Highlights in Remote-Sensing Observations of the Inner Heliosphere During 2011 and 2012 Focussing on the EISCAT and LOFAR Radio-Telescope Systems

Significant progress has been made over the last two years on the implementation of, and science resulting from, radio remote-sensing observations of the inner heliosphere using the European Incoherent SCATter (EISCAT) radar and the LOw Frequency ARray (LOFAR) radio-telescope systems. LOFAR is a precursor to the Square Kilometre Array (SKA), the world's largest ever radio telescope system. Here, we highlight some of these advances in radio remote-sensing heliospheric science, and where appropriate, we show examples of comparative and joint studies with data from other remote-sensing observations as well as with modelling of the inner heliosphere. Data from 2011 and 2012 will provide the foci of this work, although historical comparisons may be necessary. EISCAT has been used for relatively-high-frequency observations of IPS since the early 1990s, and LOFAR successfully since 2011. The lower observing frequency of LOFAR allows us to probe further from the Sun in IPS that using EISCAT; however, two of the three mainland EISCAT telescopes are due to undergo a conversion to VHF frequencies (224 MHz) through late summer of 2012. This will result in a direct-observational overlap towards the high-frequency end of the observing capabilities using LOFAR (maximum observing frequency of 250 MHz) for IPS studies. Tests, where possible, will be explored with this new receiver system along with tests of the new EISCAT_3D test-bed, the Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA). This work comes one year following the death of Dr. Andy Breen who was one of the early pioneers of the IPS experiment on the early EISCAT system.