Elementary Science
Unit 8:
Developing observational skills: exploring
the relationships between the Earth, the
Sun and the Moon
Teacher Education
through School-based
Support in India
www.TESS-India.edu.in
http://creativecommons.org/licenses/
The TESS-India project (Teacher Education through School-based Support) aims to improve
the classroom practices of elementary and secondary teachers in India through studentcentred and activity-based approaches. This has been realised through 105 teacher
development units (TDUs) available online and downloaded in printed form.
Teachers are encouraged to read the whole TDU and try out the activities in their classroom
in order to maximise their learning and enhance their practice. The TDUs are written in a
supportive manner, with a narrative that helps to establish the context and principles that
underpin the activities. The activities are written for the teacher rather than the student,
acting as a companion to textbooks.
TESS-India TDUs were co-written by Indian authors and UK subject leads to address Indian
curriculum and pedagogic targets and contexts. Originally written in English, the TDUs have
then been localised to ensure that they have relevance and resonance in each participating
Indian state’s context.
TESS-India is led by The Open University and funded by UKAID from the Department for
International Development.
Version 1.0
Except for third party materials and otherwise stated, this content is made available under a
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Contents
Introduction
1
Learning Outcomes
2
1
Misconceptions about the Earth, the Sun and the Moon
3
2
Observing shadows
6
3
Observing the Moon
10
4
Teaching the phases of the Moon
12
5
Games and quizzes
15
6
Summary
17
7
Resources
18
Resource 1: The formation of shadows
Resource 2: Phases of the Moon
Resource 3: The Hindu calendar and festivals
18
18
20
Related units
23
8
References
24
Acknowledgements
26
Transcript
27
Introduction
Introduction
‘Observing’ is something that children and adults do instinctively as they
make sense of the world around them. It is more than simply watching; it is
about recognising that an event or phenomenon is of particular scientific
significance. Observation is therefore an integral part of science education.
Because it is involved in analysing, interpreting and concluding, it is a
fundamental part of the scientific method.
In the elementary science curriculum, observation should take the form of
meaningful practical activities that encourage students to pay close attention
to certain aspects of their surroundings.
This unit will explore misconceptions that students may have about the
Earth, the Sun and the Moon, and their movements. It proposes a range of
practical activities aimed at developing students’ observational skills, thereby
supporting their understanding.
Safety warning!
Students must be advised never to look directly at the Sun, or
through a mirror, as sunlight can damage their eyes even if they
are wearing sunglasses.
Students need to know the dangers of hazards they might encounter
outside the classroom, and should never investigate electrical
equipment, telephones or communications equipment, or work in areas
where machinery or vehicles are likely to operate.
There may also be factors to consider regarding changeable weather
conditions and places of shelter.
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TDU 8
Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
Learning outcomes
After studying this unit, you should be able to:
2
.
recognise the misconceptions that elementary science students might have
about the Earth, the Sun and the Moon
.
plan and deliver practical activities that develop students’ observational
skills both inside and outside the classroom.
1 Misconceptions about the Earth, the Sun and the Moon
1 Misconceptions about the Earth,
the Sun and the Moon
Pause for thought
Think back to your childhood and try to recall what your understanding
was of the Earth, the Sun and the Moon, and the relationships between
them. What misconceptions did you have at the time?
Young students in particular tend to find it difficult to understand that the
Sun is stationary and the Earth is moving around it, as all the observable
evidence suggests that it is the Sun that moves. They may have noticed that
the Sun changes its position in the sky from sunrise to sunset, and might
therefore assume that it is the Sun that moves around the Earth.
Simple activities like the ones suggested below can support your students’
understanding of the relationships between the Earth, the Sun and the Moon.
Pause for thought
.
How have you explained the relationships between the Earth, the
Sun and the Moon to your students? Have you found it difficult to
explain the apparent movement of the Sun?
.
What tools, models or resources have you used to help explain the
Earth’s orbit of the Sun?
‘Being’ the Earth, the Sun and the Moon
This is a straightforward classroom drama activity that can help your
students understand the relationships between the Earth, the Sun and the
Moon.
1 Ask one of your students to ‘be’ the Sun and another to ‘be’ the Earth.
Ask the ‘Sun’ to stand still while the ‘Earth’ moves slowly around it in a
circle.
