Learning Device (MacBook)
1) Take pictures of Jupiter and its 4 moons every night at 9pm over 2 weeks through a telescope.
2) Merge all the pictures taken over the 2 weeks together into 1 picture using editing software.
3) Plot a graph of the positions of each of the 4 moons against Jupiter over 2 weeks.
4) Determine the period and semi-major axis of each of the 4 moons.
5) Measure the distance between the moons and the center of Jupiter from the groups.
6)Use the formula : M=4pi^2a^3/GP^2
- (a) represents the semi-major axis (radius) of the orbit of the moon
- (p) is the period of the moon.
- (g) = 6.67 x 10-11 m3/kg-sec2
- (M) is the mass of Jupiter.
- (M) is the mass of Jupiter.
Figure 1: Telescope used to take pictures of Jupiter
We set up the telescope first (8pm). Then when it is night we point the telescope to roughly where Jupiter’s location is. Then we try to locate Jupiter and when we do we use different magnifications to see which one is better. After that when we found the perfect spot then we attach the camera to the telescope’s camera mount and take a picture of it. Then we transfer the data to our learning device to start our calculation. We observe the amount of pixels different from Jupiter and its moons. Then we would calculate how much one pixel is in real life kilometers. Then we can find the distance in real life and get the data we need to calculate the mass of Jupiter.
2.4 Risk Assessment and Management
During the experiment there are certain risks which might happen. For us one of them is the risk that the telescope might drop on our foot while observing. It may happen as sometimes we may not notice that one screw or adjuster could be loose and can drop on our foot. The assessment of this is medium as it can be easily solved by just being careful where we put our foot during observation and make sure the telescope is tightened properly before observing.
Our experiment is conducted in the dark, which increases the risks of tripping over things on the ground. The assessment of this risk is low as we usually put things on the table, not on the floor. We can avoid this by turning on background lights so that it can illuminate the ground for any unwanted obstacles.
For our experiment we need the surrounding to be dark that way observing Jupiter would be easier. However that benefit could also be a risk as if it is very dark it is very hard to see. When it is hard to see we may accidentally trip over something and hurt ourselves. The assessment for this is low as we can just be careful of where we are walking.
The last risk we have is that we might fall off the balcony. We are observing on a balcony as it is open to the outside and easier to observe. However the balcony is very high and we might accidentally fall off. Especially if some people play prank while observing. It might accidentally make the victim fall off the balcony. The assessment for this is high as this will most probably result in death which no one wants. We can avoid this by staying a safe distance from the balcony edge.
2.5 Data Analysis
After we took the photograph, we uploaded them onto a computer and measured the diameter of Jupiter in pixels. We also measured the distance of all the moons from the centre of Jupiter in pixels.
We assume that Jupiter’s diameter is known and measures 139,822 km. From that information we can deduce the distance of one pixel on the picture by dividing 139,822 by Jupiter’s diameter from each of the photos. The results would be in km. After we know the distance of 1 pixel, we are able to deduce the distance of the 4 moons from Jupiter for every image.