (SERC) and the International Laser Ranging Service (ILRS) are actively organizing the 21st International Workshop on Laser Ranging in Canberra, Australia during the week of November 05-09, 2018. The second circular has been released. Registration is now open and attendees are encouraged to submit an abstract for oral and poster sessions.

First LARGE Campaign of 2018 is Now OverRelease Date: 05/29/2018The first 2018 LARGE Campaign is now over. A summary report for the campaign is available on the LARGE Activities and Meetings page.

EOSDIS awarded the 2015 Pecora awardRelease Date: 02/14/2018EOSDIS was awarded the 2015 Pecora award. This prestigious award is given to groups that make outstanding contributions toward understanding the Earth by means of remote sensing. The citation highlights the EOSDIS accomplishments in providing an open archive system for a global user community. CDDIS is one of twelve DAACs supporting EOSDIS efforts through the Earth Science Data and Information System (ESDIS) project. Carey Noll, CDDIS Manager, accepted their award certificate from Andy Mitchell, ESDIS Project Manager, and Jeanne Behnke, Deputy Project Manager/Operations, at the 2018 DAAC Managers Meeting.

First Circular for the 21st International Workshop on Laser Ranging ReleasedRelease Date: 02/02/2018The Space Environment Research Centre (SERC) and the International Laser Ranging Service (ILRS) are pleased to announce that the 21st International Workshop on Laser Ranging will be held in Canberra, Australia during the week of November 04-09, 2018 at the John Curtin School of Medical Research (Australian National University) and Mount Stromlo. The first circular has been released.

ILRS Approves New Network Application Form and PolicyRelease Date: 06/14/2017The ILRS has approved a new policy and application form for new stations to join the ILRS network.

More news...

Recent News

JCET weather service for ILRS network - JCET's ILRS ASC Product and Information Server now includes a link to an ILRS network weather forecast service, compiled from The Weather Underground.

Second Circular for the 21st International Workshop on Laser Ranging Released - The Space Environment Research Centre (SERC) and the International Laser Ranging Service (ILRS) are actively organizing the 21st International Workshop on Laser Ranging in Canberra, Australia during the week of November 05-09, 2018. The second circular has been released. Registration is now open and attendees are encouraged to submit an abstract for oral and poster sessions.

First successful SLR returns to S-Net - The SLR system in Riga, Latvia was the first ILRS station to obtain returns from one of the four SNET satellites (SNET-4); Yarragadee, Australia also tracked SNET-4 the following day. Riga obtained returns at 21:57 UTC on April 12; Yarragadee's first successful pass was on April 13 at 16:00 UTC. Congratulations to both stations on their persistent efforts to range to these difficult targets.

Time Transfer by Laser Link (T2L2) mission onboard the Jason-2 satellite is now completed - The Time Transfer by Laser Link (T2L2) mission onboard the Jason-2 satellite is now completed. The T2L2 space instrument, which has been in operation for nearly 10 years, will be turned off on April 09, 2018. Most of the initial objectives for the experiment have been successfully achieved. The Jason-2 satellite remains operational, as does laser ranging to the satellite.