Image

What are Dark Matter and Black Holes?

by Briana Purves, 6th period CP Physics

Most people consider dark matter and black holes to be mysteries; however, with the help of scientists and technology, these mysteries can be understood! Dark matter is a nonluminous material that exists in space and can appear in many different forms. Black holes are a region of space with a gravitational field so intense that no matter or radiation can escape it. Black holes also have the ability to deflect light, but dark matter does not. Overall, there are many things that we can learn about both dark matter and black holes.

Nonluminous, dark matter is postulated to exist in space and can take any of several forms, including weakly interacting particles or even high energy randomly moving particles created soon after the Big Bang. Although it is not in the form of visible stars and planets, scientists have deduced the existence of dark matter because there is not enough visible matter in the universe to account for the gravitational effects present in the universe. Research supports that dark matter makes up a substantial percentage of the matter-energy composition of the universe, while the rest is dark energy and “ordinary” visible matter. Dark matter is not in the form of dark clouds filled with normal matter, but can be seen as matter made by baryons particles that are composed of protons, neutrons, and electrons.

Dark matter was originally known as the “missing mass” until Fritz Zwicky discovered that the mass of all the stars in the Coma Cluster of galaxies provided about one percent of the mass required to keep the galaxies from escaping the cluster’s gravitational pull. Missing mass remained a question until the 1970s when two American astronomers proved its existence through the idea that the mass of the galaxy within the orbit of stars must increase linearly with the distance of stars from the galaxy’s center. Also, dark matter is not capable of being composed of antimatter, because scientists would be able to see gamma rays that have been produced when antimatter annihilates with matter. Scientists are still unsure of the exact composition of dark matter, but the most common view is that dark matter is made up of exotic particles called axions, or weakly interacting massive particles.

Conversely, black holes are a region of space that has a gravitational field so intense that no matter or radiation can escape it. The gravity of a black hole is so strong because the matter has been squeezed into the tiny space, not allowing it to escape. People cannot see black holes, as they are invisible to the human eye, and can only be detected by advanced special telescopes. Black holes come in many different sizes and shapes, from the size of a large planet to as small as just one atom. Even the extremely small black holes contain massive amounts of matter inside.

One type of black hole that has been discovered is called a Stellar. Stellars can grow to be up to twenty times as big as the mass of the sun; however, there are black holes that can grow to be even bigger; these black holes are called Supermassives. Supermasssives can have masses up to one million times greater than the sun’s mass. Scientists have found that these Supermassive black holes are most commonly found in the Milky Way (also known as Sagittarius A) and have a mass equal to four-million suns and a few million earths.

Black holes are formed when the center of a star falls in on itself causing a supernova or when an exploding star blasts parts into space. Many black holes cannot be seen today because of the strong gravitational pull of light into the center of the hole. When a black hole and a star are near each other, high energy light is made that can only be seen by satellites and telescopes in space.

Einstein’s Law of General Relativity explains why black holes deflect light. Einstein’s law states that a ray of light arriving from one side of an object is bent inwards so that its apparent direction of origin, when viewed from the opposite side, is seen as a different angle. The observed gravitational effect between masses will result from their warping of space-time. Einstein’s Law of General Relativity predicts that every object’s gravitational field bends light rays which is called gravitational lensing. According to Wikipedia, “A gravitational lens is a distribution of matter between a distant source and an observer, that is capable of bending the light from the source, as it travels towards the observer.” Einstein’s Law of General Relativity also supports that the gravitational fields of massive objects causes a distortion in space-time. Einstein’s Law of General Relativity proves just how black holes have the capability to deflect light, as they are able to bend light rays through its gravity.

People have the capability of learning infinite things about both dark matter and black holes. Such things can include how dark matter is known as a nonluminous material that is postulated to exist in space and that can take any of several forms, while, contrarily, black holes are known as a region of space that has a gravitational field so intense that no matter or radiation can escape. Black holes also have the capability to deflect light, which can be proven by Einstein’s Law of General Relativity and through gravitational lensing. If all of these things can be learned about dark matter and black holes through the writing of this one essay, imagine what can be learned throughout a lifetime.

About the author: IMG_1303 (2)
Briana Purves is not only an excellent physics student, she is an outstanding softball player.

Quantized Magazine. All Rights Reserved.

Advertisements