Planck observatory prepares for final shutdown

BBC : The orbiting Planck observatory has provided the clearest picture to date of the cosmic microwave background (CMB)—the still-present radiation released by the initial formation of hydrogen atoms after the Big Bang. In January 2012, Planck ran out of coolant for one of its two primary cameras—the High Frequency Instrument. Since then it has used the Low Frequency Instrument to complete three further full-sky captures that will be used to continue to refine the map of the CMB. Now the European Space Agency is officially shutting down the €600 million ($811 million) telescope. On Wednesday, the agency instructed Planck, which is currently 1.6 million km from Earth, to burn its thrusters to move into an orbit even farther away. A later burn will completely empty the fuel tank to avoid the risk of a future explosion and the resulting debris. On 23 October, scientists will disconnect the batteries and turn off the observatory’s transmitters, leaving it to drift, unpowered, in a slow orbit around the Sun.