Reports - 2010

Pictures from the Hubble Site

Astronomy Benalla  General Meeting Presentations - Wednesday 16th June 2010  The Solar Dynamic Observatory. Presented by Astronomy Benalla President Rupe Cheetham. The Solar Dynamic Observatory (SDO) built at the Goddard Space Flight Centre (GSFC) is a NASA mission that will observe the Sun for 5 + years with the aim of developing an understanding of how the Sun-Earth system directly affects human life and society. SDO will record how the Sun’s magnetic field is generated and investigate the mechanisms of the Sun’s interior sources as they relate to the surface magnetic fields. Also studied  will be how these fields are stored and then converted and released into the heliosphere in the form of the solar wind. SDO weighs 290 kg. Together with 1,400 kg of fuel SDO was launched from Cape Canaveral on 11^th February 2010, aboard an Atlas V 401 rocket. SDO was placed in a geosynchronous orbit at an altitude of 36,000 km. This observatory is considered a follow-on from the Solar and Heliospheric Observatory (SOHO), launched in December 1995. Data recorded by SDO will be at a far higher resolution than that captured by SOHO. SDO is a three-axis-stabilised craft with two solar arrays and two high gain antennas.  There are four cameras and three main instruments: Extreme Variability Experiment (EVE). EVE will measure the extreme-ultraviolet (EUV) variability irradiance with improved temporal cadence accuracy and precision compared to previous measurements (e.g. SOHO). The Sun’s output of energetic EUV photons is primarily what heats the Earth’s upper atmosphere and creates the ionosphere. Also recorded will be radiation changes, from moment-to-moment; these have an impact on atmospheric heating and satellite drag and can also cause communication system degradation, including disruption of Global Positioning Systems. Measurements are recorded every ten seconds over its duty cycle. Helioseismic and Magnetic Imager (HMI). HMI produces data to determine the interior sources and mechanisms of solar variability and also how the physical processes inside the Sun relate to the magnetic field activity. HMI will take high- resolution measurements of longitudinal and vector magnetic fields over the entire visible disk. Atmospheric Imaging Assembly (AIA). AIA uses the four telescopes to provide individual feeds to the four cameras for imaging the Sun in several UV and EUV pass bands, at high spatial and temporal resolution. Data is captured in wavelengths less than 0.1 nanometres (100,000,000,000^th of a meter) and will generate 1.5 terabytes of data per day, beaming back to laboratories on Earth 150 million bits of data every second (equivalent to 380 full-length movies). Data is made available to researchers as soon as possible after it has been received.               Further Information: http://sdo.gsfc.nasa.gov