Astrojohn

Now loaded on arXiv.org Cornell University Archive.

1. arXiv:2206.06919  [pdf, ps, other]  astro-ph.SR astro-ph.EPEclipse timing variations in post-common envelope binaries: Are they a reliable indicator of circumbinary companions?
2. Authors: D. Pulley, I. D. Sharp, J. Mallett, S. von Harrach
3. Abstract: Post-common envelope binary systems evolve when matter is transferred from the primary star at a rate that cannot be accommodated by its secondary companion. A common envelope forms which is subsequently ejected resulting in a system with a binary period frequently between 2 and 3 hours. Where circumbinary companions are predicted, it remains unclear whether they form before or after the common en…
4.  ▽ MoreSubmitted 14 June, 2022; originally announced June 2022.Comments: 16 pages, 8 figures, 7 binary systems and 163 observations

Living just south of Gatwick Airport in a dark sky area still has some challenges.

I have missed another night of binary star measurement due to interference from Starlink.

This is one of my favourite galaxies. Just did a quick exposure after doing some adjustments on my telescope.

Nice plot of the light curve for HS0705+6700, 2.3hr, post-common envelope eclipsing binary system. Spectroscopy and light curve analysis indicated that the secondary companion was a low mass red dwarf star with mass and radius of 0.13M₀ and 0.19R₀