Various articles about black holes talk about X-rays emitted near the event horizon 'reflecting off the accretion disc'. What kind of material is it that can...

There have been recent cosmological experimental disclosures represented in part by the following: The 7Be(n,p)7Li reaction and the Cosmological Lithium...

I am trying to model surface temperatures on Mars. Coming up with insolation received at the various latitudes was fairly simple, the equations are found at...

A team of astronomers have conducted a search for distant super massive black holes and they have found 83 of them....

The picture from the Event Horizon Telescope: https://apod.nasa.gov/apod/ap190411.html Why is the center black? Does the accretion disk just happen to be in...

Can the recent findings of the Space Telescope Institute be used to revise the age of the universe. What would the estimate of 13.7E9 years become if the...

Not long ago, we had some discussion here of reionization. I've just seen a terrific colloquium by Steve Finkelstein on the subject. It's available...

Consider the following papers: DZ65: http://adsabs.harvard.edu/abs/1965SvA.....8..854D @ARTICLE { VDashevskiiYZeldovich65a , AUTHOR ...

The Million Quasars (Milliquas) catalogue v6.3 is released with data from publications to 15-June-2019, with the count of type-I quasars & AGN up to 623,004. ...

The subject of Martian methane blowouts keeps arising. Assuming that they will be confirmed, is there any way yet on-site or in-orbit, to then measure the...

For a while back in the 1990s, A&A published some things (such as appendices to papers) ONLY electronically. However, ftp://cdsarc.u-strasbg.fr doesn't seem...

Hello! The German astronomer Felix Schmeidler published two works in 1985. "Messung der Lichtablenkung während der Sonnenfinsternis am 15. Februar...

A few weeks ago, fellow moderator Jonathan suggested that I "live-post" from a conference, so I'll do so this week. He was actually thinking about another...

At most of the last few conferences I've been to, including this one,=20 there has been a talk pointing out that primordial black holes could make=20 up most...

There has been much discussion, including some here in this newgroup, regarding the "tension" between various measurements of the Hubble constant. In general,...

The concluding talk on open problems in cosmology was given by Joe Silk. I'll mention below a few things I found particularly interesting. Although the...

Early-type Host Galaxies of Type Ia Supernovae. II. Evidence for Luminosity Evolution in Supernova Cosmology https://arxiv.org/abs/1912.04903 The authors...

A new paper accepted by ApJL, arXiv:2001.04471 "Nonstationarity of AGN variability: The only way to go is down!" by Caplar et al, concludes that visible quasar...

In a number of documentaries i've watched over the years when discussing the fate of the inner terrestrial-planets when the Sun enters its' red-giant phase it...

On an old LaTeX installation, things work fine, with one bug I can correct: the URL gets broken by a % (i.e. to make LaTeX ignore the line break) if it is a...