Jim Ray

Dr. Jim Ray obtained a degree in space physics and astronomy from Rice University in Houston in 1980. After two post-doctoral fellowships, he worked for more than seven years as a member of the NASA Very Long Baseline Interferometry (VLBI) group at Goddard Space Flight Center, Greenbelt, Maryland. He later moved to the Geosciences Laboratory of the National Oceanographic and Atmospheric Administration (NOAA), where he remained for more than five years, first leading the VLBI analysis effort there, then joining the GPS analysis program. Afterwards, he was head of the Earth Orientation Department at the U.S. Naval Observatory (USNO) for five years. Recently he joined NOAA¿s National Geodetic Survey working on GPS and International GPS Service (IGS) projects. He also serves on the IGS Governing Board and acts as co-chair of the joint IGS/Bureau International des Poids et Mesures Time Transfer Pilot Project.

Blog IGSMAIL-6356 - Upcoming switch to IGS08 reference frame and the consequences to the GPS users (III) March 24, 2011 By: Jim Ray As announced in the previous post, the IGS will switch from the (IGS05 + igs05.atx) framework to (IGS08 + igs08.atx) in the coming weeks. Many users have accumulated results expressed in the old framework, either based on the regular IGS operational products since November 2006, or in concert with...more >>
Blog IGSMAIL-6354 - Upcoming switch to IGS08 reference frame and the consequences to the GPS users (I) March 24, 2011 By: Jim Ray The IGS will soon adopt a new Reference Frame, called IGS08, as the basis of its products. IGS08 is closely related to ITRF2008, released in May 2010. An updated set of satellite and ground antenna calibrations, igs08.atx, will also become effective at the same time and should be used together with...more >>
News Precise GPS Orbital Data from IGS: Current Status January 14, 2010 By: Jake Griffiths,Jim Ray The International GNSS Service (IGS) has further improved the quality of the products made available to the GNSS community. The accuracy of the Final GPS Orbits (available weekly with a delay of about two weeks) from IGS is now about 2 centimeters, based on an analysis of discontinuties between...more >>
	Article New IGS Clock Products: A Global Time Transfer Assessment November 1, 2002 By: Jim Ray,Ken Senior The International GPS Service has a new suite of clock products.