It All Started with a Bang!

While studying about space and the universe in Earth and Space Science, a distant memory surfaced from when I was in the fifth grade. Every year our school did a french language speech competition for students from grades 4-8 and for some strange reason, 10-year old Chloe decided to do her speech about the dominant theory in regards to the origin of our universe; the theory of the Big Bang.

Now I really don't remember what I said exactly in that speech, all I know is that it was apparently pretty good because I ended up having to recite it in front of the school. Where did that confidence come from, and where did it go? No one knows. it's one of the greatest mysteries of the universe. Anyways, all jokes aside I thought about how things might have changed since I did my original research about the topic and also how I might have changed (in that I can probably handle more complicated research nowadays) and decided that I should kind of revive my old passion and see what I might find.       
         

                The basic theory of the Big Bang is that the universe began as a hot dense mass and had a diameter of only a few millimeters. In a trillion-trillionth of a second, this mass expanded to astronomical scope and continued to expand (albeit much more slowly) [source]. At first, the universe was actually expanding at a rate faster than the speed of light, which in fact does not violate laws of physics because laws state that light is the fastest that anything can travel within the universe, and that doesn’t include the universe itself. 

By observing the Doppler shift of many different stars, Hubble discovered that everything was moving away from us [source]. He could determine this fact because the visible light waves emitted by these stars were becoming longer and going through redshift, which, according to the Doppler shift, means that they must be moving away from the observer.

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Some of the most important evidence to back up the theory of the Big Bang was predicted in 1948 by Ralph Alpher, but actually discovered by accident 17 years later by Robert Wilson and Arno Penzias of Bell Telephone Laboratories; cosmic microwave background. Cosmic microwave background (also known as CMB) are radio waves from about 380,000 years after the big bang, when light was first able to shine as a result of electrons grouping up with nuclei and forming neutral atoms. Previously, the electrons had scattered the photons (light) to scatter, therefore the forming of neutral atom allowed light to finally shine [source]. Wilson and Penzias created a radio receiver and were getting very strange results. At first, they thought that their results were because of pigeons and their dung, but an astronomy team led by Robert Dicke that were searching for CMB realized that it must be the cause of Penzias and Wilson's strange readings.

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This video details an important discovery that happened in March of last year; evidence of gravitational waves. Gravitational waves are described as ripples in space-time caused by extremely violent events, such as the Big Bang. After searching for 9 years, researchers in the South Pole have found the first ever evidence for gravitational waves and more importantly, the first concrete evidence for the cosmic inflation theory (the theory that the universe expanded rapidly in the first trillion-trillionth of a second of it's life) [source].

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This discovery could likely be the biggest discovery in astronomy since the realization that the rate of expansion of our universe is actually accelerating, a discovery made in 1998 as a result of observations of very distant supernovae that were made in order to calculate the deceleration. Up until then, it had always been believed that the amount of matter in the universe would eventually slow the expansion because of the gravity the mass creates. The discovery that the rate of expansion was expanding led to the creation of the idea of "dark energy" which is simply the term to explain the amount of outward force that would be needed to overcome the inward force of gravity and continue to accelerate the expansion. Scientists realized that either 75% of the universe is dark energy that exerts this outward force, or Einstein's Theory of Relativity must be wrong. At this point, dark energy is a complete mystery, it has a name, but that is almost all that we know about it [source]. 

To most people, the fact that we literally have no idea what makes up 96% of our universe is terrifying, and I agree that it can be scary to be in the dark about something. Some people may feel lost or insignificant when they think about the scale of the universe, but personally i find it so reassuring and inspiring. Thinking about how much there still is left to discover gives me hope that maybe I can contribute to something really significant, but also thinking about things on the scale of the universe makes me feel so much less stressed about my problems, I mean, why do I matter when our entire solar system doesn't even make a dent when it comes to the scale of the universe. Space is where the most mystery is, but that means it's also where the most discovery can happen. Remember, the sky really is the limit!

