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Recent News

This page contains all recent ILRS news. For those interested in news specific to satellite missions, please visit our Mission News page.

Tom ClarkThe passing of Thomas ClarkRelease Date: 10/05/2021 Space Geodesy lost a longtime colleague and friend with the passing of Thomas Arvid Clark on September 28, 2021. Tom was a pioneer in Space Geodesy and Very Long Baseline Interferometry (VLBI), and a founding member of the NASA Crustal Dynamics Project.

Tom received his B.S. in Engineering Physics and his Ph.D. in Astro-Geophysics from the University of Colorado in 1961 and 1967 respectively. From 1966 to 1968, he served as Chief of the Astronomy Branch at NASA Marshall Space Flight Center and as Project Scientist on the Spacelab Coronagraph. At GSFC, where he moved in 1968, Tom received numerous NASA awards for his pioneering work on Radio Astronomy Explorer 1 and 2 and several generations of Very Long Baseline Interferometry systems. Tom developed the Totally Accurate Clock (TAC), an inexpensive GPS timing receiver that found widespread use in a number of global networks. Tom was named a Fellow of the American Geophysical Union (AGU) in 1991 and a Fellow of the International Association of Geodesy (IAG) in 1999. Tom was also a pioneer in amateur and digital radio; he designed and flew several low cost satellites for relaying amateur radio messages around the globe and is a past president of AMSAT. He was one of only 50 initial inductees into the CQ Amateur Radio Hall of Fame, a list which included such engineering luminaries and inventors as Guglielmo Marconi (radio), Samuel Morse (telegraph), Nikola Tesla (HF generators and radio), and John Bardeen and William Schockley (transistor). Tom retired from GSFC in 2001 but remained active in Amateur Radio activities.

Those of us who worked with Tom during the Crustal Dynamics period remember him as a brilliant mind, a very interesting and sometimes caustic character, but someone who was kind, supportive, and very helpful to those of us around him. We will miss him.

ILRS logoThird circular for ILRS Virtual World Tour 2021 releasedRelease Date: 09/30/2021 Dear Colleagues:

We look forward to seeing you at "ILRS Virtual World Tour 2021". Progress has been made at the five tour hosts and by the session chairs. Now we have just opened the registration form. Please visit the event website below and find the link.
Registration period: October 1 to 15, 2021

Participants are encouraged to register as a group if possible, due to the limit of Microsoft Teams individual participants allowed. The URL links will be sent only to the registered people.

See you in a month!

ILRS Virtual World Tour 2021 Organizers:
Claudia Carabajal/SSAI, Inc, NASA Goddard Space Flight Center, USA
Evan Hoffman/NASA Goddard Space Flight Center, USA
Igor Ignatenko/VNIIFTRI, Russia
Jason Laing/Peraton NSGN Operations Lead, USA
Toshimichi Otsubo/Hitotsubashi University, Japan (Chair)
Michael Pearlman/ Harvard-Smithsonian Center for Astrophysics, USA
Ulrich Schreiber/Geodetic Observatory Wettzell, Germany
Zhang Zhongping/Shanghai Astronomical Observatory, China

ILRS logoSecond circular for ILRS Virtual World Tour 2021 releasedRelease Date: 08/31/2021 Dear Colleagues:

We are happy to report the updates on this year's "ILRS Virtual World Tour". In addition to the virtual visits to the stations (∼120 min), short special add-on sessions (30-60 min) are planned with the help of the Standing Committee Chairs. We look forward to seeing you in the last week of October.

Schedule (tentative; in UTC):

Monday, October 25
12:00 Opening session with reports from ILRS CB and Geodetic Community
12:45 Virtual Tour of Herstmonceux, UK

Tuesday, October 26
13:00 Virtual Tour of Wettzell, Germany
15:00 Special Session on Network & Engineering, LLR and Space Debris Ranging

Wednesday, October 27
13:00 Virtual Tour of Mendeleevo, Russia
15:00 Special Session on Analysis

Thursday, October 28
06:00 Virtual Tour of Shanghai, China
08:00 Special Session on Missions (1)

Friday, October 29
16:00 Virtual Tour of Monument Peak, USA
18:00 Special Session on Data Format and Missions (2), and Closing

Workshop website: https://ilrs.gsfc.nasa.gov/ILRS_Virtual_World_Tour_2021/index.html

Microsoft Teams will be used for all of these sessions.
The Third Circular will be issued later with details on registration.

