Procedures in the Physical Sciences, Research Paper Example

Challenges in Measurements and a Survey of Safety

Part One

In the field of astronomy, three specific methods are generally utilized to directly measure the distance of objects in the universe–the astronomical unit (AU); the light year; and the parsec. However, these three direct methods of distance measurement are not wholly accurate, due to the fact that some cosmic objects like galaxies are so far away that direct measurement methods only yield a basic distance. Therefore, astronomers utilize three indirect measurement methods which tend to be more accurate–parallax, and the red shift/Hubble Constant.

The first method or the astronomical unit can be defined as the “average distance between the Earth and the Sun” or approximately 93 million miles or 150 million kilometers. Generally speaking, this form of measurement is only used to calculate distances within our own solar system, such as the distance between the Earth and the planet Jupiter or Saturn. As an example, the planet Mercury is “about 1/3 of an A.U. from the Sun” or approximately 30 million miles, while the farthest planet Pluto is “about 40 A.U. from the Sun” or approximately 3.7 billion miles (Distance Measure, 2013).

The second method or the light year is utilized when an object in space is just too distant to measure via a “relatively small unit of distance such as an astronomical unit” and is mostly applied to objects that lie outside our own solar system. By definition, a light year is the “distance that light can travel in one year in a vacuum” or empty space and equals to about 186,000 miles per second. Thus, light travels a distance of about 5,880,000,000,000 miles in one year which figures to about 63,240 astronomical units. A good example is the Andromeda galaxy, the closest galaxy to our own Milky Way which lies at a distance of approximately 2.3 million light-years (Distance Measure, 2013).

The third method or parsec equals to about 3.26 light years and is measured via the “length of the long leg of a right triangle whose short leg is one astronomical unit when the angle between the Sun and the Earth” is one arcsecond. This term stands for “parallax of one arc second” or one kiloparsec (kpc), being one thousand parsecs. This method is generally utilized to measure the approximate distance to an object that lies far beyond our own Milky Way galaxy (Distance Measure, 2013).

To compensate for the approximate measurements made via the astronomical unit, the light year, and the parsec, astronomers depend on three indirect methods of measurement–parallax or stellar parallax, being “a nearby star’s apparent movement against the background of more distant stars as the Earth revolves around the Sun,” and the red shift/Hubble Constant which states that “the distance to a given galaxy or other celestial object is proportional to the recessional velocity as measured by the Doppler red shift” (Distance Measurement in Astronomy, 2013), meaning that the more distant an object is the more its light shifts toward the red end of the spectrum.

Concerning two of the most historically influential tools or techniques utilized in the modern physical sciences, the first is known as a mass spectrometer which is utilized to “measure the characteristics of individual molecules” by converting them to “ions so that they can be moved about and manipulated by external electric and magnetic fields.” The basic workings of this device are 1), a small sample is ionized, usually to cations by loss of an electron; 2), the ions are sorted and separated according to their mass and charge; and 3), the separated ions are then measured with the results displayed on a chart (Reusch, 2013). This device has helped scientists to understand the structure of molecules and atoms and in astronomy aids in measuring the wavelengths and intensities of celestial objects like stars and galaxies. The second tool or device is known as a seismometer or seismograph which is utilized by geologists to detect and record earthquakes. This device works via a “mass attached to a fixed base and during an earthquake, the base moves but the mass does not. The motion of the base with respect to the mass is commonly transformed into an electrical voltage” which is then recorded on paper, magnetic tape, or another recording medium (Earthquake Hazards Program, 2012). As an important tool for geologists, the seismograph aids in understanding the strength of an earthquake (i.e., the Richter scale) and where the epicenter or place of origin is located within the physical Earth.

Part Two

One of the greatest hazards associated with research in the physical sciences is radiation exposure or working with materials that are radioactive, such as ore samples or elements that have been altered as radioactive isotopes. According to the U.S. Environmental Protection Agency (EPA), “radioactive materials that decay spontaneously produce ionizing radiation which has sufficient energy to strip away electrons from atoms,” thus creating two charged ions, or to “break some chemical bonds” (Radiation Protection, 2012). Therefore, in order to protect the human body from exposure to radiation, researchers wear protective outer clothing that shields them from the harmful effects of radiation, especially “ionizing radiation from alpha and beta particles, gamma and X-rays” (Radiation Protection, 2012).

As to the safety of the global community related to advancements in the physical sciences, when scientific research results in new discoveries that pose a health hazard to the general population, such as discoveries concerning new ways to generate power (i.e., fusion power as contrasted with fission power), all health hazards or potential negative consequences must be made known to the public and governmental officials. In some instances, new governmental regulations, such as those now imposed by the EPA, must be created in order to guarantee that the safety and well-being of the public is not compromised.

References

Distance measure. (2013). NASA. Retrieved from http://coolcosmos.ipac.caltech.edu/cosmic_classroom/cosmic_reference/distance.html

Distance measurement in astronomy. (2013). Retrieved from http://hyperphysics.phy-astr.gsu.edu/hbase/astro/distance.html

Earthquake hazards program. (2012). U.S. Geological Survey. Retrieved from http://earthquake.usgs.gov/learn/glossary/?termID=167

Radiation protection. (2012). EPA. Retrieved from http://www.epa.gov/radiation/understand/health_effects.html

Reusch, W. (2013). Mass spectrometry. Retrieved from https://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/Spectrpy/MassSpec/masspec1.htm