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  • The Sun's gravitational field deflects the apparent positions of close objects in accordance with the formulae of general relativity. Optical astrometry is used to test the prediction, but only with the stars close to the Sun and only during total Solar eclipses. Nowadays, more advanced technique, geodetic Very Long Baseline Interferometry (VLBI) is applied for testing of general relativity with precision about 0.01 percent. The geodetic VLBI is capable of measuring the gravitational delay based on the differential Shapiro's delay. By reason, the gravitational delay is equivalent to the deflection of the light from distant radio sources and could be measured at any time and across the whole sky. In accordance with the theory, all celestial objects display annual circular motion with the magnitude proportional to their ecliptic latitude due to the Earth orbital motion. In particular, the objects near the ecliptic pole draw an annual circle with magnitude of 4 millisecond of arc. In contrast to a single optical telescope, a single ground-based VLBI interferometer is made of two radio telescopes separated by several thousand kilometers. This provides an additional advantage to detect a secondary light deflection angle caused by the parallactic shift of the Sun as observed from both ends of the interferometer. This effect is proportional to the baseline length and is about 0".01 for grazing light at baseline of 8000 km. It could be used in future space interplanetary VLBI missions with baseline length of one billion kilometers (comparable to the Jupiter orbit size) for direct detection of invisible mass from extragalactic objects.

  • Interpretative report from the GA0340/SOL5754 marine survey of the Leveque Shelf

  • This dataset reflects the boundaries of those Indigenous Land Use Agreements (ILUA's) that have entered the notification process or have been registered and placed on the Register of Indigenous Land Use Agreements (s199A, Native Title Act; Commonwealth). This is a national dataset. Aspatial attribution includes National Native Title Tribunal number, Name, Agreement Type, Proponent, Area and Registration Date. Citation: ANZLIC unique identifier: ANZCW1101000005 Title: Registered and Notified Indigenous Land Use Agreements (ILUA) - agreement boundaries and core attributes about agreement Custodian: National Native Title Tribunal Jurisdiction: Australia

  • the broad geological blocks from Archaean in the west, through Proterozoic in the centre, to Palaeozoic-Cainozoic in the east, are well presented in the 3-D electrical conductivity model as simple lower conductivity structures. In addition, the model shows conductivity contrast in the western craton, characteristic of enhanced conductivity structures which separate the cratonic blocks, and enhanced conductivity anomalies presented in eastern Australia.

  • Groundwater Branch flyer - 2 page glossy handout

  • Digital elevation models (DEMs) provide basic information about the shape of the earth. This information is fundamental for understanding and modelling natural hazards and their consequences. The low resolution and accuracy of the current generation of freely available global DEMs means inappropriate use can lead to dangerously misinformed disaster management decisions being made, particularly at the local level. Investing in high resolution, high accuracy global DEMs and making them freely available to the global community would have many benefits to society, one of which would be better informed disaster management decision making.

  • These datasets cover approximately 3360 sq km of coastal areas of Northern and South-eastern Tasmania. The project covered three areas: - Greater Hobart 1283 square km - Huon Valley 460 square km - Launceston, Burnie, Devonport 1612 square km This project, undertaken by RPS Mapping on behalf of Geoscience Australia produced accurate LiDAR and derived products to ICSM specifications and medium format digital ortho-photo mosaics.

  • This project consists of data that has been reprocessed by RPS and AAM for the purpose of creating an improved Victorian coastal DEM including contours based on the original data acquired in 2007. The purpose of this project is to reclassify the original level 2 classification LiDAR data into level 3 for input to a higher accuracy ICSM Level 3 classification (Level 3 DEM). LiDAR (Light Detection and Ranging) is an airborne remote sensing technique for rapid collection of terrain data. The sensor used for this LiDAR project collected XYZ and Intensity data for first and last return by bouncing a pulse from the aircraft to the surface that enables the height and intensity values to be calculated. From the raw LiDAR data, a suite of elevation products was generated including DEM and Contours. Project Products: DEM, Contours, raw LiDAR.

  • This dataset is the most current national compilation of catchment scale land use data for Australia (CLUM), as at March 2015. It is a seamless raster dataset that combines land use data for all state and territory jurisdictions, compiled at a resolution of 50 metres by 50 metres. It has been compiled from vector land use datasets collected as part of state and territory mapping programs through the Australian Collaborative Land Use and Management Program (ACLUMP). Catchment scale land use data was produced by combining land tenure and other types of land use information, fine-scale satellite data and information collected in the field. The date of mapping (1997 to 2014) and scale of mapping (1:20 000 to 1:250 000) vary, reflecting the source data capture date and scale. This information is provided in a supporting polygon dataset.