Quasars

Quasars - Have you heard of them before? These massive objects put off so much energy that current physics models can't explain how it is possible for them to exist.

A quasar is actually the result of accretion of matter around a supermassive black hole. Most black holes are virtually invisible, this is because light cannot escape if it gets too close to the black hole. A quasar has a mass of material that remains above the event horizon (the point of no return). This material is subjected to unimaginable forces from the black hole. Essentially, the matter is torn apart. A black hole literally rips matter into pieces.



The most luminous quasars radiate at a rate that can exceed the output of average galaxies, equivalent to two trillion suns. That is (2×10¹²) times brighter than our own sun! These objects are so massively bright they outshine stars billions of light-years closer. It is completely impossible to even grasp how bright these objects are.

To help you try and grasp the magnitude of these objects, here is a list:
(A Joule is a standard unit for measuring energy, a single joule isn't a whole lot)

An apple dropped 2 feet	1 Joule
A 10 Watt flashlight left on for 1 minute	600 Joules
Energy from firing an Elephant rifle	7,000 Joules ~ 7 Kilojoules
Accelerating a 4 ton (8000lb) car to highway speed (55mph)	1,200,000 Joules ~ 1.2 Megajoules
Energy in average lightning bolt	1,000,000,000 ~ 1 Gigajoule
Energy released by an average hurricane (per second)	600,000,000,000,000 ~ 600 Terajoules
Energy released from the Tsar Bomba (the largest nuclear weapon ever detonated)	210,000,000,000,000,000 Joules 210 Petajoules
Energy from the sun that the earth receives every year	5,500,000,000,000,000,000,000,000 Joules 25 million Tsar Bombas or 5.5 yottajoules
Total energy released by the sun every second	380,000,000,000,000,000,000,000,000 Joules 70 times the amount energy we receive from the sun annually

Now, the amount of energy released by a Quasar is: 750,000,000,000,000,000,000,000,000,000,000,000,000,000 Joules
Every. Single. Second. Because such large numbers are hard to comprehend, let me break that down further. The amount of energy released is equivalent to 2 quadrillion of our suns. Our milky way galaxy has an estimated 200 - 400 Billion stars, however, our sun is significantly brighter than the average star. Our milky way galaxy has an estimated output of around 5*10^36 Joules.

The energy output of a quasar is roughly equivalent to the energy output of 150 thousand galaxies.

Think about that.

Freakin' Awesome.

Magnetic Fields

An electromagnetic field is produced by any charged particle, and extends indefinitely throughout space. This force is one of the four fundamental forces of nature, with the other three being gravity, the strong force and the weak force. The Earth acts like a massive charged particle, with a field that encompasses it entirely. The core of the Earth creates this powerful field. The Earths negatively charged pole is located around the geographic north pole, and the positively charged pole at the south pole.
One of the most important thing the field does for Earth is that it shields us from solar wind. Solar wind is a stream of charged particles that come flying off from the sun. Without this protection the surface would be not a very habitable place.

Solar wind

The field is responsible for the northern lights. The northern lights are commonly seen in the latitudes between 60 and 72 degrees north and south, just within the Arctic and Antarctic polar circles. The light is created by collisions of charged particles created by the magnetic field. The light is usually created in the ionosphere, about 80km (50 miles) up.

Climate Change

While not a space topic, i think everyone could do with a bit more informing on this topic.

Click for full-sized image.

I'm not going to try and sway you one way or another. You can draw your own conclusions from these pictures.

Titan

Titan is a cold moon in orbit around Saturn. Titan is the largest moon in orbit around Saturn, slightly larger in size to the planet mercury. Titan is the only other celestial body in the solar system that has liquid oceans. But these oceans are not water, they're methane so cold they have condensed into a liquid state, evaporating and falling again as rain. The satellite experiences much the same forces as Earth with wind, and weather patterns.

Composite view of Titan built with Cassini images

"It has also been suggested that a form of life may exist on the surface, using liquid methane as a medium instead of water; and anomalies in atmospheric composition have been reported which are consistent with the presence of such a life-form, but which could also be due to an exotic non-living chemistry"  -Mckay, Chris (2010). "Have We Discovered Evidence For Life On Titan"

The gravity on Titan is only 14% of that on Earth. Titan is the only known moon with a fully developed atmosphere that consists of more than just trace gases.
If you were on Titan, you could fly.

Theia

A colossal interplanetary collision doesn't sound like a good thing.

But when Theia collided with Earth 4.5 billions years ago, it resulted in a satellite that is anomalously big in comparison to its parent planet. There is nothing else like it in the solar system, where satellites are relatively small bodies that either accredited slowly from orbiting debris or were captured in passing. Elsewhere it seems a similar story. Giant collisions in other solar systems would produce abundant dust visible to the infrared Spitzer Space Telescope, but although a few such dusty systems have been found, collisions big enough to produce something like the moon seem to happen in only 5 to 10 per cent of solar systems - with the number of instances where this has actually happened considerably smaller even than that.

Why does this matter? Because the moon's size provides a steadying gravitational hand that helps to stabilise the tilt, or "obliquity", of Earth's axis. That prevents wild changes in the pattern of solar heating on the planet's surface that could lead to extreme climate swings, including frequent periods where the whole planet freezes over. That's a big deal for us. Conditions might be bad for complex land-based life if there were no moon and obliquity varied significantly.

more space info to come, and pictures.