Neural Delight

The Solar Eclipse from space

Greeted by a Triangle of light. Taken by Neural Delight

Sunlit greens

Hu la hoopin your problems away

Cuteness Personified - Taken by Neural Delight

Lusciously green.

America’s been a country for 235 years, and at war for 209 years.

A huge storm…..that I want to be right in the centre of. Right now.

In Oct 2010, NASA’s Rossi X-Ray Timing Explorer (RTXE) detected a ton of transient x-rays being burst from a neutron star close to the centre of our galaxy, (the milky way in case you missed the memo).

A neutron star “ is the closest thing to a black hole that astronomers can observe directly, crushing half a million times more mass than Earth into a sphere no larger than a city.”

The x-ray bursts were due to thermonuclear explosions on the star’s surface.

So the story basically begins with what you call an “X-RAY binary system”, which occurs when a donor star ( a star similar to our sun) and an accretor ( in this case a neutron star) which basically sucks the matter right out of donor star, displayed eloquently by this video below:

http://youtu.be/UX1qb5qb_W8

So what happens as the matter is being taken in by the neutron star ( forming an accretion disc), the matter becomes known as “in falling gas”, and this absorption of matter releases gravitational potential energy in the form of electromagnetic radiation ( in this case, X-RAYS).

Shortly after the binary system was detected, it was observed that the neutron star is also a pulsar, and a pulsar is a neutron star that regularly emits electromagnetic energy (X-rays) at periodic intervals.

This particular neutron star was beautifully named TX52.

Since TX52 is the closest thing to a black hole, it also possesses a very strong magnetic field.

The implication of this magnetic field is that it pulls in the falling gas towards its magnetic poles, creating hot spots near the magnetic poles, shown by the following picture:

http://ircamera.as.arizona.edu/NatSci102/NatSci102/images/neu_star.jpg

The hot spots rotate with the neutron star, and since the gravity of the whole situation is extremely dense, the gas begins to coat the star in a layer of Hydrogen and Helium ( the latest in planetary fashion).

So as this H + He coat layer grows, you begin having thermonuclear explosions, which cause the X-Rays.

So the point is, the higher the rate of accretion, the more continuous the thermonuclear explosions because of the rate of gas falling increases, acting to continually provide the fuel for the explosions, via the H + He coat layer, and the continuous stream of x-rays called spikes.

With slower accretion rates, the fuel layer has to rebuild slowly after every massive thermonuclear explosion, giving a short but large spike in X-ray emissions.

The theory that is supported by this particular system, which had yet to be proved by observing 100+ neutron stars over 3 decades, is the theory that

                    at the highest rates of accretion, the x-ray spikes disappear, and what you get are “gentle” waves of emission, which means that this is a marginally stable form of nuclear fusion.

Nuclear fusion is the formation of a new heavier nuclei, via the fusion of two smaller nuclei.

Essentially this is how stars create matter, the same process in which the matter we consist of was formed. But usually this occurs when a star implodes on itself, and thus, its cool to see that such a process occurs without a star having to implode on itself.

The link to the article is here:

http://www.physorg.com/news/2012-03-nasa-rxte-captures-thermonuclear-behavior.html