In the show this time, Dr Rob Crittenden tells us about the Microwave Background, Dr Bryan Rees talks about Planetary Nebulae in this month's JodBite, and your astronomical questions are answered by Dr Iain McDonald in Ask an Astronomer.
JodBite with Dr Bryan Rees
Dr Bryan Rees talks to us about Planetary Nebulae - the remnants of stars such as our Sun at the end of their lives. When they reach the final stages of their evolution, red giant stars eject their outer layers into space, creating these beautiful objects. A recent paper, published as part of Bryan's thesis, shows that certain kinds of planetary nebulae known as Bipolar nebulae (featured in the cover pic!) seem to align themselves along a certain direction in the sky .
Interview with Dr Rob Crittenden
We talk to Dr Robert Crittenden of the University of Portsmouth's Institute of Cosmology and Gravitation about non-Gaussianity in the cosmic microwave background (CMB). He tells us how the CMB can tell us about the very early universe, one method we use to examine the non-Gaussianty of the temperature fluctuations. He gives us a description of inflation theory and how it can explain how the universe is the way it is today. He goes on to explain how his research has a key role in understanding the non-Gaussianity we measure in the CMB. We briefly discuss how research into the early universe can tell us about particle physics beyond the standard model.
Ask an Astronomer
Dr Iain McDonald answers your astronomical questions:
- Mark asks: "What is the mass distribution of stars in our galaxy and universe?"
- Pete Ellinger says: "What provides the impedance to the progression of light through a vacuum that reduces the velocity to 299,792,458 m/s?"
- Jerome Tremblay says: "Is the universe flat or curved?"
Odds and Ends
Scientists in the USA have reported at a conference that 'diamond rain' could be falling on Jupiter and Saturn. It was thought previously that Uranus and Neptune can harbour gemstones but that the atmospheres of Saturn and Jupiter would be unsuitable. However, new atmospheric data suggests that Saturn and Jupiter could have diamonds forming in their atmospheres.
An international team of scientists have discovered an object, named PSO J318.5-22 floating freely through space. They were using the PS1 wide-field telescope in Maui to find brown dwarfs - stars whose mass is below the minimum requirement for fusion of hydrogen to take place. However, PSO J318.5-22 is not a brown dwarf. Intriguingly, it shares many characteristics with extra-solar planets, making it possibly the first planet to be discovered without any host star. An article was published in Science Daily, and the paper which is due to be published by the Astrophysical Journal Letters can be found on ArXiv.
The prediction and recent discovery of the Higgs boson - honoured by the 2013 Nobel prize in Physics - may have an impact on cosmology, according to a recent paper in Physical Review Letters. Interactions between the Higgs and its theorized anti-particle in the very early universe could be responsible for the conundrum known as matter-antimatter asymmetry . Furthermore, interactions between the Higgs and dark matter could be connected to the ratios between visible matter and dark matter that we see today - and Higgs experiments could prove to be a testing ground for dark matter. Read more about this paper here .
|JodBite:||Dr Bryan Rees and Indy Leclercq|
|Interview:||Dr Rob Crittenden and Chris Wallis|
|Ask An Astronomer:||Dr Iain McDonald and Christina Smith|
|Presenters:||Christina Smith, Indy Leclercq and Fiona Healy|
|Editors:||Indy Leclercq, Sally Cooper and Christina Smith|
|Segment Voice:||Mike Peel|
|Website:||Sally Cooper and Stuart Lowe|
|Cover art:||This image shows the bipolar planetary nebula PN Hb 12, popularly known as Hubble 12, in the constellation of Cassiopeia. CREDIT: NASA / ESA. Acknowledgement: Josh Barrington.|