Interferogram images derived from repeat-pass paceborne synthetic aperture radar systems exhibit artifacts due to the time and space variations of atmospheric water vapor. Other tropospheric variations, such as pressure and temperature, also induce distortions, but the effects are smaller in magnitude and more evenly distributed throughout the interferogram than the wet troposphere term. Spatia...

Interferogram images derived from repeat-pass spaceborne synthetic aperture radar systems exhibit artifacts due to the time and space variations of atmospheric water vapor. Other tropospheric variations, such as pressure and temperature, also induce distortions, but the effects are smaller in magnitude and more evenly distributed throughout the interferogram than the wet troposphere term. Spati...

This article is a sort of sequel of the earlier extensive review by Saha (1999a) where emphasis was laid down on the ground based single aperture, as well as on the working long baseline optical interferometers (LBI) situated at the various observatories across the globe that are producing a large amount of astronomical results. Since the future of high resolution astronomy lies with the new ge...

The 10-meter space radio telescope Spectrum-R was successfully launched on July 18, 2011, and unfurled several days later. The space element of the ground-space very long baseline interferometer RadioAstron covers four frequency bands from 92 to 1.3 cm and provides baselines up to 350,000 km. This allows to study space objects with a resolution as high as about 10 microarcsecond. The mission de...

We detected phase jumps of the Free Core Nutation (FCN) of the Earth directly from the analysis of the Very Long Baseline Interferometer (VLBI) observation of the Earth rotation for the period 1984-2003 by applying the Weighted Wavelet Z-Transform (WWZ) method and the Short-time Periodogram with the Gabor function (SPG) method. During the period, the FCN had two significant phase jumps in 1992 ...