The Universe in 4D

Tuesday 20th March, 2018

We were pleased to welcome Dr Christ Baddiley who came to talk to us about "The Universe in 4D". He is a retired physicist but still remains active in the field by developing mathematical models of skyglow, working on improving astronomical equipment as well as offering talks on subjects ranging from cosmological theories to the history of astronomy.

Dr Baddiley began by saying he had inherited a property from his parents between Hereford and Worcester, which was located in a fairly dark site and where he does most of his observing. His "Mathon Observatory" is a shed with a roof that slides off and it has a control room built on the side that houses other equipment such as computers to drive the telescopes. One of the instruments is an all-sky camera that he uses to measure light pollution. You can even stay at his house and view the observatory by booking accommodation through the Airbnb website.

He then showed us various pictures of sky objects that he had imaged from Mathon Observatory as well as other photographs from his travels abroad. One of the images showed the total solar eclipse that had taken place across the continental USA. He had travelled to Wyoming to capture the event that had taken place in the morning of August 21st last year. Further trips had seen him capture another total solar eclipse from Libya as well as aurorae from Iceland.

He continued by saying that he has been modelling the effects of light pollution on the sky for many years and, sadly, the lighting upgrades to the blue-white LED streetlighting had not helped the situation. The darkest nights at Mathon Observatory occur when there is mist or cloud to block the stray light but those conditions are hopeless for astronomical observations. Sometimes he has even noted that low clouds on the horizon block the stray light emanating from the surrounding cities of Hereford and Worcester.

The highlight of the evening was his slide show that needed the use of red and green stereo glasses that were handed out to the audience. He showed us perspective views of the Solar System, stars, the Milky Way and far distant galaxies. Most of the audience said that they could appreciate the 3D effect and that it improved with time spent looking at the pictures. In fact, from the back of the room, some of the stars appeared to be floating in between the heads of those sitting further forward.

Due to the fact that the images were computer generated he could also make the star fields rotate so that you could see all the way around them. He also manipulated the pictures so that the stars moved as time progressed. This made them appear quite different to the patterns of stars that we can only view from the direction of Earth.