Running Head: SCIENTIFIC OBSERVATION PROJECT REPORT 1
SCIENTIFIC OBSERVATION PROJECT REPORT 6
SCIENTIFIC OBSERVATION PROJECT REPORT
Name
Professor
Institution
Course
Date
Scientific Observation Project Report
A Description
If we could estimate all the stars we observe in the sky, it’s difficult to assess physically. Some students may think we can observe millions of stars with the unaided eye. However, under ideal conditions, one can observe almost 3,000 stars with the unaided eye. For that case, this article aims to articulate and closely demonstrate the total number of stars visible to the eye as estimated from various samples, and to investigate how the number changes when the moon is visible.
Details about the Equipment
The project involved several equipment. Using geometry and readily available material, it was possible to approximate the total number of stars in the entire sky visible to the unaided eye at any given time. Though it seems difficult, but this article simplifies it out and the examination provided shows how easy it is to count the stars while doing it in a logical manner. The equipment needed were one paper towel tube of about 30cm long, a calculator, a pencil, writing paper, and one clear, dark night and one clear night with bright moonlight.
When and How Observations were taken and of what object
Observations were taken during a two nights, one dark night and one clear night, using the following procedure:
1. Finding the darkest spot in the house, and trying to block much as much light from the streetlights as possible.
2. Taking the paper towel tube and holding it up to one eye, then counting the stars without moving the tubes while counting.
3. Noting down the number of stars seen on the sheet in the first box.
4. Spotting another part of the sky with the tube and recording the number of stars seen on the next box.
5. Repeating the same process from eight more parts of the sky and recording the data on the sheet.
6. Averaging the count of all these 10 trials.
The Variables and Control
Through averaging out all types of stars in the sky, this would result to more than 100 billion of stars in the galaxy. Nevertheless, depending on the number and sizes of stars than our own sun, this is subject to change. Other estimates asserts that the Milky Way would have more than 200 billion of stars.
Calculations
In order to get the possible number of stars that are visible with a paper towel tube, we use a statistical method of sampling, where number of stars are chosen randomly from distinct fractions of the sky. The numbers are then scaled up to get the entire estimate across the sky. This is an achievable if we consider the length of an observer’s tube to be R so that open-end area of the tube would be ? (D/2)2.
Data and results
Observation
Altitude
Azimuth
Number of Stars
Time (p.m)
Nights
1
10?
255? SW
93
8:20
Dark
2
7?
215? SW
56
8:32
Dark
3
30?
212? SE
287
8:42
Clear
4
40?
265? NE
304
8:49
Clear
5
19?
150? SE
69
9:06
Dark
6
60?
217? SW
496
9:10
Clear
7
70?
282? NW
578
9:13
Clear
8
50?
173? SE
414
9:17
Dark
9
69?
116? SE
512
9:23
Clear
10
20?
126? SE
114
9:30
Dark
TOTAL
2923
Calculate the average number of stars visible in your tube:
Average number of stars = __total number of stars _
Number of observations
Average number of stars = __2923_ = 292.3
10
Similarly, take the length of the paper towel tube as the radius of a sphere. So, if the end of the tube swept a full surface of a sphere, then without doubt, the surface area would be expressed mathematically as A=(4?L2)/2, where L is the length of the tube, or correspondingly, the radius of the sphere. Take the length of the paper towel tube to be 30cm, and so, the sphere of that radius has got a surface area of about 5655cm2. This indicates that as one looks via the tube, he/she sees an area equivalent to that of a circle with the same radius. But, (Area of hemisphere of sky)/ (Area of end of tube) = (4?L2)/2/?(D/2)2 = 8 L2/D2, indicating, while looking at the sky with such a tube, one sees a portion of a sky equally proportional to the area of tube-end divided by the tube-length spherical area, simply, 32 – total area of the sky. This implies that it would take almost 32 paper towel tubes to observe the whole sky, and half of it would cover from one side of horizon to the other. Because we only see half of the sky, then 32/2 = 16 would be used as the multiplication factor. Therefore, the total number of stars in the paper towel tube in the entire sky would be, 32*292.3 = 9,354 stars in a projected spot.
Conclusion
To sum up, keeping in mind that the above calculations lead to an estimated total number of stars visible to the unaided eye all over the Earth, we can thus estimate the stars visible to the unaided eye from any location by dividing the total by half since only half of the sky is visible any of the location at any time. Under ideal conditions from the whole planet, the number of stars change when the moon is visible, and almost 9,354 stars are visible to the unaided eye. But in areas that are heavily developed, the number can significantly drop to a few thousands; in a middle of a city, it can drop to only a few hundreds. The exercise can be more accurate if and only if; climate trends from a background are naturally variable, and are geographically homogenous over long time scales. As if that is not enough, statistics on temperature and humidity should also be noted as this limits the maximum focus with naked eye. If not so, just consider the Milky Way. While looking at the Zenith and toward the horizon, the quality of the sky diminishes and one observes twinkling stars. Thus, there is need for integrated approach while observing, and accurate systems to robust the invariant allusions. If the length and diameter of the tube is changed, it would affect the results of the stars visible. If the length and diameter is reduced, the number of stars would reduce because the total number of stars visible with the paper towel tube varies with length of the tube. The same case applies when the length and diameter is increased, where the number of stars would significantly increase, since an observer will have wider cross section of the tube that will focus widely on the sky.
