Comments on: More on NGC 1316

By: SF Reader

SF Reader — Tue, 28 Nov 2006 16:22:34 +0000

As an add-on to Gary’s idea, what do the jets from the core black hole do to stars in their path? Are those SNs in that path, perhaps?

It’s clearly been going on for quite some time, given the size of the plumes.

By: lamacher

lamacher — Thu, 23 Nov 2006 21:52:46 +0000

Brings up a question: does anyone know what the killing range for a SN is? For eg, if Betelgeuse at 500 LY or so has already blown up, what is the outlook for this solar system?

By: Mungascr

Mungascr — Thu, 23 Nov 2006 14:09:03 +0000

Yep, its an unusal galaxy alright but it does (as someone here already mentioned) remind me quite a bit of Centaurus A (Which also has an NGC designation that I can’t recall from the top of my head.)

I wouldn’t be rude about a galaxy that was so exceptional and showing such generosity with its supernova displays Phil!

I’d say it was a standout or exceptionally cool galaxy rather than a weirdo and as for the er..crud … it swallowed and ejected I think there are better ways you could phrase it.

After all we don’t want to hurt its feelings do we???

By: tacitus

tacitus — Thu, 23 Nov 2006 03:40:42 +0000

Carl, interesting comments. As I mentioned in my previous comment, I would think that the supernova scenario would only be practical if the civilization had spread over an appreciable amount of the host galaxy. In that case, the use of a few thousands of stars in this manner, or even a million or two, in parts of the galaxy far enough away from the inhabited areas.

And it likely would only happen if the civilization had exhausted other avenues for detecting and communicating with other intelligent life in nearby galaxies. If civilizations are really so rare that only a small percentage of galaxies are host to a single successful intelligent species (I think not likely, but it’s possible) then what better way to advertise your presence than to light a few beacons that can be seen from half-way across the Universe?

Sure it would be a long shot, but if you’ve accomplished everything else as a civilization except make contact with another, then I suspect you might go to extraordinary lengths trying.

I agree it’s not likely, but you never know….

By: ioresult

ioresult — Wed, 22 Nov 2006 22:11:16 +0000

All this reminds me of the Known Space sci-fi universe of Larry Niven where the center of our own milky way is undergoing a chain reaction of catastrophic supernovae. The shockwave will reach the ficticious Earth in 20k years. I’m wondering what could possibly cause such a chain reaction… a supergiant black-hole merger creating a gravitational shockwave that would precipitate the collapse of surrounding stars? Wow, such imagination!

By: ioresult

ioresult — Wed, 22 Nov 2006 22:07:08 +0000

PeterV, dust is heavy elements created in previous supernovae. I think the generic term refers to a mix of light gaseous elements and solidified grains made of condensed heavy elements. In any case, “dust” is only visible because it absorbs light, so it appears dark against a bright background. A young galaxy is still full of dust and gas, but an old galaxy has seen all its dust condensate in planemos (planets not orbiting any star), brown dwarfs or red dwarfs.

So, other people, do I get it right?

By: Carl R. Sams

Carl R. Sams — Wed, 22 Nov 2006 21:19:00 +0000

tacitus-

While the idea of detonating super-nova sounds technically possible for a greatly advanced civilization, it would also seem like such a waste. Assuming the c=top speed rule, then these stars are going to be the greatest source of energy in a civilizations immediate area, and therefore any civilization able to blow up stars is likely to be harnessing them for energy ,Type II civilizations on the Kardashev scale. It would be analagous to us gathering all the fosil fuels on Terra, putting them in one spot, and lighting the mother of all signal fires “just in case”. Gonna go with probably not on this one.