Works Consulted
"Dark Energy, Dark Matter." NASA Science. NASA, n.d. Web. 17 Jan. 2015. <http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/>.
Howell, Elizabeth. "What Is the Big Bang Theory?" Space.com. Purch, 19 Mar. 2014. Web. 17 Jan. 2015. <http://www.space.com/25126-big-bang-theory.html>.
"Origins of the Universe." National Geographic. National Geographic Society, n.d. Web. 19 Jan. 2015. <http://science.nationalgeographic.com/science/space/universe/origins-universe-article/>.
"The Big Bang - NASA Science." NASA Science. NASA, n.d. Web. 18 Jan. 2015. <http://science.nasa.gov/astrophysics/focus-areas/what-powered-the-big-bang/>.
Wall, Mike. "Smoking Gun for Universes Incredible Big Bang Expansion Found." Space.com. Purch, 17 Mar. 2014. Web. 17 Jan. 2015. <http://www.space.com/25078-universe-inflation-gravitational-waves-discovery.html>.
"What Is Dark Energy?" HubbleSite. N.p., n.d. Web. 19 Jan. 2015. <http://hubblesite.org/hubble_discoveries/dark_energy/de-what_is_dark_energy.php>.
"Why Is the Universe Speeding Up?" The Dark Energy Survey. The Dark Energy Survey, n.d. Web. 20 Jan. 2015. <http://www.darkenergysurvey.org/>.

Earth's Magnetic Apocalypse?

A few years ago, I saw a documentary that talked extensively about Earth's magnetic poles and the possibility that they might be preparing to flip. I remember it very well because it sounded terrifying and had the possibility of being deadly. To make it worse, this flip was supposedly long overdue!

Now, maybe 6 or 7 years later, I've just rediscovered my childhood fear while reading about the magnetic poles in my textbook. I tried to find the same documentary that scared me all those years ago, but all that I could find was a documentary broadcasted by PBS called Magnetic Storm and an episode of "The Nature of Things" called When North Goes South. I've learned many things from both of these documentaries, but the gist of this whole idea is that scientists have deduced from the direction of magnetism of older rocks that in Earth's history, the poles have flipped roughly every 200,000 to 300,000 years. The ominous part however, is that we are long overdue for a pole reversal; they haven't flipped for 780,000 years [source].

Before a reversal, the magnetic field's strength usually weakens very slowly, but our field seems to be weakening a lot faster than usual: at about 5 percent per decade rather than 5 percent per century [source].

The Earth's magnetic field protects us from solar wind, which is essentially just radiation from the sun. Without the protective magnetic field, cancer rates would increase and genetic mutations are possible, however it's debatable whether the increase in cancer rates will be enough to even be noticeable [source].



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Most likely the worst affect that we'll get from the reversal of the poles is an interruption in our

 electric grid. Okay, so that seems like no big deal, but with our growing dependence on technology, the human race will likely be heavily impacted by the solar storms that can now get close enough to affect satellites. Most of the problems thus far have been in the northern hemisphere, where the field is weakest, but with the wandering pole, the effects could easily spread [source].


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It is highly unlikely that the field would disappear completely (if that happened, we really would be in trouble) because it's formed by the convection currents of molten iron in Earth's core. The iron will cool down eventually, which is exactly what happened to Mars billions of years ago, but not for a very very long time [source]. The convection creates electrical currents which then create the magnetic field that protects us from the dangerous radiation from the sun.

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Both documentaries suggested that during the process of the polar flip, there will likely be not only two, but several different north and south poles around the globe. It would probably mean a lot of confusion with navigation, and maybe some electrical problems, but nothing more serious than that.



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Just as every magnet has a positive pole, every problem has a bright side! During the magnetic flip,   the Aurora Borealis/Australis will be visible all around the world, almost every night. So when your satellite TV isn't working because the satellite has been damaged by some pretty harsh solar storms, you'll have something to look at!


