Category

Sakuragaoka Junior High School (2003)

Observation

Observation

Observations have done in any spots depending on each student's idea. A coloured sticker was pasted on each observation spot.

Prior Expectations

Point A, Point B and Point C were picked up in the observation area. Which points will be best for observing stars?

	Point A（New residential district）Bright; Many new outdoor lights Second position!?
	Point B（Old residential district）Most outdoor lights are old and shine only down below. Best position!?
	Point C（High-street）Over against a main street; Outdoor lights shine only the street. Worst position!?

Collecting the prior expectations, it is B>A>C in order of preference.

Results

The light pollution map in Sakuragaoka section was constructed using the results. Contrary to the expectations, the worst observing point is Point A !

The graph was made to compare the views from north, south, east and west. This graph shows fewer faint stars of the third or fourth magnitude were found in the eastern and southern sky. That means the night sky environment of the eastern and southern sky is not as good as the west or north. The results agree with the results from "The light pollution map in Sendai" researched by Sendai Observatory with students in primary or secondary school in Sendai.

Discussion:　What influences night sky environment?

According to the results above, the influencing factors are listed below;
１．The types of outdoor lights are different depending on time of development of residential sites, which influence night sky environment.Both point A and point B are in same district, but point A is newer with lighter outdoor lights.
２．Even in same place the night sky environment is not same between shop open time and closed time. Night sky environment depends on time of day.

Shop open	Shop closed

３．There are varying results even from a single observing site because some points have places with bright outdoor lights and without close together. For example, Main gate of Sakuragaoka Junior High (left photo) is dark without any lights because the school is closed, whereas the street side against the main gate (middle photo) is bright with outdoor lights. Kawadaira 5 cross-point (right photo) is bright only in the cross-point, but dark around there. Thus there are such places, so there are multiple results at a single observing site.

Main gate of Sakuragaoka Junior High	The street side against the main gate	Kawadaira 5 cross-point

Comments

Comments

Q：Comment about the night sky environmental research or the results of it.

• I was surprised to see the worst star observing point was Sakuragaoka7.
• I was surprised to see my expectations did not agree the results.
• I was amazed watching so many stars in Sakuragaoka. I was happy to see many stars.
• I thought there were stars in night sky as I can see, but now I know we can see more if the environment becomes better.
• I see many places in Sakuragaoka are not good to watch stars. I hope Sakuragaoka is going to be better town to watch many stars.
• By this research, I knew we can see stars in various places in our home town, even though it has bright places like the shopping centre.
• I felt Sakuragaoka is not as bright as Akiu.
• It's a pity that the town lights influence other places.

Evaluation

According to the students' look in the class and the comments, the evaluation includes below;

1. The students seem to be bad at reading maps. It took much time to see observing points on the night sky light pollution map. Confirmation of the locations of their home or school are needed before getting data of the night sky environment from the map. This has been done since second term of the class which has three terms.
2. The questions on the worksheet were too obscure to answer. Questions need more examination and should be clearer.
3. Fewer students were aware of the night sky environment of their home town. There were some facts they didn't know before the research.
4. It took much time, but they could have their own idea about the night sky environment in Sakuragaoka section by making the light pollution map.
5. They were able to have chance to see many stars in Sakuragaoka through the research.