Tag Archives: astrophysics

Is cosmology in crisis?

In past posts, when I’ve written about the expansion of the universe, I’ve generally referred to the rate of that expansion, the Hubble constant, as being around 70 km/s/megaparsec, that is, for every megaparsec a galaxy is distant from us, … Continue reading

Posted in Zeitgeist | Tagged , , , , , , | 23 Comments

Dark matter might cause neutron stars to collapse into black holes

ratamacue0 called my attention to this interesting article on the possibility of dark matter “eating” neutron stars: Dark matter: Devourer of stars | Ars Technica. Neutron stars are collapsed stars that have used up all of their fusion fuel.  Typically what happens … Continue reading

Posted in Zeitgeist | Tagged , , , , , , , , , | 6 Comments

The movie ‘Interstellar’ and wormholes

The other day, I did a post on interstellar exploration which linked to one by Sten Odenwald on the problems with interstellar travel.  Well, he posted some follow-up remarks, expressing some surprise at the response, doubling down on the aspects of the limitations of … Continue reading

Posted in Zeitgeist | Tagged , , , , , , , , , , , , , | 9 Comments

Ask Ethan #12: How far is the distant Universe? – Starts With A Bang

Ethan Siegel’s blog, Starts With a Bang, is one of the best science astrophysics blogs on the web. Ask Ethan #12: How far is the distant Universe? – Starts With A Bang. In this post, he tackles an issue I … Continue reading

Posted in Zeitgeist | Tagged , , , , , , , , , , , , | 1 Comment