Discovering the Universe - Paper Example

Question One

Dark matter refers to unidentified elements in the skies that do not take the form of stars, clouds, or other planets. They are invisible to the various inventive ways used to observe the stars, such as electromagnetic radiation. Unlike other bodies, particles that make up dark matter are not visible as they do not absorb, reflect, or emit light. In astronomy, the study of dark energy is essential as it helps one to obtain crucial information about the Universe (Comins & Kaufmann, 2011). The knowledge on the dark matter will also help astronomers to answer questions on particular topics, such as the size and shape of the earth. Moreover, it will enable astronomers to solve contentious issues relating to the formation of galaxies and the expansion of the Universe.

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

Order now

21 cm Radiation

21 cm radiation refers to a wavelength line of hydrogen gas. The line is formed 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 in the atoms. The 21 cm wavelength line has been crucial to the mapping of hydrogen across the galaxy. Mapping is conducted to determine certain aspects, such as the levels and velocity of hydrogen in the sky (Comins & Kaufmann, 2011). In astronomy, the 21 cm radiation line is central to measuring hydrogen levels beyond limitations of factors such as dust clouds. Thus, the knowledge on 21 cm radiation will help people to understand the Universe clearly.

Question Two

The Milky Way Galaxy is the center of the Universe. It takes the form of 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. The galaxy has a dense center that one cannot see through to the other side. Its galactic center has a massive black hole, commonly known as Sagittarius (Comins & Kaufmann, 2011). The Milky Way galaxy has a bar across its center region. It forms part of the larger set 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, thus increasing in size. It contains two significant arms: the minor arms and the 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. The galaxy's red dwarfs are the most outstanding features among the billions of stars in the sky.

Question Three

Einstein's theory establishes the link between space and time. His specialist theory argues that when an object consistently moves in a straight line at a fast pace, its mass becomes infinite. Einstein further asserts that an object cannot travel any faster after attaining the light speed. 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 some vital 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 on the ground irrespective of the surroundings. He presented equations that elaborated the concept of warping and creation of gravity (Reyes et al., 2010). The theory thus enables scientists to predict the impact of mass on space and time. One can tell easily determine how gravity affects matter, space, time, and light. The theory concluded that a larger mass creates a more significant warp.

Question Four

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 speed. 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, which channel particles out of the oscillating neuron stars along two magnetic poles. As the particles 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 rotates along the star. Apart from variations in brightness, radio astronomers have also identified differences in successive pulses released by the 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.