Turn your smartphone into a cosmic ray hunter with the free CREDO app! Currently available on Android (any Apple developers out there get in contact) and already with 2.5 million detections the growing userbase is helping us search for the most extreme events in the Universe. Not that this helped me with Virginia on News Breakfast who asked me some seriously tough (but as usual, brilliant) questions on the health risks of Cosmic Rays.Read More
Filtering by Tag: Science
The latest series of the ABC Radio National podcast #CosmicVertigo is out and we're taking things to the EXTREME. I have to say I have the most fun with Dr Amanda Bauer recording these, they're made for your listening pleasure so I hope you enjoy it as much as I do... subscribe where you get your podcasts. Rate and review etc.
However this time you can also ask us questions online or by email (especially if you record them!) and we'll feature the best (or at least the ones I can answer) on the show. Enjoy!Read More
It's truly a remarkable thing to get to present your research to the Assistant Minister for Science, Jobs and Innovation Zed Seselja alongside fellow scientists in ecology, quantum computing and mining... this is what makes Science Meets Parliament such a unique experience and one I'm proud to have assisted as an executive of Science & Technology Australia.Read More
This is a great honour (and also a fun award title!) to be one of Victoria's 2017 Tall Poppies, an award recognising up and coming scientists for their research and efforts to translate this into the public domain. I have to say I felt humbled to be alongside colleagues investigating new solar technologies, cancer treatments and more!
That I got to celebrate it with the two Sarah's in my life (my boss and my wife!) was a real thrill for me.Read More
It was a very special evening spent celebrating the 21st Birthday of Lateral Events, they of the L'Etape Australia / Brian Cox / Sir David Attenborough speaking tour fame. If you can judge a person by the company they keep then you can certainly judge this company by the people they invite! I was able to bore everyone from ABC's MD Michelle Guthrie, Ray Martin, Adam Spencer, Lateral CEO Simon Baggs too the host Prof Brian Cox himself. A wonderful evening that I am incredibly happy to boast of, especially as the wines were selected by none other than the Queen's wine advisor herself Jancis Robinson!Read More
"Dark-ages reionization and galaxy formation simulation VIII: Suppressed growth of dark matter haloes during the Epoch of Reionization" - Qin et al. (2017)
This is a spectacular study by my Yuxiang Qin, one of my PhD students I am fortunate to co-supervise with Dr Simon Mutch and Prof Stuart Wyithe as part of DRAGONS. In this work Yuxiang compares the growth of dark matter structures in the early universe both with and without the impact of gas physics (in particular the fact that giant clouds of atoms have a pressure that prevents them collapsing unlike dark matter). Most simulations ignore that effect to save computational time. Yuxiang showed that's potentially a disastrous step for first structures where the gas prevents the halo from collapsing and through its gravitational pull can also slow the collapse of dark matter itself meaning simulations that take a computational shortcut can produce early haloes that are far larger than they should otherwise be.Read More
I loved making this short ABC ME series with the wonderfully talented and ever enthusiastic Grace Koh trying to explain the answers to questions that we all think of, while restricting ourselves to a green screen and about 3 minutes in total. You can watch all 5 episodes on iView or catch them as interstitials between your favourite shows on ABC ME. Also who doesn't love a big red button?!Read More
Todd Sampson is insane. There. I said it. I understand physics, I trust 100% in the universality of the laws we explore in Life on the Line, but I certainly don't have 100% trust in the engineering. In episode 3 we discuss Friction by throwing Todd off a bungee jump without it being secured (simply interleaved pages of a phonebook). The principle of geometric amplification of the friction means that these phonebooks won't slip by. Everything else however could go wrong. In episode 4 we discuss Conversation of Energy by using a one tonne wrecking ball. This actually DOES go wrong. Yet still he risks his life. I love Todd's trust in my calculations, I just wish he wouldn't actually put his Life on the Line with them.Read More
Awesome. In the truest sense of the word. How else to describe Stargazing Live? A national science extravaganza that involved the great on screen scientists of our age (Prof Brian Cox, Prof Chris Lintott, A/Prof Lisa Harvey-Smith) explaining the latest science from the gorgeous Siding Spring Observatory. I was a permanent panel member trying to answer the public's questions on the Back to Earth show that followed Stargazing each night. The public were asked to help us find alien worlds using Exoplanet Explorer, by the of the three nights Brian was able to announce a world with four super-Earths all closer in than Mercury... Insane. I still can't understand how it formed. Truly one of the most incredible experiences I've ever been part of, thanks Stargazing!Read More
I've been involved in some mammoth science communication events, and I firmly believe to ensure the role of STEM in our society we need these huge shows to make science cool again. I shared my thoughts on this and alarming decline in STEM enrolment rates on theconversation.Read More
The new ABC Radio National science podcast hit the airwaves and I cannot be prouder of this show. Alongside my rantings is the insightful, measured yet ever enthusiastic explanations of my friend and co-star Dr Amanda Bauer. The entire series is run by the ABC's astoundingly talented producer Joel Werner. Subscribe and have a listen wherever you get your podcasts (iTunes).Read More
"Dark-ages reionization and galaxy-formation simulation VII: The sizes of high-redshift galaxies" - Chuanwu et al. (2017)
A lovely prediction paper from Chuanwu Liu of the DRAGONS collaboration showing the expected sizes for the most distant galaxies that current (and future) telescopes are trying to observe. The tentative existing detections appear to be well explained by our model of galaxy formation with the effective radius (i.e. the size of the disk of the galaxy) being larger for brighter objects but only with a power law scaling of 0.25! In other words a galaxy ten thousand times more luminous will be a disk galaxy only ten times wider. Finally, we make clear that the successor to the Hubble Space Telescope (the James Webb Space Telescope) will be unlikely to see these tiny disks and instead we will have to wait for ground based extremely large telescopes like the Giant Magellan Telescope (and critically one in which Australia is heavily invested).Read More
Super bizarre but cool honour to find myself featured in Qantas Magazine! I travel ridiculous amounts for work and find myself flicking through this mag on take off and landing, never thought I'd be reading about myself! Thanks iQ for uncovering my secret shame that I am rubbish with DVD players.
