This really is a brilliant time to be an X-ray astronomer. Launched on 13th July 2019 on board the SRG spacecraft, the eROSITA X-ray telescope has completed its first full sweep of the sky, mapping more than a million energetic objects and so roughly doubling the number of known X-ray sources discovered since the dawn of X-ray astronomy some 60 years ago. Continue reading “eROSITA’s new X-ray map of the Universe”
TIDK = Things I didn’t know. What I didn’t know until I started gathering the knowledge that in another lifetime may have made me a professional astronomer. This may turn out to be a long list…
I knew that neutron stars were stellar remnants, leftovers of stars that had finished with nuclear fusion and collapsed under their own gravity to the point where protons and electrons were crushed together to create more neutrons to join those that were there already. So my answer would have been “neutrons” whether you had asked me “what’s the surface made of?” or “what’s the centre made of?”. Neutrons all the way down and through. Continue reading “TIDK #1 – Neutron star interiors”
For the detail behind the content of this post see “Neutron Star Radius-to-Mass Ratio from Partial Accretion Disc Occultation as Measured through Fe Kα Line Profiles” as submitted to ApJ by Riccardo La Placa et al, March 2020. Continue reading “Prospective method of measuring neutron star radius/mass ratios”
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