ILRS Virtual World Tour 2021 Organizers:
Claudia Carabajal/SSAI, Inc @ NASA Goddard Space Flight Center, USA
Evan Hoffman/NASA Goddard Space Flight Center, USA
Igor Ignatenko/VNIIFTRI, Russia
Jason Laing/Peraton NSGN Operations Lead, USA
Toshimichi Otsubo/Hitotsubashi University, Japan (Chair)
Michael Pearlman/Center for Astrophysics, USA
Ulrich Schreiber/Geodetic Observatory Wettzell, Germany
Zhang Zhongping/Shanghai Astronomical Observatory, China

ILRS logoThe Passing of Prof. Vladimir VasilievRelease Date: 08/11/2021 Prof. Vladimir Vasiliev, a Russian scientist who made a huge personal contribution to the development of radio-laser systems, died on August 10, 2021 from coronavirus at the age of 90. In 1962, on his initiative, work began to assess the possibilities of using lasers in space technology. Vasiliev is the ancestor and ideologist of domestic optical-laser topics in such areas as precision geodetic; radio and optical range finders; onboard laser range finders for space systems; laser gyroscopes; spacecraft docking systems; optical communication; and navigation systems. Under his leadership, the necessary design and technological base was formed for the creation of on-board and ground laser information-measuring systems for various purposes, Vasiliev's ideas for calculating high-performance optical retroreflective antennas have been successfully used in the creation of the global GLONASS system and in many other domestic and international satellite laser ranging systems.

Vasiliev is the ideologist of the creation of passive precision optical mini-satellites operating on the principle of the Luneberg lens. These laser passive mini-satellites open up the possibility of studying geodeformations with a sub-millimeter accuracy. In 2002, an experimental model of the retroreflector ball was manufactured, installed on the Meteor-3M spacecraft and successfully passed flight tests. In 2009, the world's first full-scale autonomous glass laser mini-satellite BLITS was launched and successfully operated together with the global network of ILRS laser stations. As a result of many years of fruitful scientific and pedagogical activity, V. Vasiliev created a well known scientific school, which enjoys the well-deserved authority of specialists in our country and abroad. V. Vasiliev has been awarded many state and departmental awards.

He is the author of over 250 scientific works and 6 monographs, one of which is "Electro-optical and radio measurements", adopted as a textbook for higher educational institutions.

The passing of Vladimir Vasiliev is a great loss to all of us. We send our condolences to Professor Vasiliev's family.

ILRS logoNew schedule of ILRS Workshop Kunming on Laser RangingRelease Date: 08/10/2021 Dear Colleagues:

After discussion with our local colleagues in Kunming, the new date of the 22nd International Workshop on Laser Ranging has now been decided to be October 31 - November 4, 2022.

In view of the covid pandemic, further announcements will be updated ASAP. You can also find new information at: 22ndilrs2020.csp.escience.cn

Logo for 2021 ILRS Virtual World TourILRS Virtual World Tour 2021- October 25-29, 2021Release Date: 07/22/2021 Dear Colleagues,

Due to the COVID 19, we have had to postpone our laser workshops, our annual seminal events, in 2020 and 2021. The ILRS again wishes to provide the opportunity for our worldwide community to meet, at least virtually, and share. We are now planning the "2021" version of "Virtual World Tour" following the success of last year.

This online event will be held October 25-29, 2021, to virtually visit 5 stations in 5 days, stopping at: Herstmonceux, UK, Mendeleevo, Russia, Monument Peak, USA, Shanghai, China and Wettzell, Germany.

The time table details are now in process. We are also planning short add-on session each dayto allow us to provide updates and some opportunity for discussion on issues important to the ILRS community.

Please highlight the dates on your calendar. More details will follow.

Dan O'Gara retired after 37 years of dedicated support to the International Geodetic Community Release Date: 05/12/2021 The International Laser Ranging Service (ILRS) and the NASA Space Geodesy Project (SGP) express our appreciation and congratulations to Dan O'Gara for his 37 years of service to the international geodetic community. Dan retired from the University of Hawaii (UH) on April 30, 2021.