2 Explain that the Earth orbits the Sun and that it spins on its axis as it
does this. Ask the ‘Earth’ to demonstrate this slow spinning action as it
circles the ‘Sun’.
3 Ask another student to ‘be’ the Moon. Explain how the Moon orbits the
Earth and ask the ‘Moon’ to demonstrate this.
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
4 Finally, ask all three students to combine all their movements. Remind
them that it is only the Earth and the Moon that move; the Sun remains
stationary.
Heavenly Movements
In a large space, such as an assembly hall or outdoor area, organise your
students into groups of three. Ask the members of each group to take the
role of the Earth, the Sun and the Moon, as described above. This activity
could be enhanced by making it into a slow dance accompanied by music.
As the students perform their movements, you can provide them with some
related scientific facts:
.
It takes a complete day – 24 hours – for the Earth to make one full
rotation.
.
It takes 365 and a quarter days for the Earth to orbit the Sun.
.
It takes 28 days for the Moon to orbit the Earth.
.
A full Moon appears every 30 days.
.
The Moon was formed about 4.5 billion years ago, about 40 million
years after the creation of the Earth.
After the activity, you should spend time reinforcing your students’
understanding of these abstract concepts, clarifying these facts, using models
or diagrams if helpful.
Your students can then create their own models of the Earth, the Sun and the
Moon, based on information that you provide on their relative sizes and the
distances between them.
The next activity encourages your students to observe changes in the
position of the Sun throughout the day. When talking about the Sun
changing position, it is important to make it clear (at this stage) that it only
appears to move but does not actually do so. (Please also remember the
safety warning in this unit’s introduction.)
Following the Sun
This activity is best started early in the morning. A compass might be useful
as you will need to establish the directions of east and west.
4
.
On the board, sketch a scene of somewhere on the school grounds. The
scene you choose to sketch should be from a south-facing vantage point.
You may prefer to display an image that you prepared earlier.
.
Ask the students, ‘Does the Sun stay in the same part of the sky every
day?’ and discuss this with them.
.
Take the students outside to the area depicted in the drawing and ask
them to observe where the Sun is in the sky.
1 Misconceptions about the Earth, the Sun and the Moon
.
Invite the students to plot the position of the Sun on the drawing
throughout the school day. Begin by getting one student to draw the Sun
in the observed position, recording the time next to it.
.
Repeat the activity every hour throughout the day.
.
At the end of the day, ask the students to describe what has been
observed – the Sun’s apparent movement over several hours.
.
Repeat the activity the following day, as a means of checking whether
the same pattern occurs.
It may be useful to indicate the points of the compass – north, south, east
and west – on your drawing so that your students can begin to observe and
record the rising of the Sun in the east and the setting of the Sun in the
west.
The way the Sun appears to move across the sky can also be recorded by
painting where the Sun is on a south-facing classroom window at the start of
the school day and every hour subsequently.
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
2 Observing shadows
This section aims to provide some ideas for investigating shadows, and
noting the way their shape, size and position alter over the course of the day
as the Sun changes its location in the sky. In addition to observing, students
will practise key scientific skills such as describing, measuring, recording
and interpreting.
Pause for thought
.
How do you think exploring shadows will support your students’
understanding of the Earth and the Sun?
.
What will your students learn from examining shadows? Note down
as many ideas as you can think of.
Before moving on to investigative work, younger students need to
understand that shadows are created as a result of an object blocking out a
light source, such as a lamp or the Sun. The following activities can be used
with students of all ages to introduce them to the characteristics of shadows
in an engaging way.
Fun with Shadows
1 Create a dark area in a corner of the classroom and allow your students
to explore the different shadows that they can make with a torch and
their hands or other objects.
2 Using an outdoor area on a bright sunny day, ask your students to create
funny shapes using their hands, or leaves, or any other objects they might
find on the ground. Then get them to chase their shadows and play
shadow-boxing.
3 Ask your students to work in pairs and draw around each other’s shadow
using a piece of chalk. At the end, get them to draw around each other’s
feet so that they can mark the spot with their initials. Invite them to
return to the same spot at regular intervals during the day to draw a new
shadow.
The next activity asks you to watch a video of students exploring shadows
and to make notes about what they have learnt.
