Determining the fundamental nature of the solar atmosphere: applying Bayesian analysis methods to Hinode observations

Lead Research Organisation: University of Central Lancashire
Department Name: Sch of Comput Engin and Physical Sci


To say the Sun is important really is an understatement- we are here because our closest star provides the necessary light and heat required for life on Earth. We are in a golden era of solar-terrestrial research at this time with several major satellite missions revolutionising our understanding of the flow of energy from the Sun to the Earth. In particular, a joint Japanese, British and American satellite called Hinode (meaning 'sunrise' in Japanese) was launched in late 2006. Using a combination of instruments that observe the light from the Sun in optical, Extreme Ultraviolet and X-ray wavelengths, Hinode will study the intimate relationship between the Sun's magnetic field and its outer atmospheric layers. One of the remaining unresolved questions in solar physics is why the temperature of this outer atmosphere rises from 5780 K at the photosphere (where the visible light originates) to millions degrees in the outermost parts- the corona. Clearly as you move away from a heat source (in this case the energy generated by nuclear reactions at the core of the Sun), the temperature should fall away. Some additional heating must be dumping extra energy directly into the corona to create this counter-intuitive temperature rise. Several mechanisms have been suggested which are all centred around the Sun's magnetic field. However, there is as yet no scientific consensus on the specific details on how this 'coronal heating problem' can be solved. In particular, a significant proportion of the radiation emitted from the solar corona is concentrated along well-defined loop-like arches. These loops are the basic structural elements of the atmosphere and coincide with the magnetic field as it rises out though the surface of the star, 'trapping' the electrified gases (the plasma) along its length. The research proposed in this application seeks to use Hinode to probe the corona like never before. Part of the work will deal with detecting and measuring 'magnetic sound waves' (termed magnetoacoustic oscillations) as they travel along loops, carrying energy through the solar atmosphere. Also, by using techniques in solar spectroscopy, we will measure remotely the temperature and density along loops to help us further understand the nature of the corona and where this extra energy could be being deposited. To fully examine our observations, we will use a set of statistical tools called Bayesian analysis methods- these techniques allow us to add into our investigations as much prior information or knowledge of the loops as possible. This will be a new way in Solar Physics to help us compare our theoretical models with these latest satellite observations.
Description The nature of coronal loops and the possible heating mechanisms
Exploitation Route Employed by coronal loop community
Sectors Education,Other

Description As part of public engagement and outreach events.
First Year Of Impact 2005
Sector Other
Impact Types Cultural

Description NASA Marshall SFC 
Organisation National Aeronautics and Space Administration (NASA)
Department Marshall Space Flight Center
Country United States 
Sector Public 
PI Contribution laid groundwork for science collaboration on Hi-C sounding rocket programme.
Collaborator Contribution UCLan provided camera electronic box, software support plus scientific exploitation of the dat related to coronal dynamics.
Impact Multiple journal papers (including a paper in Nature) and numerous presentations etc.
Start Year 2011
Description IOP IRELAND 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? Yes
Type Of Presentation Keynote/Invited Speaker
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Lectures at multiple locations around Ireland
Year(s) Of Engagement Activity 2008
Description SunBeam 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Type Of Presentation Keynote/Invited Speaker
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact A night-time art installation with Prof. Chris Meigh-Andrews where solar
observations are projected onto large solar cell trackers. The concept was to create an artwork
where the energy harvested during the day can then be used to undertake the artwork
projection that evening. Media coverage included BBC website (
lancashire-13332642) and BBC North West TV news as well as local radio/press.

Invitation to speak at other outreach events
Year(s) Of Engagement Activity 2011