In the show this time, Elaine Sadler talks to us about talks to us about Australian Square Kilometre Array Pathfinder (ASKAP), Dr. Indy Leclercq tells us about his diffuse galactic emission research and your astronomical questions are answered by Fiona, Ben and George in Ask an Astronomer.
Jodbite with Dr. Indy Leclercq
In this month's Jodbite we interview former Jodcast producer Dr. Indy Leclercq about his PhD thesis and recent viva. The title of Indy's thesis was "The Local Radio Sky: High Frequency Resolution Single Dish Studies of Polarized Galactic Synchrotron Emission around 1.4 GHz". Indy tells us all about his viva (which took place the day before recording!), and we discuss his PhD project, for which he used the Arecibo telescope to study the polarization structure of diffuse emission in the galaxy.
Interview with Professor Elaine Sadler
Minnie interviews Dr. Elaine Sadler, director of the Centre of Excellence for All-sky Astrophysics (CAASTRO). In this interview, Dr. Sadler discusses the work that CAASTRO does, and she also discusses her involvement with the Australian Square Kilometer Array Pathfinder (ASKAP) and how that telescope is being used to prepare for the operation of the Square Kilometer Array (SKA) as well as how it is being used to search for hydrogen gas in very distant galaxies seen forming in the early universe.
Ask an Astronomer
Fiona, Ben and George answer your astronomical questions: Galaxy Collisions, telescopes and asteroids
- Alex asks, "What would happen if our galaxy collided with another?"
- Oliver asks us what kind of object are visible with telescopes
- Gillian wants to know about the ever-present dangers from space
Odds and Ends
- Fiona recently tuned in to a live broadcast of the launch of SpaceX's Falcon 9 rocket, which was depositing 10 new Iridium satellites into orbit. You can watch the exciting footage here.
- There is some discussion over the phrase "We are made of Star Dust". Ian prefers Carl Sagan, who's a personal hero, while others opt for Joni Mitchell/Neil Young. Whoever originated it, this is to Ian a magical phrase that makes astronomy relevant to all of us.
The Sloan Digital Sky Survey recently made its Thirteenth Data Release available advertising it with the phrase "We are made of star dust". It contains data from APOGEE (Apache Point Observatory Galactic Evolution Experiment). APOGEE used the spectrograph from the 2.5m near infra-red telescope to measure the spectra of 150,000 stars in the Milky Way.
The data set contains data on the CHNOPS elements (Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus and Sulphur). These elements make up 97% of our bodies while making up less than 1% of the elements in the Universe.
The APOGEE team found that stars closer to the centre of the Milky Way contains a higher proportion of the CHNOPS elements. Not in itself a surprise. The stars near the centre of the Milky Way are likely to be older than those in our locality. The team are making no claims about the likelihood of life in different parts of the galaxy. As a team member John Holtzman points out "we don't know what the minimum amount of CHNOPS would need to be for life to arise, especially since we don't really know how that happens in any detail!"
The team will be using the data to better understand star formation and evolution in the Milky Way.
This leads to the thought as to whether we are being rather “carbon-centric” in our ideas about life, if it exists, elsewhere in the Universe. Granted, Carbon is an exceedingly good element for life. It can make 4 bonds. Those bonds can be single, double or triple. The single bond is stable but can be broken (which is useful for respiration). Other elements like Silicon or Arsenic could form long chains but the chemistry is unlikely to work unless conditions are considerably different to those on Earth. What is more likely is that life could use ssolvents other than liquid water. We know that the surface of Saturn's largest moon, Titan, contains oceans made out of liquid Methane and Ethane. Could life use liquid Methane rather than water? If so, our idea of what constitutes the "Goldilocks zone" - orbits around stars in which planets could support life - may have to change.
So, what are the most outlandish aliens that we have come across in fiction? Iain. M. Banks wrote about clouds of gas that communicated with each other. Douglas Adams talked of "Super intelligent shades of the colour blue". Ian's personal favourites are the Cheela, aliens living on the surface of a neutron star in Robert. L. Forward's novel, Dragons Egg.
Life elsewhere in the Universe is likely to be stranger than we could possibly imagine. The trick will be to recognise it for what it is.
|Interview:||Dr Indy Leclercq with Fiona Healy and Charlie Walker|
|Interview:||Professor Elaine Sadler with Minnie Mao|
|Ask An Astronomer:||George Bendo, Fiona Healy and Benjamin Shaw|
|Presenters:||Monique Henson, Ian Evans and Fiona Healy|
|Editors:||Damien Trinh, George Bendo, Tom Scragg and Charlie Walker|
|Website:||Benjamin Shaw and Stuart Lowe|
|Cover art:||CREDIT: Indy Leclercq|