A rather brilliant paper from my student Mitchell Dixon focussed on exploding stars, known as supernovae, and finding ways to make them more accurate distance measurement tools to map the expansion of the universe itself. In the end he found that nearby ‘calibrator’ supernovae had a systematic shift with the specific star formation rate (i.e. how rapidly the galaxy is doubling its mass in stars) and taking that into account he improved the accuracy of the expansion rate of the universe known as the Hubble Rate (or H0 of the title).
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Our Universe is expanding, and indeed accelerating in that expansion, and primary means to that discovery last century was measuring the apparent brightness of exploding stars known as supernovae. A special kind of supernova explodes at (almost!) the same brightness, known as Type 1a, and hence if you measure that brightness you can figure out how far away they are relative to each other. My student Mitchell Dixon published an exhaustive analysis of how to better calibrate that brightness of the Type 1a supernovae, in particular showing that they depended on the dust in the galaxy (slightly dimming them, or else perhaps causing a slightly different explosion brightness).
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I got a little carried away with the ridiculous scale of the latest explosion in space, outshine the entire Milky Way twenty times over. We have no idea how to produce this level of explosion. Then there was brief chat about SpaceX and its unfortunate crash on a sea barge then a final rant about the wonders of Pluto!
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The Project invited me on the show to chat about an astounding discovery... A new tiny faint point of light appeared in the sky, 10000 times faint than could be seen by the naked eye, but when we realised it was 3.8 BILLION lightyears away it was clear that it must be astoundingly bright to even reach this faint level. This was the brightest supernovae ever recorded - ASAS-SN-15lh
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