How powerful would a explosion or other destructive force have to be to destroy a entire galaxy?

Question

In the well known and popular game Halo the aliens called the covenant have a massive planet sized weapon that's called a Halo that's capable of destroying a entire galaxy the weapon even had it's own gravity and atmosphere. The covenant had the weapon as a last resort defense against the zombie outbreak known as the flood that has been spreading across the galaxy. The covenants logic was if they destroyed everyone and everything the flood would deteriorate and eventually be wiped out due to having no food source or anyone around to turn into one of them. Obviously the humans had a problem with that plan believing the flood could be stopped without having to just kill everyone and it is part of the reason why the humans and the covenant are at war. The first of the Halo games has a large portion of the game on the Halo as you are doing what you need to do to destroy while the covenant troops are trying to stop you.

So I was curious how strong would that Halo actually have to be if it really was capable of destroying the galaxy?

Red · Answer

There isn't really a scale for expressing the kind of force required to destroy all matter in a galaxy in a single event. Aside from the Big Bang, humanity has never encountered or discovered a force even a fraction of what you're asking. Stars explode, yes, but those can only damage the surrounding celestial bodies in their system, such as planets, moons, gas giants, et cetera. Galaxies, however, contain hundreds of billions of stars and systems. Even if the largest known star were to go hypernova, the damage/disruption it would cause to its home galaxy would be so inconsequential that it might as well not even have happened.

? · Answer

No such force exists, except for the universe itself....it is said the universe exploded to begin and has been expanding outward ever since.....it is also said that perhaps like some elastic being expanded it might one day reach its limit and come snapping back and destroy everything that it created in its expansion.

Other than that the only real threat to a galaxy is another larger galaxy consuming it. and devouring, which experts say is the fate expected for our galaxy someday.

Anonymous · Answer

I thought it just killed all life, not destroy planets.

Hombre Sin Nombre AKA Oggmeista · Answer

not exact but i think the only answer here given the relative magnitude of this question would be

Grahams number  to the power of grahams number

and if that's not big enough

infinitely powerful....which is a hyperbole in itself because just by saying +1 to it you immidiatly create a bigger number =?
∞

my problem is though

how do you destroy space?,  space is a vaccum  ie it contains virually nothing ,as well as obviously all the celestial objects,.., how is anything supposed to destroy that?

Ender772 · Answer

well the weapon is a cirlcle of these things and not just the one itself. and all it did was emit radiation.

? · Answer

The most explosive force after the Big Bang is when a supermassive star explodes as a hypernova. They’re between ten to one-hundred times more powerful than a supernova.

All galaxies get hypernovae, and even though they are very destructive locally they have as much effect on their host galaxies as popping a simple zit on a human being. They’re not even totally destructive: the pressure waves they send out and the materials they eject directly cause new stars to form.

So the galaxy-busting weapon in Halo is purely fictional and would not be possible due to the limitations of physics.

Anonymous · Answer

Very, very, very powerful

How powerful would a explosion or other destructive force have to be to destroy a entire galaxy?

7 Answers