Space Essay Example for Free Use

Question One - Dark Matter and 21 cm Radiation

(a) Dark Matter

Dark matter refers to unidentified issues in the skies that do not take the form of stars, clouds or other planets. They invisible to the various inventive ways used to observe the stars such as electromagnetic radiation. Particles that make up dark matter are not visible since, unlike other bodies, they neither absorb, reflect nor emit light. In astronomy, dark energy is essential to gaining insight on critical issues about the universe (Comins & Kaufmann, 2011). The knowledge will help astronomers answer questions about unique features such as the size and shape of the earth. Through studying dark matter, contentious issues regarding the formation of galaxies and the universe's expansion model can be solved.

Is your time best spent reading someone else’s essay? Get a 100% original essay FROM A CERTIFIED WRITER!

Order now

(b) 21 cm Radiation

21 cm radiation refers to a wavelength line of hydrogen gas. The line forms as a result of emission of radiation from hydrogen that has a frequency of 1420 megahertz. The discharge of the gas occurs due to energy changes that occur in the atoms. The 21 cm wavelength line has been crucial to the mapping of hydrogen across the galaxy. Mapping is conducted to determine aspects such as levels of hydrogen in the sky and its velocity (Comins & Kaufmann, 2011).In astronomy, the 21 cm radiation line is central to measuring hydrogen levels beyond limitations of factors such as dust clouds. The insight will contribute to the human knowledge of the universe.

Question Two - The Milky Way galaxy

The Milky Way Galaxy is the center of our universe. It takes a barred, spiral, galaxy shape that has four main arms in its disk. It comprises billions of stars including the sun and all the planets that revolve around it. With several light years apart, the galaxy has a dense center that one cannot see through to the other side. Its galactic center has a massive black hole, Sagittarius (Comins& Kaufmann, 2011). The Milky Way galaxy has a bar across its center region. Formed billions of years ago, the Milky Way forms part of a larger group of galaxies known as the Group.

The Milky Way galaxy first appeared as a region of dense concentration of stars. Over time, it acquired more particles, growing larger. It contains two significant arms, minor arms, and spurs. The Orion Arm comprises the sun and the solar system. It lies between Perseus and Sagittarius. The galaxy is in constant rotation, moving the arms through space. The galaxy's velocity in space is at an estimated 550 kilometers per second (Comins & Kaufmann, 2011). Members of the solar system, such as planet Earth, do not orbit within the plane of the galaxy. Instead, they rotate at a tipped angle. Among the billions of stars in the skies, the galaxy's red dwarfs are its most outstanding stars.

Question Three - Einstein's theory

Einstein's theory establishes the link between space and time as an object travels at very high speeds by combining it with the law of gravity. His specialist theory argues that when an object consistently moves in a straight line at a fast pace, its mass becomes infinite. Einstein offers that when an object attains the speed of light, it cannot travel any faster. Thus, he included acceleration into the theory and derived the general relativity theory (Reyes et al., 2010). Einstein recognized gravity as a force that disturbs the space and time balance. Therefore, his approach contained ideas such as warping and gravitational lensing.

The theory attributed gravity to actions such as bending or stretching of the space and time balance. The basis of Einstein's argument was that there is a uniform rate of acceleration for objects falling to the ground no matter the environmental context. He presented equations that elaborated the concept of warping and creation of gravity (Reyes et al., 2010). Through the theory, it became possible to predict the impact that mass would have on space and time. Thus, one can tell how gravity affects matter, space, time and light. The theory concluded that the larger the mass, the more significant warp it would create.

Question Four - Pulsars

Pulsar, also known as pulsating radio sources, refers to objects that could oscillate, orbit, or rotate on a regular period characterized by periodic radio emissions. Unlike other regular stars, pulsars were highly magnetized and could move at fast speeds. By use of radio pulses, astronomers can detect and monitor their movements (Lorimer, 2008). Most of the pulses astronomers record is on the electromagnetic spectrums. Other regular sources of extraterrestrial radiation releases are on optical wavelengths and X-ray wavelengths.

Pulsars emit electromagnetic radiation from a neutron star's rotational energy. They also have strong magnetic fields. The fields channel particles out of the oscillating neuron stars along two magnetic poles. As the particles leave jet out, they display strong, light beams. In most cases, when the process occurs, the magnetic field and the spin axis are misaligned (Lorimer, 2008). As a result, pulsars release radiation through particles and light beams of varied intensity that get carried around in the skies as the star rotates. Apart from variations in brightness, radio astronomers have also identified differences in successive pulses released by pulsars.

References

Comins, N. F., & Kaufmann, W. J. (2011). Discovering the universe. New York: W. H. Freeman & Co.

Lorimer, D. R. (2008). Binary and millisecond pulsars. Living Reviews in Relativity, 11(1), 8.

Reyes, R., Mandelbaum, R., Seljak, U., Baldauf, T., Gunn, J. E., Lombriser, L., & Smith, R. E. (2010). Confirmation of general relativity on large scales from weak lensing and galaxy velocities. Nature, 464(7286), 256.