Activity 1: Investigating changes in shadows
throughout the day
Now watch the video below about students investigating changes in
shadows throughout the day. If you are unable to watch the video, it
shows the teacher introducing the activity to her students inside the
6
2 Observing shadows
classroom, but using the space outside the school to conduct the
investigation. You may also find it useful to read the video’s transcript.
Now watch the video clip. If it is unavailable or has not been
provided separately, you can find it at the TESS-India YouTube
channel. You will find the transcript at the end of this unit.
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
Watch the video clip several times. When you are familiar with the
video, answer the following questions:
.
How do the students record the changing shadows?
.
What data do the students record?
.
Are the students surprised by what they see?
.
What phenomena do they notice?
.
Can the students explain why the shadows changed?
.
What do you think the students learnt from this experience?
Discussion
The students in the video were able to explain how the rotation of the
Earth created the change in the shadows. The activity gave them the
opportunity to see this natural phenomenon happening and to record
evidence that these changes actually took place. As the students carried
out the activity, they had the chance to use key scientific skills such as
observing, measuring, recording and interpreting in a meaningful
context.
The next activity asks you to plan and carry out a student activity that
investigates how shadows change throughout the day.
Activity 2: Exploring shadows by making a sundial
An effective way to support your students’ understanding of the
relationships between the Earth and the Sun is to carry out a practical
activity that explores shadows. Before you carry out this activity, it is
advisable to introduce your students to the concept that the Earth both
spins and orbits the Sun. Working through the activity ‘Being the Earth,
the Sun and the Moon’ in Section 1 will familiarise your students with
this concept.
Read through the activity description and create a more detailed lesson
plan that is suited to the ages and abilities of the students in your class.
A lesson plan template is provided in Resource 3 of TDU 1, Using
brainstorming to elicit prior knowledge: sound and musical instruments.
Making a Sundial
1 Choose a sunny spot in an outdoor area that is free of shadows.
2 Organise your students into small groups.
3 Choose a tall object that will stand up by itself or ask the students
to push a thick stick or pole into the ground. Whatever you use,
the object needs to cast a measurable shadow.
4 Tell your students to mark the shadow that is created by the tall
object or stick, or by placing a small stone at the shadow’s tip or
by making a chalk mark. Write the time on the stone, or next to
the chalk mark.
8
2 Observing shadows
5 Repeat this activity throughout the day.
6 Ask your students to describe what is happening to the shadows
over time. Ask them to explain why they think the shadows are
changing.
7 The following day, show your students how to use the sundial to
tell the time. Take your students outside at half past the hour and
ask them to tell you what the time is.
8 In the classroom, ask your students to write a report, with
pictures, of what they observed. This can be displayed in the
classroom.
9 Ask your students to draw a diagram that explains how shadows
are created.
Extending the activity
This activity can be extended by asking your students to measure the
length of each shadow and to create a bar chart that represents the
changes that occur. Can the students identify any patterns in the data?
Can they explain any of the patterns that they find?
Your students could then move on to investigating what shadows might
look like in different parts of the world. What do shadows look like at the
north and south poles, for example?
Pause for thought
.
What went well during the activity, and what would you change for
the next time you teach this topic?
.
Could your students explain why shadows change throughout the
day?
.
What did your students need support with?
.
How did you challenge your more able students?
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
3 Observing the Moon
Pause for thought
Thinking back to Section 1, what misconceptions did you have about the
Moon when you were a child? If your students had similar
misconceptions about the Moon, what would you need to teach them in
order to change their understanding? How might you go about doing
this?
Many cultures around the world have created fascinating stories and myths
to explain the mystery of the changing appearance of the Moon. Some of
these stories remain part of our culture and continue to be shared today. Our
understanding of the Moon has nevertheless been transformed since the first
humans landed there in 1969.
The everyday language that we use to talk about the Moon can be
misleading too. When asked to describe the Moon, younger students may
talk about ‘the bright moonlight’ and the ‘shining Moon.’ They may find it
difficult to understand that the Moon has no light of its own, and that the
moonlight we see is in fact a reflection of the Sun’s light. Most students will
have observed the Moon passing through its different phases, and may be
familiar with the terms ‘new Moon’, ‘crescent’, ‘full Moon’, etc. However,
they may believe that these phases are created by the Earth casting a shadow
on the Moon, rather than light being reflected to the Earth from the Moon at
different angles.
