NASA Logo in the header
Sciences and Exploration Directorate

John M Gipson

(CHIEF SCIENTIST)

John M Gipson's Contact Card & Information.
Email: john.m.gipson@nasa.gov
Phone: 301.614.6876
Org Code: 61A
Address:
NASA/GSFC
 Mail Code 61A.1
 Greenbelt, MD 20771
Employer: NVI INC

Brief Bio

John Gipson  recieved his PhD in theoretical particle physics from Yale University in 1982. He worked at Virginia Tech as post-doc and Assistant Professor from 1982-1984. 

From 1985 through 1991 he worked at Interferometrics, Inc as a Senior Scienist.  He developed a technique to make holographic measurements of satellite dishes using radio waves. He also developed a technique using interferometry to determine the location of ground based transmitters causing interference with communicatino satellites and was awarded a patent for the system. This system is still in use. 

He has been involved periodically with the Goddard VLBI group since 1986, and in 1990 became a permanent member of the group.  Since 2002 he has been the senior contractor on the support contract that provides VLBI analysis operations support to NASA.  Within VLBI he has a special interest in analysis. 

 

Education

1982 Ph D Theoretical Physics, Yale University

1977 MS  Physics, Yale University

 

Research Interests

Earth Orientation

John Gipson has a special interest in the measurement and modeling of Earth Orientation Parameter (EOP) variation, and is the chair of the IERS working group on the diurnal and semi-diurnal EOP. He is the chapter editor of the EOP chapter in the upcoming IERS conventions.

 

Positions/Employment

President & Project Manager

NVI, Inc - Greenbelt, MD

September 2002 - Present

President of NVI, Inc and Project Manager of VLBI support contract. 

Senior Scientist

NVI, Inc - Greenbelt, MD

September 1991 - September 2002

Senior Scientist on the NVI VLBI support contract. In charge of analysis. 

Senior Scientist

Interferometrics,Inc - Vienna, VA

December 1984 - September 1991

Research and development position.  1.)Developed a system for doing microwave holography on antennas. 2) Developed a system to use interferometry to determine the location of ground based transmitters causing interference with communications satellites; 3) Developed a system for locating lighning strikes using interferometry. Items 2 and 3 received a patent.

Post-Doc/Assistant Professor

Virginia Tech - Blacksburg, VA

July 1982 - November 1984

Post-doc and Assistant Professor in Physics department. 

Professional Service

IVS Analysys Coordinator.  In charge of ensuring the quality and timeliness of IVS products, ans serving as a liason to other techniques.

IVS Directing Board. The IVS Analysis Coordinator is in permanent member of the Directing Board.

IVS Working Group 4 on VLBI Data Structures,Chair.  This working group was tasked with coming up with a data structure and format that would handle current and future VLBI data. The working group designed and tested the vgosDB format which is now the default for geodetic VLBI data. 

IVS Working Group 7 on Satellite Observations. 

IVS Working Group 8 on Galactic Aberration.  The rotation of the solare  system about the galactic center leads to an apparent change in the position of VLBI sources. This effect is called Galactic Aberration, and this working group was set up to make recommendatins on how to model and incorporate this effect in VLBI.  

IERS Working Group (chair)  on sub-diurnal  Earth Orienation Parametger Variation. This working group was established to make recommendations about which EOP model to use in geodetic analysis. It includes representatives of all the techniques. 

Publications

Refereed

2020. "On the organization of CONT17.", Journal of Geodesy, 94 (10): [10.1007/s00190-020-01436-x] [Journal Article/Letter]

2020. "Balancing Source Strength and Sky Coverage in IVS-INT01 Scheduling.", Journal of Geodesy, 94 (18): [10.1007/s00190-020-01343-1] [Journal Article/Letter]

2019. "Modernizing and expanding the NASA Space Geodesy Network to meet future geodetic requirements.", Journal of Geodesy, 93 (11): 2263-2273 [10.1007/s00190-018-1204-5] [Journal Article/Letter]

2019. "Galactocentric acceleration in VLBI analysis.", Astronomy & Astrophysics, 630 A93 [10.1051/0004-6361/201935379] [Journal Article/Letter]

