Over the past summer I had the opportunity to undertake a summer placement at Cardiff University School of Physics and Astronomy through the Nuffield Science Bursary scheme, under the supervision of Dr Edward Gomez. The main aim of this project was to explore the final evolutionary phases of a star's life. We looked at both large mass and small mass stars and their end stages, comprising of supernovae and planetary nebulae.
During the first part of the project, we investigated the supernova remnant M1 (the Crab Nebula) using data from 2004 to 2011. A selection of images from this period, taken with the Faulkes telescopes, was compiled into a short film clip which was then used to study the progress of the nebula’s expansion over time. Three “Reference Points” were chosen and tracked through the progression of these images. Using this we determined the distance each point was from the central pulsar at a given date, and found a value for the velocity at which the expansion was progressing.
In the second part of the project we studied the final evolutionary stages of low to intermediate mass stars (< 8 Mʘ), and had the opportunity to observe original images using three different telescopes in the Las Cumbres Observatory global telescope network, including FTS (Australia), FTN (Hawaii) and the Byrne Observatory at Sedgwick (California). Using these telescopes, the VAO - Virtual Astronomical Observatory and other resources available to us, including from the LCOGT.Net observation archive, a variety of multi-wavelength data on specifically selected planetary nebulae was gathered. This enabled us to make a catalogue of composite images of these planetary by looking at a series of different filters including visible light. After studying a paper outlining the misclassification of Planetary Nebulae (Frew et al. 2011), and focusing on a single asymmetric planetary nebulae as part of a collaborative project called Space To Grow between Macquarrie University and year 11 high school students in Australia. Our intention was to further analyse these nebulae to determine whether or not they were true planetary nebulae, and not simply objects that resemble one, however due to the limited time we had available for this project we were unable to further analyse our chosen planetary nebulae as we had wanted.
From what we observed of the Crab Nebula data we can conclude there is an overall expansion in the supernovae remnant over time, but it is unclear as to how this expansion is changing with time. By looking at more, higher quality images the accuracy of the current data would be improved and would further the overall research and a better understanding of how this research could be duplicated to find out similar information regarding other comparable nebulae could also be obtained.
Our results also show a consistent diversity in the shape and size of planetary nebulae. By using a different data archive a variety of more useful data sets could be obtained. Given more time and the improved images more observations could be made and the reliability of the gathered information improved. This would potentially allow us to further analyse these objects in the future, in order to continue the research in to these planetary nebulae and to expand on the existing knowledge of the diversities within the categories of planetary nebulae.
This news item was written by our Nuffield summer student, Chantal Warren from St John's College, Cardiff.