Much of Dan O'Gara's work at UH was with the Lunar Ranging Experiment (LURE) observatory. The University of Hawaii's LURE was installed on Haleakala in 1973. Dan joined the team in the early 1980s, performing maintenance and developing the software to control the LURE beam director and operating the system. The station became known as HOLLAS by the ILRS community as it gained the capability to track satellites and took on the 4-character code of HALL (for Haleakala Laser), but the locals always referred to it as LURE. Dan eventually became the station manager for LURE while he continued to develop the software and operate the system.

See https://ilrs.gsfc.nasa.gov/network/stations/inactive/HALL_station_info.html and http://koa.ifa.hawaii.edu/Lure/#:~:text=The%20Lure%20Observatory%20is%20located,Maui%20in%20the%20Hawaiian%20archipelago.&text=The%20Lunar%20Ranging%20Experiment%20(LURE,and%20reflectors%20on%20the%20Moon

The LURE facility was decommissioned in 1990 to make room for another experiment. In 2006, NASA installed the TLRS-4 Satellite Laser Ranging station at a different location on the top of the mountain. Dan continued his work as station manager, operator, and laser ranging software expert for TLRS-4.

Dan is well known and liked by everyone in the ILRS and SGP. He continued his interest in the lunar community even after the UH lunar laser ranging program ended. He participated in multiple ILRS Workshops including the Workshop in Annapolis which celebrated the 50th anniversary of SLR. He hosted numerous site visits to Haleakala by many groups and supported the Space Geodesy Project's preliminary work to deploy a next generation SLR station and new GNSS stations on the top of Haleakala, helping the SGP team find a good location for the new SLR system and supporting the team's site visit in 2015.

The Maui SLR stations have played a critical role in the international SLR network by covering satellite tracking over the Pacific. The station team under the leadership and management of Dan O'Gara has done a great job. His calm demeanor and sense of humor has been much appreciated.

Dan was the face of Hawaii laser ranging for many decades. He will be greatly missed by his colleagues and friends in the Space Geodesy Project and the International Laser Ranging Service. We wish Dan a healthy and happy retirement, and great success in his future plans!

group photo with Dan O'Gara in the center

Dan O'Gara, featured at the center of the picture, accompanied by SGP folks during a site visit in 2015. From left to right: Jan McGarry, Stephen Merkowitz, Dan O'Gara, Jim Long, Scott Wetzel, and David Stowers. (Photo credit: Scott Wetzel)

ILRS logoILRS Workshops Cancelled/Postponed Release Date: 04/09/2021 Dear Colleagues,

In view of the continued threat of the current pandemic, the ILRS and the members of the Kunmimg Station have decided that it would be best to postpone the 22nd International Workshop on Laser Ranging until 2022. We know that it is a disappointment to skip another year, but we really have no choice. The date for the 2022 workshop at Kunming, China has yet to be decided.

Plans are being formulated to have another program of virtual station tours, with perhaps some talks on pertinent ILRS subjects in late 2021, in place of the workshop.

As a consequence, the Technical Workshop scheduled for Arequipa, Peru will also be postponed another year, until 2023.

We thank both the Kunming and Arequipa teams for their patience and preparation to date. We know that both workshops will be great successes.

Looking on the bright side, our community should have much to report when these workshops are finally held.

We hope that you and your community will continue to act in safety.

With best wishes,

Mike Pearlman
Director, ILRS Central Bureau

ILRS logoNew Software for ILRS Station Plots Release Date: 02/05/2021 The ILRS has been generating global report cards monthly including meteorological data, LAGEOS performance, and satellite data information. The software to create these plots have been recently upgraded through the efforts of the Station Plots Working Group, formulated by the ILRS Central Bureau in 2020. The start date of the new charts begin in 2012/05, when the CRD format was released.

With this upgrade, some plots were combined and additions were made. For more information on the changes made to the report cards, please see: With this upgrade, some plots were combined and additions were made. For more information on the changes made to the report cards, please see the Overview of Station Plots page.

If you notice any discrepancies on a webpage please feel free to contact us at support-cddis@earthdata.nasa.gov.

Hayabusa2 logoTwo-way ranging to the Hayabusa 2 spacecraft is succesfulRelease Date: 02/05/2021 In JAXA's press conference on 4 Feb 2021, Prof Takahide Mizuno of JAXA and Prof Toshimichi Otsubo of Hitotsubashi University announced the success of two-way ranging to the Hayabusa 2 spacecraft. During the post-flyby period in December 2020, a two-way link was established with Grasse, and one-way links were confirmed with Koganei and Mt Stromlo.

Read the results of the experiment...

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