As you can tell I was a little excited about seeing myself at the end of an international flight in the Spirit of Australia inflight magazine..!Read More
So this is absurdly cool, the Chief Scientist has named me as one of Australia's Science Superheroes... I honestly can't claim this (and especially not when you see the other superheroes) but it gave me a chance to answer some fun questions about what my 'superpower' in science actually is.
How do you become a superhero scientist? Well firstly you don't need to get bitten by a radioactive (and very smart) spider instead during National Science Week in August 2016, Australia’s Chief Scientist launched the #5ScientistPledge to recognise Australian Scientists. Those scientists are now getting recognised with a new tag – #AusScienceHeroesRead More
"Dark-ages reionization and galaxy-formation simulation VI: The origins and fate of the highest known redshift galaxy" - Mutch et al. (2016b)
The recent discovery by Oesch et al. (2016) of a far-off galaxy seen just 400 million years after the Big Bang but already having accumulated a billion Sun's worth of stars was considered a bizarre object. Yet the simulated DRAGONS universe apparently contains several analogues as shown in this beautiful work by my colleague Dr Simon Mutch. We show that such a monstrously oversized baby galaxy is possible if it grows rapidly but consistently throughout time and not as a result of cannibalising neighbouring objects through galaxy mergers as is oft suspected.Read More
My regular column in theconversation (as well as appearance on ABC Breakfast News) explored a Thanksgiving meal that was out of this world, as well as the beginning of the end for the Cassini mission (but not without a spectacular final view) and a new fuel-less rocket that set the internet alight might be a misfire after all.Read More
"Dark-ages reionization and galaxy formation simulation V: morphology and statistical signatures of reionization" - Geil et al. (2016)
A key goal of the DRAGONS investigation was to predict how growing galaxies in the early universe would ionise the neutral hydrogen around them. This is the long-sought after signal of Reionisation (also known as Cosmic Dawn) when the Universe was filled with light, lifting this dark opaque fog. It is the target for telescopes like the Square Kilometre Array to characterise that early universe when ionised bubbles of gas around the galaxies resembles a swiss cheese model. This beautiful work by Dr Paul Geil calculated how our simulated galaxies would impact that material around them finding that the galaxy formation that resulted in the biggest impact was the nature of how stars exploded. This both ionised gas around it but more importantly limited how new stars could form and hence limit the amount of ionising radiation and therefore the size and number of the ionised bubbles. This is however not a unique signature and instead even when we find the swiss cheese universe we have a lot of work ahead to tease out its lessons. Depressing but beautifully analysed science by Paul.Read More
"Dark-ages reionization and galaxy formation simulation III: Modelling galaxy formation and the epoch of reionization" - Mutch et al. (2016a)
A mammoth effort by my long-time collaborator Dr Simon Mutch explaining the semi-analytic model Meraxes that `paints' the galaxies onto the background dark matter structures formed in the huge simulated DRAGONS universe. This work has so many critical lessons on key physics that grows a galaxy that matches what we see in the distant universe (and hence seeing those objects as they were long ago when the light first left them). Perhaps the key is that the fraction of energetic light that can escape forming galaxies (and hence ionise the neutral hydrogen atoms in the vast distances between them) has to increase towards earlier times. Somehow galaxies trap evermore of this radiation as they grow up. A mystery that we will hopefully solve in this series of works!Read More
"Dark-ages reionization and galaxy formation simulation - IV. UV luminosity functions of high-redshift galaxies" - Chuanwu et al. (2016)
The first paper by Chuanwu Liu in his PhD with DRAGONS showed that we can explain observations of distant galaxies glowing in ultraviolet (UV) light. This light is responsible for ionising the neutral hydrogen between the galaxies, ending the Cosmic Dark Ages in a process known as Reionisation. Chuanwu's work showed that our simulated galaxies can recreate the current observations, but that we can then predict what future observations may see as our simulations form much smaller objects at this time than even Hubble can find. The main finding was that dwarf galaxies are responsible for providing most of the ionising radiation that lights up the universe; in agreement with my entirely complimentary and independent technique in Duffy et al. (2014b). Promising start to your academic career Chuanwu with such a careful and expansive analysis on this hot topic!Read More
I got to indulge my twin passions, science and science fiction, in this talk for Swinburne's Open Day. One day I hope to record a more polished, full length talk, for now this is a great 'best-of' compilation by the team.Read More