Questions regarding the Near-Earth Geminga Supernova Event

wildespace
I also find it interesting that this hot diffuse gas in the Bubble emits X-rays.

Yes, that kind of intrigues me too, but I don't pretend to understand what that actually implies. I have a similar interest in radon gas emissions due to the 'x-ray' potential.

Just found this...

Ohio State University astronomers have concluded that there's a probability of almost 100 percent that a star will go supernova in the Milky Way during the next 50 years. The explosion, they said, will be visible from Earth.

'This study suggests that they have a solid chance of doing something that's never been done before: detect a supernova fast enough to witness what happens at the very beginning of a star's demise. A massive star "goes supernova" at the moment when it's used up all its nuclear fuel and its core collapses, just before it explodes violently and throws off most of its mass into space.'

I know, I cheered on my chair too when I read about this in EurukAlert. Then my happiness imploded when I read about the odds of it being visible to the naked eye: only 20 to 50 percent. If you want to have the highest probabilities of seeing it you will have to move somewhere in the southern hemisphere, as you can see more of the Milky Way there. A supernovagasm interruptus.

sploid.gizmodo.com...

Which posits the thought...I think the old article that I linked to suggested that the gas 'bubble' had a limited life span because it was the result of a single supernova event, but as Arbitrageur subsequently pointed out, more recent research has indicated that the 'Bubble' is the consequence of multiple events...am I taking too many leaps to believe that this means that the 'Bubble' is being consistently replenished? And possibly, that the solar system or the 'bubble' itself is acting as a draw for the gases emitted?

KilgoreTrout
Which posits the thought...I think the old article that I linked to suggested that the gas 'bubble' had a limited life span because it was the result of a single supernova event, but as Arbitrageur subsequently pointed out, more recent research has indicated that the 'Bubble' is the consequence of multiple events...am I taking too many leaps to believe that this means that the 'Bubble' is being consistently replenished? And possibly, that the solar system or the 'bubble' itself is acting as a draw for the gases emitted?

The local bubble isn't really even shaped like a bubble. David Darling says it's more hourglass shaped but I'm not even sure about that description after looking at the diagram on his site. However the shape is consistent with his idea that there may be more than one supernova involved in its creation, in my view:

www.daviddarling.info...

Map of the cold, dense interstellar gas surrounding the Local Bubble in the plane of the Galaxy. White areas represent regions of extremely low gas density (which are probably filled with plasma); dark areas reveal where large condensations of cold, dense gas occur. Notice that the local cavity is surrounded by many of these condensations, but this "wall" is broken in several places by low density interstellar tunnels that link the local cavity with other nearby bubble cavities such as the Pleiades and GSH 238+00+09.

The "Bubble" may be a misnomer since it appears to have an hourglass shape that is narrowest in the galactic plane and that widens above and below the plane. In fact, in directions away from the galactic plane the Bubble appears to be opened-ended, bursting into the galactic halo, so that "Local Tube" describes it better. Inside it are numerous cloudlets, oriented in sheet-like structures near the Bubble's boundary. The Sun, along with several neighboring stars, is presently embedded in a group of such cloudlets, known as the "Local Fluff Complex" or, more prosaically, as the local interstellar medium (LISM), that is passing through the Local Bubble. These floating islands of neutral hydrogen atoms have resulted from the expansion of an even larger bubble, the Loop I superbubble, up against our own cavity. The Loop I superbubble was created by supernovae and stellar winds in the Scorpius-Centaurus Association, which lies about 500 light-years away. When the Local Bubble and the Loop I collided, the Local Fluff Complex formed at the boundary between the two. This boundary lies 50 to 130 light-years away and through it the cloudlets are invading our Local Bubble. The Sun lies very close to the edge of a cloudlet named the Local Interstellar Cloud and is moving roughly perpendicular to it.

He says "local tube" is a better description, but whatever you call it, there seems to be a lot more going on than a single bubble.

And yes it's believed these low density bubbles may be "short lived" in cosmological terms, meaning they can last up to millions of years. But as for being "consistently replenished", yes I think that's a bit of a leap. I think it might be a little more accurate to hypothesize that clouds or nebulae (like the one in my avatar) can form stars in a localized area, that some of those stars can be large enough to ho supernova eventually forming a series of bubbles, but I wouldn't really imply "continuously" in that, as it seems more like a "life cycle" of a stellar nursery. I'm not sure we understand all the details of that life cycle but we can see certain aspects of it, again like the young stellar nursery in my avatar, and we can apply the laws of physics we know to try to predict what will happen to it, like forming more stars that will eventually die in supernovae and create bubbles, but it won't do so "continuously" as there is only a finite amount of material present in the nebula from which to form stars.

I wonder if this could be the cause of Earth's periodic ice-ages that have been observed from ice-core samples. There are some theories that it is due to the orbital inclination and eccentricity of the Earth. But wouldn't there be traces of dust and other supernova byproducts in the core samples?



en.wikipedia.org...

stormcell
I wonder if this could be the cause of Earth's periodic ice-ages that have been observed from ice-core samples. There are some theories that it is due to the orbital inclination and eccentricity of the Earth. But wouldn't there be traces of dust and other supernova byproducts in the core samples?

I believe that one of the ways of testing for near Earth supernovas is by checking Nitrogen oxide levels in ice cores, that seems to be seen as a possible 'signature' of these events. In terms of them effecting the Earth's tilt, I don't know. I presume that the blast of the explosion would have to be in much closer proximity if it was to have any such effect, but really, in all honesty, I don't know anywhere enough about it. However, in terms of ice-ages, there are numerous contributory factors to glaciation, tilt being just one of them. For example, our current climate, including the preceding major glaciation, was facilitated by the North American, South American and Caribbean plates moving towards one another, forming the Isthmus of Panama which prevented the mixing of the Pacific and Atlantic Oceans, creating a notable difference in salinity which facilitated the Ocean Conveyor, in combination with the Trade Winds, in drawing weather systems to the Northern Hemisphere which brought fresh water precipitation. This then combined with a tilt, around 3 million years ago, helped bring about the ice age. But other factors were involved, as they are now, including human activity.