These concepts can be challenging to teach, especially if classroom resources
are limited. The simple activity below may help your students develop a
better understanding of why the Moon appears to radiate light and to change
in size and shape.
Observing the Moon
For this classroom activity you will need a torch and a large white ball.
1 Before beginning the activity, block out as much light as possible from
the classroom. Use rugs, curtains or pieces of cloth to block light from
the windows and doors.
2 Create a large space in the class by moving the chairs and desks.
3 Ask the students to sit close together in a circle near the centre of the
room. You may need to create an inner and outer circle, depending on
how big your class is. Explain that the circle they are in represents the
Earth and that the torch and ball represent the Sun and the Moon
respectively.
10
3 Observing the Moon
4 When all the lights are switched off, hold up the ball and ask the
students if they can see it clearly. Ask them if the ‘Moon’ is radiating
light.
5 Ask one student to hold the torch and switch it on. Place the ball in the
beam of light from the torch. Explain that the ‘Moon’ is not lighting up
but is reflecting light from the ‘Sun’.
6 Ask the students to sit still, look straight ahead and not to follow you
with their eyes. Ask the student with the torch to remain still. Then move
around the circle with the ‘Moon’ stopping at regular intervals to allow
students time to observe what they see. Explain that you are the ‘Moon’
orbiting the ‘Earth’.
7 Ask the students ‘Does the Moon change shape as it passes?’ and ‘How
much of the Moon can you see?’ (all of it, half, not all, etc.).
8 Rearrange the students and repeat the activity several times so that all the
students have the opportunity to make clear observations.
9 As you are orbiting the ‘Earth’, keep the same part of the ‘Moon’ facing
towards the students. Explain that the Moon is in synchronous rotation
with the Earth. This means the same part of the Moon always faces the
Earth.
After completing this demonstration, ask your students to draw a diagram of
the Sun, the Moon and the Earth, using arrows to indicate how light is
reflected from the Sun.
A torch and ball can also be used to demonstrate that we experience daytime
when our part of the Earth faces the Sun, and that the parts of the Earth
facing away from the Sun are experiencing night time.
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
4 Teaching the phases of the Moon
Pause for thought
Thinking about your past teaching practice, how have you explored the
changing phases of the Moon with your students? Was it a subject that
you found easy to teach?
Case Study 1: Mrs Latika teaches her class about
the phases of the Moon
Mrs Latika, a teacher of Class III, asked her students to brainstorm what
they knew and understood about the Moon. When she reviewed her
students’ responses, she realised that they had some awareness of how
the Moon appears to change, but were not able to explain why this
happened. Mrs Latika planned a series of short activities to help her
students understand the different phases of the Moon. Read how she
went about this.
I began the lesson by giving each of my students a small piece of card
on which I asked them to draw the Moon. After five minutes, I asked
them to swap their drawing with a partner and compare it with their own.
My students quickly realised that they had all drawn the Moon in
different ways. I asked them why they thought this was. After some
discussion, we agreed this was due to the changing nature of the Moon.
I then read my students a short poem that introduced the idea of the
waxing and waning of the Moon [Figure 1]. In the poem, the Moon feels
cold and asks its mother to sew it a shirt. The Moon’s mother explains
that she is unable to do so as the Moon keeps changing its shape. She
says that at times it is as thin as a finger (crescent Moon) and at times
as large as a football (full Moon), and there are times when it is not
visible at all (new Moon).
Figure 1 The story of the Moon and its mother.
12
4 Teaching the phases of the Moon
After discussing the poem and relating it to my students’ observations
as depicted in their drawings, I used a model to explain how the Earth
and Moon move relative to the Sun [Figure 2]. As I moved the Moon, I
explained that it always faces the Earth and that the Moon appears to
change shape as light is reflected toward the Earth at different angles. I
drew a diagram on the blackboard to demonstrate the Sun’s light being
reflected from the Moon.
Figure 2 Making a model of the Earth and the Moon.
I then organised my students into groups of four and gave each group a
set of cards with the Moon’s different phases on them. I asked my
students to agree the sequence that the cards should go in. After some
discussion, I displayed the correct sequence of the Moon’s phases on
the board. I asked my students to compare this to theirs and to help me
label each phase on the board. Finally, I asked each group to depict the
various phases of the Moon using paper, pens and paint. The
photograph below [Figure 3] shows one way a group of students
completed this task.