*All gifs made by me from this video

What Will Happen When the Earth's Magnetic Field Switches. (2014, April 17). Retrieved October 20, 2014, from http://gizmodo.com/what-will-happen-when-the-earth-s-magnetic-field-switch-1564164183

Dickerson, K. (2014, July 9). Earth's Magnetic Field Flip Could Happen Sooner Than Expected. Retrieved October 20, 2014, from http://www.scientificamerican.com/article/earth-s-magnetic-field-flip-could-happen-sooner-than-expected/

What Happens When The Poles Flip? (2014, March 20). Retrieved October 20, 2014, from http://www.universetoday.com/110475/what-happens-when-the-poles-flip/

Dunbar, B. (2011, December 5). 2012: Magnetic Pole Reversal Happens All The (Geologic) Time. Retrieved October 20, 2014, from http://www.nasa.gov/topics/earth/features/2012-poleReversal.html

Earth's magnetic field can flip in less than 100 years, new study. (2014, October 25). Retrieved October 20, 2014, from http://thewatchers.adorraeli.com/2014/10/15/earths-magnetic-field-can-flip-in-less-than-100-years-study/

Nova - Magnetic Storm - Earth's Invisible Shield. Retrieved October 20, 2014, from http://www.youtube.com/watch?v=NJUTUFAWfEY

When North Goes South - The Nature of Things. (2013, April 10). Retrieved October 20, 2014, from http://www.cbc.ca/natureofthings/episodes/when-north-goes-south

The Mystery of Black Holes

With so much unknown about the universe that we live in, it's hard to know which theories are true and which are just pure speculation, but black holes seem to be the real deal. I saw a documentary that really got me started on black holes and their origins and it fascinates me how little we really know about them.

Just a few days ago, the existence a black hole 400 times the mass of our sun in the Cigar Universe has been confirmed by researchers from the University of Maryland [source]. Not many black holes have been discovered, especially of intermediate size like this one, so this is an important scientific discovery!

But how is a black hole created?

When the biggest stars die, they explode into supernovas, like the image below.

Once a star expands to a certain extent, it has too much mass to keep from collapsing into it's own gravity. The mass becomes so great that not even light can escape the gravitational pull of the collapsed star. This is what we consider to be a black hole.




The interesting thing about this newly discovered black hole is that we haven't really come across a black hole this size before. Most of the known black holes in the universe are 10-25 times the mass of our sun and are usually only discovered when another star begins orbiting them, making it look like the star is orbiting nothing, or when light from another star is bent while getting sucked into the gravitational pull of the black hole. The other types of known black holes are called "supermassive" black holes [source]. These are billions of times the mass of the sun and are hypothesized to be the centre of every galaxy. Many scientists believe that the existence of galaxies is because of the gravitational pull of these massive black holes pulled the galaxies, as we know them, together.

Seen to the right is an animation representing gravitational lensing, which is essentially when light is bent by the gravitational pull of an object in space, in this case a black hole [source]. In the animation, there is a galaxy behind the black hole and the light is bent and distorted by the extreme gravity and mass of it, creating a distorted sort of double-image.





There is still some doubt regarding the existence of black holes and it has become sort of a controversial subject in the scientific community. Supposedly, at a certain distance away from a black hole, the gravity is so much and space-time is so warped there is no possibility for anything - even light - to escape. This point is known as the 'event horizon' of that black hole. However, the reputable scientist Stephen Hawking has recently suggested that this might not be the case. Hawkings suggests that it is against fundamental laws of physics. Thermodynamics' second law states that the amount of disorder [entropy] in a system can never be destroyed, which basically boils down to the fact that information can never be destroyed [source]. The common theory about black holes had been that once something crosses the event horizon, it won't ever come out again, and Hawkings suggests a reformulated hypothesis. He is proposing the existence of an 'apparent horizon' which would only contain the matter temporarily before releasing them, although it would be in a more distorted form [source] .

Hawkings does admit that his new theory far from explains the true mystery of black holes, as it doesn't align perfectly with all laws of physics, but it's a step in the right direction, and hopefully we'll be making more leaps and bounds in the near future.

The first theory about the possibility of black holes was over two hundred years ago, and since then we've learned so much, but we're still so clueless about this mysterious universe that we live in. Will we ever figure it all out?