2018. "Demonstration of a Broadband Very Long Baseline Interferometer System: A New Instrument for High-Precision Space Geodesy.", Radio Science, 63 1263-1291 [10.1029/2018rs006617] [Journal Article/Letter]

2016. "Comparison of VieVS and Solve UT1 results from VLBI measurements.", Journal of Geodesy and Geoinformation, 3 (1): 1-8 [Full Text] [Journal Article/Letter]

2016. "Improvement of the IVS-INT01 sessions by source selection: development and evaluation of the maximal source strategy.", J. Geodesy, 90 (3): 287-303 [10.1007/s00190-015-0873-6] [Journal Article/Letter]

2016. "IVS Observation of ICRF2-Gaia Transfer Sources.", The Astronomical Journal, 151 (3): 79 [10.3847/0004-6256/151/3/79] [Journal Article/Letter]

2015. "The Second Realization of the International Celestial Reference Frame by Very Long Baseline Interferometry.", The Astronomical Journal, 150 (2): 58 [10.1088/0004-6256/150/2/58] [Journal Article/Letter]

2014. "Tropospheric delay ray tracing applied in VLBI analysis.", Journal of Geophysical Research: Solid Earth, 119 (12): 9156-9170 [10.1002/2014jb011552] [Journal Article/Letter]

2014. "Quantifying the Correlation Between the MEI and LOD Variations by Decomposing LOD with Singular Spectrum Analysis.", International Association of Geodesy Symposia, "Earth on the Edge: Science for a Sustainable Planet", Melbourne, Australia, June 28 - July 2, 2011, 139 473-477 [10.1007/978-3-642-37222-3_63] [Article in Book]

2013. "Effects of ICRF2 on the TRF, CRF, and EOP.", International Association of Geodesy Symposia, 138 175-179 [10.1007/978-3-642-32998-2_26] [Article in Book]

2013. "The Construction of ICRF2 and Its Impact on the Terrestrial Reference Frame.", Earth on the Edge: Science for a Sustainable Planet, 185-188 [10.1007/978-3-642-37222-3_23] [Article in Book]

2012. "Comparison of Realizations of the Terrestrial Reference Frame.", International Association of Geodesy Symposia, 138 51-56 [10.1007/978-3-642-32998-2_9] [Article in Book]

2012. "Effects of ICRF2 on the TRF, CRF, and EOP.", REFERENCE FRAMES FOR APPLICATIONS IN GEOSCIENCES, International Association of Geodesy Symposia, "IAG Symposium on Reference Frames for Applications in Geosciences (REFAG)", Marne-la-Vallée, France, Oct: 4-8, 2010, 138 175-179 [10.1007/978-3-642-32998-2_26] [Article in Book]

2010. "Coordinating, Scheduling, Processing and Analyzing IYA09.", International VLBI Service for Geodesy and Astrometry, 2010 General Meeting Proceedings NASA CP/2010-215864: Greenbelt, Maryland, U.S.A.:, NASA CP/2010-215864 90-94 [Full Text] [Proceedings]

2009. "Precise geodesy with the Very Long Baseline Array.", Journal of Geodesy, 83 (9): 859-876 [10.1007/s00190-009-0304-7] [Journal Article/Letter]

1998. "Site displacement due to variation in Earth rotation.", J. Geophysical Research - Solid Earth, 103 (B4): 7337-7350 [10.1029/98JB00149] [Journal Article/Letter]

1998. "VLBI applied to reference frames.", IAG/IGGOS, Munich [Journal Article/Letter]

1998. "Earth rotation yields valuable information about the dynamics of the Earth system.", EOS Trans Am Geophys Union, 79 205-206 [10.1029/98EO00149] [Journal Article/Letter]

1997. "Tidal station displacements.", Journal of Geophysical Research: Solid Earth, 102 (B9): 20469-20477 [10.1029/97jb01515] [Journal Article/Letter]

1996. "Very long baseline interferometry determination of neglected tidal terms in high-frequency Earth orientation variation.", Journal of Geophysical Research: Solid Earth, 101 (B12): 28051-28064 [10.1029/96jb02292] [Journal Article/Letter]

1996. "A bound on the rheology of continental lithosphere using very long baseline interferometry: The velocity of south China with respect to Eurasia.", Journal of Geophysical Research: Solid Earth, 101 (B1): 545-553 [10.1029/95jb02503] [Journal Article/Letter]

