We actually only looked at 100 of the over 2,000 galaxies in Virgo. Also, the field of view of the camera we were using (the Advanced Camera for Surveys) is sufficiently small that for large galaxies like M87, we only measure a fraction of the total population of globulars. We know from other observations and that M87 has ~13,000, but we only directly observed around 1,000 with HST.

Keep up the good work!

I always thought we (the Milky Way) were part of the Local cluster, or the Local group, wich in turn was part of the local supercluster, or the Virgo supercluster.

Me too.

So, to the experts – what is wrong with that picture?

Im sorry…black holes evaporate? does anyone have proof to substantiate this?

Um, we had that question a few threads back. It comes out of GR research in the 70′s.

I’m not conversant with GR. But AFAIU there are two ways that black holes may loose energy on, and so evaporate.

The first way is to extract mass-energy from excited black holes. (Black holes are dynamic objects with mass, momentum, angular momentum and charge.) Let me cite the old GR bible (“Gravitation”, Misner, Thorne, Wheeler; also called “MTW” for short):

“A Kerr-Newman black hole – which is rotating or charged or both – is not dead. The rotational and electromagnetic contributions to the mass-energy can be extracted.”

So first you have the gravitational radiative dynamics of a freshly collapsing black hole. Then it starts to stabilize it can continue to leak off energy as a Kerr-Newman black hole by being perturbed by the environment, say an accretion disc, until it is a “dead” Schwarzschild (non-rotating, non-charged) black hole.

The second way is through Hawking radiation, which Hawking established as a possibility by physics, not by “say so” obviously. I assume string (brane) models can give the same results. And finally I assume that the final evaporation of black holes are not well understood. (That, I believe, is one of the uncertainties of LHC detection of the same.)

I believe none of these ways are experimentally proven by direct observation. But there are ongoing attempts to use optical systems to simulate the event horizon of black holes to possibly observe analogue processes.

But: The particles in the jet are not massless. You can have electrons, protons, positrons, etc in such a jet with incredibly high speeds – as I said before, they are very closed to the speed of light. The particles do NOT come OUT of the black hole but from it’s accreation disk. But how they are accelerated to such speeds is still a mystery, as I also said before.

My head hurts.

Hawking Radiation was it? someone correct me if I’m wrong.

/P

Basically, word for word, in order, it translates, “Man sees the forest through lots of trees not.”

Simple. That material was never inside the the “tremendous gravity” represented by the black hole’s event horizon: that ionized gas in the jet comes from the extremely energized accretion disk immediately surrounding the black hole.

Thank you! More stunning photos and text.

The Virgo Cluster is too big for me to comprehend. And, the universe is bigger.

Um, with all that energy spewing out of its center, wouldn’t that preclude life as we know it, on any planets with the stars of M87? That flare has to be awesome, to look that big from this far away. Really mind boggling.

So, I’m seeing a discrepancy between the two descriptions. In yours, it’s 11,000 GCs in a cluster of 2,000 galaxies, and in the space telescope page, it says 13,000 GCs in M87 alone, which, if true, is mind-blowing. Could you clarify?

Incidentally, I saw my first cluster when I was researching for a play that I worked on which had an astronomer as its main character. Unfortunately, the playwright was not an astronomer, so the science was a bit off. But the cluster was amazing beyond words.

I always thought we (the Milky Way) were part of the Local cluster, or the Local group, wich in turn was part of the local supercluster, or the Virgo supercluster.

How do you mean, “not really part of”?

Bear with me people, I’m less than a layman when it comes to astronomy, tho it’s been an interest of mine since I was a kid.

/P

Phil, I know you’re not getting paid for this, but couldn’t we have better numbers? Otherwise you might as well just post pictures and say “ooh, pretty” and “James Randi makes my heart thump ironically!!!”.

‘Cuidado, porque puede ser que los árboles no te dejen ver el bosque’
Cuidado, porque puede ser que los árboles te maten al caer encima

Within the constellation of Virgo (an arbitrary chunk of sky) exists a supercluster of galaxies. Because the supercluster is mostly in the part of the sky we call Virgo, it gets called the Virgo Supercluster.

Besides, it is interesting to point out that galactology would be ‘the science of milk’!