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Today we’re chatting about a kilonova (aka a neutron star merger), that’s SPHERICAL. Our simulations & models show us that kilonovae should throw out material in a donut/disk shape. So this doesn’t make any sense to us. Let’s chat about how we know this and what could explain it…

Sneppen et al. (2023; a round kilonova remnant) - https://arxiv.org/pdf/2302.06621.pdf
Tanvir et al. (2013; suspected kilonova with GRB) - https://arxiv.org/pdf/1306.4971.pdf
LIGO collaboration (2017; expansion rate measurement with GW170817) - https://arxiv.org/pdf/1710.05835.pdf
JWST proposal 1936 - https://www.stsci.edu/jwst/phase2-pub...
JWST proposal 1984 - https://www.stsci.edu/jwst/phase2-pub...
JWST proposal 2091 - https://www.stsci.edu/jwst/phase2-pub...
Troja et al. (2022; the last kilonova detected) - https://arxiv.org/pdf/2209.03363.pdf

My previous videos on the “Crisis in Cosmology”
   • The current crisis in Cosmology - it ...  
   • How we plan to solve the "Crisis in C...  
   • Hubble is fixed! And is the crisis in...  
   • Is the strength of gravity really CON...  
JWST has made the crisis in cosmology worse? -    • JWST just made the "Crisis in Cosmolo...  

00:00 - Introduction
00:25 - Neutron Stars 101
01:06 - What is a kilonova?
02:08 - The first kilonova: GW170817/AT2017gfo
04:01 - Our models predict kilonova are donut shaped - why?
05:49 - The spectrum published this month - what’s a spectrum?
07:18 - Fitting models of the kilonova shape - it’s SPHERICAL?
09:48 - Ideas for why it’s spherical and not donut shaped
11:19 - What’s next?
11:53 - AD: Brilliant
12:59 - Bloopers

Video filmed on a Sony ⍺7 IV

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👩🏽‍💻 I'm Dr. Becky Smethurst, an astrophysicist at the University of Oxford (Christ Church). I love making videos about science with an unnatural level of enthusiasm. I like to focus on how we know things, not just what we know. And especially, the things we still don't know. If you've ever wondered about something in space and couldn't find an answer online - you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.


http://drbecky.uk.com
https://rebeccasmethurst.co.uk