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Beidou II (COMPASS-G2), China’s second geostationary navigation satellite, was launched on April 15th from the Xichang satellite Launch Center, in Sichuan Province, via a CZ-3C Chang Zheng-3C (CZ3C-2) launch vehicle. The launch is the first in a series of launches announced by China to form the complete Compass constellation. This constellation of satellites will consist of approximately 30 vehicles, including 27 MEO satellites, with nine satellites for each orbit plane – and four GSO satellites (58.75 degrees E, 80 degrees E, 110.5 degrees E, and 140 degrees E). The BeiDou-2 was developed from the DFH-3 satellite platform and has a lifespan of 8 years.

The Compass Navigation Satellite System (CNSS) is China’s second-generation satellite navigation system capable of providing continuous, real-time passive 3D geo-spatial positioning and speed measurement.

The first phase of the project will deal with coverage for the Chinese territory. However, a future Compass constellation will cover the entire globe.

Source : http://www.nasaspaceflight.com

Aiming to bolster India’s defence surveillance capabilities, ISRO today successfully launched its first all-weather radar imaging satellite, RISAT -2. The PSLV-C12 (Polar Satellite Launch Vehicle), carrying 300-kg RISAT and 40-kg micro educational satellite ANUSAT (developed by Anna University) lifted off from ISRO’s Satish Dhawan space Centre here at 6:45 am and placed into 550 km orbit around earth.The PSLV, weighing 230 tonnes at the time of launch, soared into a clear sky from the spaceport in Sriharikota, about 90 km north of Chennai. At the end of the 48-hour countdown, the 44-metre tall four-stage PSLV-C12 blasted off from the second launch pad with the ignition of the core first stage.RISAT has all-weather capability to take images of the Earth and would also be beneficial in mapping and managing natural disasters, such as floods and landslides, besides amplifying defence surveillance capabilities of the nation. It would also help keep track of ships at seat that could pose a threat.A jubilant ISRO Chairman G Madhavan Nair said “the year 2009 has started off well. The final moments of the launch were more thrilling than a cricket match as we hit a few boundaries and bowled some googlies.” Nair said the performance of the PSLV-C12 launch vehicle was “precise and on the dot”. As per specifications, RISAT is different from previous remote sensing satellites as it uses Synthetic Aperture Radar (SAR), equipped with many antennas to receive signals that are processed into high-resolution pictures.

Source : http://www.samaylive.com

The Earth's "plasma fountain", showing oxygen, helium, and hydrogen ions which gush into space from regions near the Earth's poles. The faint yellow area shown above the north pole represents gas lost from Earth into space; the green area is the aurora borealis-or plasma energy pouring back into the atmosphere.

Plasma Fountain is in the North Pole of the Earth. The figure depicts the oxygen, helium, and hydrogen ions that gush into space from regions near the Earth’s poles. The faint yellow gas shown above the north pole represents gas lost from Earth into space; the green gas is the aurora borealis-or plasma energy pouring back into the atmosphere.Plasma is a partially ionized gas, in which a certain proportion of electrons are free rather than being bound to an atom or molecule. The ability of the positive and negative charges to move somewhat independently makes the plasma electrically conductive so that it responds strongly to electromagnetic fields. Plasma therefore has properties quite unlike those of solids, liquids or gases and is considered to be a distinct state of matter. Plasma typically takes the form of neutral gas-like clouds, as seen, for example, in the case of stars. Like gas, plasma does not have a definite shape or a definite volume unless enclosed in a container, but unlike gas, in the influence of a magnetic field, it may form structures such as filaments, beams and double layers .Plasma was first identified in a Crookes tube, and so described by Sir William Crookes in 1879 (he called it “radiant matter”).The nature of the Crookes tube “cathode ray” matter was subsequently identified by British physicist Sir J.J. Thomson in 1897,and dubbed “plasma” by Irving Langmuir in 1928,perhaps because it reminded him of a blood plasma.

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