1996. "Diurnal/semidiurnal polar motion excited by oceanic tidal angular momentum.", Journal of Geophysical Research, 101 (B9): 20,151-20,163 [10.1029/96JB01649] [Journal Article/Letter]

1994. "Very long baseline interferometry and active rotations of crustal blocks in the Western Transverse Ranges, California.", Geological Society of America Bulletin, 106 (5): 594 [10.1130/0016-7606(1994)106<0594:vlbiaa>2.3.co;2] [Journal Article/Letter]

Non-Refereed

2023. "International VLBI Service for Geodesy and Astrometry (IVS).", Travaux, 43 859-869 [Full Text] [Report]

2019. "5 Year Technology Roadmap for VLBI Global Observing System (VGOS).", Proceedings of the IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium, Yokohama, Japan, 28 July-2 Aug. 2019 , [10.1109/IGARSS.2019.8897849] [Proceedings]

2019. "UT1 Formal Errors from the BA 50 Balanced Scheduling Strategy INT01 R&Ds .", Proceedings of the International VLBI Service for Geodesy and Astrometry 2018 General Meeting: “Global Geodesy and the Role of VGOS – Fundamental to Sustainable Development”, Longyearbyen, Svalbard, June 3-8, 2018, NASA/CP–2019-219039 209-213 [Full Text] [Proceedings]

2019. "Galactic Aberration in VLBI Analysis.", Proceedings of the International VLBI Service for Geodesy and Astrometry 2018 General Meeting: “Global Geodesy and the Role of VGOS–Fundamental to Sustainable Development”, Longyearbyen, Svalbard, June 3-8, 2018, NASA/CP–2019-219039 163-168 [Full Text] [Proceedings]

2019. "Organizing the Continuous VLBI Campaign 2017 (CONT17).", Proceedings of the International VLBI Service for Geodesy and Astrometry 2018 General Meeting: “Global Geodesy and the Role of VGOS–Fundamental to Sustainable Development”, Longyearbyen, Svalbard, June 3-8, 2018, NASA/CP–2019-219039 95-101 [Full Text] [Proceedings]

2017. "Implementation of the vgosDb format at the GSFC VLBI Analysis Center.", Proceedings of the 23rd European VLBI Group for Geodesy and Astrometry Working Meeting, 14-19 May, 2017, Gothenburg, Sweden, 235-237 [Full Text] [Proceedings]

2017. "Reduction of the IVS-INT01 UT1 Formal Error through New Sked Algorithms.", Proceedings of the 23rd European VLBI Group for Geodesy and Astrometry Working Meeting, 14-19 May, 2017, Gothenburg, Sweden, 127-131 [Full Text] [Proceedings]

2017. "Simulation Results for KOKEE12M-WETTZ13S ’Intensives’.", Proceedings of the 23rd European VLBI Group for Geodesy and Astrometry Working Meeting, 14-19 May, 2017, Gothenburg, Sweden, 108-112 [Full Text] [Proceedings]

2017. "Planning of the Continuous VLBI Campaign 2017 (CONT17).", Proceedings of the 23rd European VLBI Group for Geodesy and Astrometry Working Meeting, 14-19 May, 2017, Gothenburg, Sweden, 132-135 [Full Text] [Proceedings]

2017. "Investigating the noise floor of VLBI source positions.", Proceedings of the 23rd European VLBI Group for Geodesy and Astrometry Working Meeting, 14-19 May, 2017, Gothenburg, Sweden, 186-189 [Full Text] [Proceedings]

2016. "Strategic Plan of the IVS for the Period 2016-2025.", International VLBI Service for Geodesy and Astrometry, 2016 General Meeting Proceedings, "New Horizons with VGOS", NASA/CP-2016-219016 3-12 [Full Text] [Proceedings]

2016. "Transition to vgosDb Format.", International VLBI Service for Geodesy and Astrometry, 2016 General Meeting Proceedings, "New Horizons with VGOS", NASA/CP-2016-219016 222-224 [Full Text] [Proceedings]

