4. Current research

Solar transition region
Click on image for more information
Fig.28 Time series spectra of the solar atmosphere's transition region (Gerry Doyle).

The Sun is a very dynamic cool star. The solar physics group is studying the outer layers of the Sun and the transport of energy from the Sun's interior through the surface layers to the components of its atmosphere, the chromosphere and the corona.

The solar system group principally researches the main belt asteroids lying between the orbits of Mars and Jupiter; the Edgeworth-Kuiper belt of large comets orbiting the Sun mainly beyond Neptune (the Edgeworth refers to the independent Irish astronomer, Kenneth Essex Edgeworth, who predicted the belt in a 1943 publication - he was a distant cousin of the nineteenth-century novelist Maria Edgeworth); the Öpik-Oort cloud of comets surrounding the solar system in a roughly spherical configuration which stretches about half-way to the nearest stars, some 15 to 25 million million kilometres; the asteroid impact hazard; and meteor streams.

Comet Arend-Roland Fig.29 Comet Arend-Roland photographed with the Armagh Schmidt telescope on 25 April 1957 (E.M. Lindsay/H.H.R. Grossie).
Supersonic Turbulence Fig.30 Supersonic turbulence: turbulent motions in interstellar gas clouds create strong shock waves during star formation (Michael Smith).

A third research group focuses on stellar astrophysics where various branches of the physics of stars are studied, such as: star formation; the life cycles of hot and cool stars; and astrophysical jets and how they interact with the interstellar medium. A variety of space and Earth-based telescopes are used to probe into the interstellar clouds of dust and gas which give birth to the stars. Supercomputer simulations are then executed to provide insight into how these clouds developed over time.

Sunspot cycle and climate
Click on image for more information
Fig.31 The small squares represent the mean temperature at Armagh and the solid histogram represents the length of the sunspot cycle (John Butler).

Finally, staff at Armagh Observatory study solar-system - terrestrial relationships, in particular how the Sun and comet dust affects the Earth's climate. As mentioned earlier, some of this work utilizes our long meteorological series that commenced in December 1794.

These exploratory sojourns into various astronomical phenomena have already given us a deeper appreciation of our physical world and its place in the cosmos. Further researches will undoubtedly take us on pathways leading to a closer understanding of our origins: the ultimate route to our roots.

John McFarland
Armagh Observatory
August 2004

Last Revised: 2009 November 25th