Armenian scientists measure Earth's tidal perturbationsFebruary 21, 2018 - 14:39 AMT PanARMENIAN.Net - Tides on Earth have a far-reaching influence, including disturbing satellites' measurements by affecting their motion. This disturbance can be studied using a model for the gravitational potential of the Earth, taking into account the fact that Earth's shape is not spherical. The LAser RElativity Satellite (LARES), is the best ever relevant test particle to move in the Earth's gravitational field. In a new study published in EPJ Plus, LARES proves its efficiency for high-precision probing of General Relativity and fundamental physics. By studying the Earth's tidal perturbations acting on the LARES, Vahe Gurzadyan from the Center for Cosmology and Astrophysics at Yerevan State University, Armenia, and colleagues demonstrate the value of laser-range satellites for high-precision measurements, Phys.org reports. Specifically, laser-ranged satellites bring increased accuracy in the study and testing of what is referred to in physics as frame dragging. In this study, the authors collect the observations of Earth's tidal perturbations acting on LARES and compare them with two similar laser-ranged satellites: LAGEOS and LAGEOS 2. The team analysed 3.5 years of LARES laser-ranging data, together with that of the two LAGEOS satellites. To extract frame-dragging from the laser-ranging data for high accuracy, the authors model the main gravitational and non-gravitational orbital perturbations. To do so, the team documented 110 significant Earth tide modes for the LARES satellite using the perturbative methods of celestial mechanics and recent data on the satellite's orbit. Frame-dragging is one of the intriguing phenomena of Einstein's theory of General Relativity. It is an effect on space, and is elastic—in other words, it will revert back to its original shape and energy state after force is exerted on it-whereby particles exchange energy with it. This has implications for astrophysics. Read more at: https://phys.org/news/2018-02-laser-ranged-satellite-accurately-earth-tidal.html#jCp Top stories Six total incidents have burned 19 old-growth trees. Friday night 8 trees were torched along the beautiful main entrance. The EU does not intend to conduct military exercises with Armenia, Lead Spokesperson for EU Foreign Affairs and Security Policy Peter Stano says. Hikmet Hajiyev has said that there is no place for USAID operation in Azerbaijan any longer. A telephone conversation between Putin and Pashinyan before the CSTO summit is not planned, Peskov says. Partner news | Czech-Armenian military cooperation discussed in Yerevan A delegation led by the Director General for the Industrial Cooperation Division of the Ministry of Defence of the Czech Republic visited Armenia. Ex-Karabakh leader moved to solitary confinement cell in Baku, his son says David Vardanyan is the son of former Karabakh leader Ruben Vardanyan who who is currently imprisoned in Azerbaijan. Freedom House concerned by mounting reports of police violence in Armenia Freedom House urged Armenian authorities to investigate this pattern of excessive force and inhumane treatment. CSTO recognizes Armenia’s sovereign right to withdraw Tasmagambetov has said that if Armenia decides to leave the organization, “it will be the sovereign right of Armenia.” |