Little, Big

interesting pair of stories on black hole discoveries

ok, so they're like so totally last year...
I'm trying to catch up

RXTE finds low mass black hole - claim it is just under 3 solar masses
intereting to contemplate how it came to be
well, either that or the object is further away or more luminous than previously thought

the other story is the Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies. claim
Most excellent.

Many years ago I was a co-author on a fun little paper where we postulated some interesting little effects IF ultramassive black holes (order 10¹⁰ solar masses) existed, noting OJ 287 as a candidate example.

Years later, at the ACP, my co-author presented a revised estimate on probable maximum masses of central supermassive black holes in collaboration with a student.
They picked out particularly good candidate objects, one of which is among those where ultramassive black holes have been found.

I remember this well, having discussed the possibility of ultramassive black holes, in this context, at an ACP meeting, giving a short inforal talk on it - and being told by a number of observers that it was silly, though I know at least one group applied for HST time to look at cD galaxies... don't think they go it, premature.

In either case, it is nice to see a theorist's prediction come true.