ASKAP's wide field-of-view, large spectral bandwidth, fast survey speed, excellent u-v coverage, southern hemisphere location and radio quiet site will make it an unprecedented synoptic telescope. These unique features will allow ASKAP to make substantial advances in key areas of SKA science, including:
- Galaxy formation and gas evolution in the nearby Universe through extragalactic HI surveys
- Evolution, formation and population of galaxies across cosmic time via high resolution, confusion limited, continuum surveys
- Characterisation of the radio transient sky through detection and monitoring (including VLBI) of transient and variable sources, and
- Evolution of magnetic fields in galaxies over cosmic time through polarization surveys.
ASKAP Early Science Program
In May 2013, CSIRO Astronomy and Space Science announced its intention to develop an early science program for ASKAP. The ASKAP Early Science is a program of observations designed to explore new scientific parameters with ASKAP before the construction of the array is complete, and also to produce scientifically useful data.
It will commence when an array of twelve ASKAP antennas fitted with CSIRO's Mk II phased array feeds (the instrument known as ASKAP-12) has been commissioned and scientifically verified. Early science observations will be carried out in parallel with the deployment of the Mk II phased array feeds on further ASKAP antennas.
The latest version of the ASKAP Early Science Program (September 2015) incorporates the early science software pipeline, a new baseline description of the program, FAQs and an estimate of likely observing time available for early science observations.
ASKAP Early Science Community Workshops
The first ASKAP Early Science Workshop [announcement, PDF file] was held in 2013. Presentations covering a broad range of scientific interests described some of the ground-breaking scientific questions that could be addressed using ASKAP’s 12-antenna array. Workshops have been held on a regular basis (see 2014 recap and 2015 outcomes) and the ASKAP Early Science Forum is held monthly. To get involved in ASKAP Early Science, please contact the ASKAP Project Scientist.
Survey Science Projects
During ASKAP’s first five years of operation at least 75% of its time will be used for large Survey Science Projects, each needing more than 1,500 hours to complete and all designed to make use of the telescope’s unique capabilities. Ten major Survey Science Projects, representing 363 investigators from 131 institutions were selected in 2009 by an international panel, with the decision based on scientific merit and operational feasibility. Read more on the ASKAP Survey Science Projects.
The Boolardy Engineering Test Array (BETA), an array of six ASKAP antennas installed with Mk I phased array feed receivers, is already producing some interesting initial science results.
There are a number of ways to discover ASKAP science papers:
- An automatically generated list of science papers that include reference to ASKAP and its science.
- A list of CSIRO publications collated based on reference to data taken with ATNF facilities (including ASKAP) or by CASS staff members.
RFI analysis plots
The following RFI analysis plots comprise several month's worth of observing time with the Boolardy Engineering Test Array (BETA), capturing permanent as well as intermittent RFI sources as they were affecting the bands. The data were binned to 1 MHz width for the summary plots. The frequencies where the main interferers start or stop causing astronomical signal degradation have been annotated on the plots.
Click on the thumbnails for charts and waterfall plots.
Band 1: 712-1012 MHz.
Band 1: 712-1012 MHz with ducting.
Band 2: 968-1272 MHz.
Band 3: 1224-1528 MHz.
Band 4: 1480-1784 MHz.
- The yellow bands at the bottom of the summary plots show the spectrum allocation of the given frequencies, whereas blue (satellite), brown (terrestrial) or cyan (aviation) lines show actual known emitters from mobile communication, fixed communication links, aviation sources as well as satellite sources.
- The waterfall plots are shorter excerpts usually a few hours long (time is in the Y axis) highlighting the temporal function of some of the RFI. It is interesting to see that e.g. satellites may be absent for some period and then suddenly dominate the signal very strongly.
- They are moving targets that are at some point moving through the beam of the telescope. When that happens, they are completely wiping out any astronomical signal. The waterfall plots show the correlated signal between antennas ak01 and ak03, a rather short baseline of 37m length.
Contact the ASKAP Project Scientist for further information.
- ASKAP Update: A newsletter for anyone interested in ASKAP progress
- ASKAP Commissioning Update: A newsletter for the astronomy community.
- Information for users of ASKAP
- Journal paper 'Science with the Australian Square Kilometre Array Pathfinder', Johnston et al. (2007) Publications of the Astronomical Society of Australia 24(4) 174–188
- Journal paper 'Science with ASKAP', Johnston et al. (2008) Experimental Astronomy 22(3) 151–27