2016. "Improvement of the IVS-INT01 Sessions through Baynesian Estimation.", International VLBI Service for Geodesy and Astrometry, 2016 General Meeting Proceedings, "New Horizons with VGOS", NASA/CP-2016-219016 229-233 [Full Text] [Proceedings]

2016. "El Nino and VLBI Measured Length of Day.", International VLBI Service for Geodesy and Astrometry, 2016 General Meeting Proceedings, "New Horizons with VGOS", NASA/CP-2016-219016 336-340 [Full Text] [Proceedings]

2015. "Observing Gaia transfer sources in R&D and RDV sessions.", Proceedings of the 22nd Meeting of the European VLBI Group for Geodesy and Astronomy, Sao Miguel, Azores, May 17-21. 2015, 277-280 [Full Text] [Proceedings]

2014. "The NASA Goddard Group's Source Monitoring Database and Program.", Proceedings of the 8th IVS General Meeting: "VGOS: The New VLBI Network", Shanghai, China, March 2-7, 2014, 390-394 [Full Text] [Proceedings]

2014. "Evaluation of the stability of ICRF2 in the past five years using the Allan variance.", Proceedings of the 8th IVS General Meeting: VGOS: The New VLBI Network, Shanghai, China, March 2-7, 2014, [Full Text] [Proceedings]

2013. "Optimal time lags to use in modeling the thermal deformation of VLBI Antennas.", 21st Meeting of the European VLBI Group for Geodesy and Astronomy, held in Espoo, Finland, March 5-8, 2013, Eds: N. Zubko and M. Poutanen, Reports of the Finnish Geodetic Institute, p. 165-168., 165-168 [Proceedings]

2012. "Network Determination and Timeliness of the Rapid Sessions.", International VLBI Service for Geodesy and Astrometry, 2012 General Meeting Proceedings, NASA CP/2012-217504 166-170 [Full Text] [Proceedings]

2012. "The First Release of νSolve.", International VLBI Service for Geodesy and Astrometry, 2012 General Meeting Proceedings, , NASA CP/2012-217504 222-226 [Full Text] [Proceedings]

2012. "Improving VLBI Processing by using Homogeneous Data for Pressure and Temperature.", International VLBI Service for Geodesy and Astrometry, 2012 General Meeting Proceedings, NASA CP/2012-217504 241-245 [Full Text] [Proceedings]

2012. "Regularization of Nutation Time Series at GSFC.", International VLBI Service for Geodesy and Astrometry, 2012 General Meeting Proceedings, , NASA CP/2012-217504 380-384 [Full Text] [Proceedings]

2011. "Strategy to Improve the Homogeneity of Meteorological Data in Mark3 Databases.", 20th Meeting of the European VLBI Group for Geodesy and Astronomy, Bonn, Germany, March 29-30, 2011, 138-141 [Full Text] [Proceedings]

2010. "Proof-of-Concept Studies for a Local Tie Monitoring System.", International VLBI Service for Geodesy and Astrometry, 2010 General Meeting Proceedings NASA CP/2010-215864: Greenbelt, Maryland, U.S.A.:, NASA CP/2010-215864 138-142 [Full Text] [Proceedings]

2010. "IVS Working Group 4: VLBI Data Structures.", International VLBI Service for Geodesy and Astrometry, 2010 General Meeting Proceedings .:, NASA CP/2010-215864 [Full Text] [Proceedings]

2010. "GSFC VLBI analysis center.", 2010 International VLBI Service for Geodesy and Astrometry Annual Report 2009, 231-234 [Full Text] [Report]

2010. "Development of a new VLBI data analysis software.", International VLBI Service for Geodesy and Astrometry, 2010 General Meeting Proceedings, "VLBI2010: From Vision to Reality", NASA CP/2010-215864 197-201 [Full Text] [Proceedings]

Contact Us

For general inquiries about the Sciences and Exploration Directorate.

Jocelyn Lynch

Project Support Specialist

301-286-6066 jocelyn.m.lynch@nasa.gov
Ellie Jeffries

Project Support Specialist

301-286-6066 ellie.jeffries@nasa.gov
Technical issues with this website may be reported to ben.pelletier@nasa.gov.
General inquiries about the scientific programs at NASA's Goddard Space Flight Center may be directed to the Center Office of Communications at 1.301.286.8955.