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
Figure 3 The phases of the Moon.
Mrs Latika reflects on the lessons
I carried out these activities over two lessons to ensure that my students
had enough time to complete each task. I felt that using the poem
helped to engage my students’ interest while at the same time
stimulating a discussion about their own observations of the Moon.
I felt that the most successful part of the lesson was asking the students
to create a representation of the Moon in its various phases. Each group
presented their ideas in a unique and meaningful way. If I was to teach
this lesson again, I would include more initial preparatory work on how
the Earth and the Moon move relative to the Sun.
14
5 Games and quizzes
5 Games and quizzes
Continuous and comprehensive evaluation (CCE)
Games and quizzes can present excellent opportunities for teachers to
assess students’ knowledge and understanding in an enjoyable way.
Students can play games and quizzes on their own or with their peers.
Some ideas and suggestions for games-based learning can be found in
TDU 11, Making and using games to support learning: understanding
electricity.
Quiz about the Earth, the Sun and the
Moon
The following quiz gives you an idea of the sorts of questions you could ask
to assess your students’ basic understanding of the Earth, the Sun and the
Moon.
This quiz can be adapted to suit the learning needs of your students.
Questions from the quiz can be hidden around the classroom or in an
outdoor area to engage and motivate students further. Quizzes such as these
should be used in combination with other forms of assessment. Ideas for
assessing your students’ progress can be found in the CCE sections of other
units.
Q1 What shape are the Earth, the Sun and the Moon?
Q2 Which is the largest: the Earth, the Sun or the Moon?
Circle the correct answer.
.
The Earth.
.
The Sun.
.
The Moon.
Q3 How long does it take for the Earth to travel once around the Sun?
Q4 How long does it take for the Moon to travel once around the Earth?
Q5 How long does it take for the Earth to complete one rotation?
Q6 Which part of the Earth is in daylight?
Circle the correct answer.
.
The part facing the Sun.
.
The part facing away from the Sun.
.
The part facing the Moon.
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TDU 8
Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
Q7 Which of these statements is not true?
Circle the answer that is not true.
.
The Sun rises in the east and sets in the west.
.
The Sun is highest in the sky at midday.
.
The Sun moves westwards around the world.
Q8 Circle the correct statement.
The Moon appears to change shape because …
.
It gets bigger and smaller.
.
We only see the part of the Moon that is lit by the Sun.
.
The Earth sometimes casts a shadow on it.
Q9 Imagine you are standing in the playground. When would your shadow be
at its shortest?
Circle the correct statement.
.
At sunrise.
.
At midday.
.
At sunset.
Q10 What would you call an object that moves around a planet?
Circle the correct answer.
.
A star.
.
A satellite.
.
A comet.
Q11 What phase is the Moon in this picture?
Circle the correct answer.
16
.
Full Moon.
.
New Moon.
.
Waxing crescent.
6 Summary
6 Summary
Students’ understanding of the relationships between the Earth, the Sun and
the Moon may include various misconceptions. Sometimes it may be
necessary to create a simulation of events – through drama, for example – so
that students can gain a deeper understanding of why things happen. This
unit has presented some ideas for exploring the movements of the Earth, the
Sun and the Moon through classroom and outdoor activities.
The phases of the Moon are a familiar natural phenomenon that can be
approached by first considering the nature and characteristics of shadows
cast by sunlight. Observing and describing shadows, and using classroom
models, can lead naturally on to describing and identifying the phases of the
Moon.
Creating opportunities for students to observe and record the natural
phenomena around them can help them to realise the connections between
the Earth, the Sun and the Moon.
17
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
7 Resources
Resource 1: The formation of shadows
Light travels in straight lines. A shadow occurs when an opaque object
blocks light from the Sun or some other light source. Observing the
behaviour of shadows is an easy way to investigate some of the properties of
light.
Points to understand include the following:
.
A shadow of an object will move due to either the motion of the object
or of the light source.
.
Even seemingly transparent objects can form shadows if they absorb or
reflect some of the light striking them.
Figure R1.1 Vocabulary associated with shadows.
Resource 2: Phases of the Moon
The appearance of the phases of the Moon in different
parts of the world
It is important to understand that the visible appearance of the phases of the
Moon depends on where you are on the Earth, and particularly whether they
are viewed from the northern or southern hemisphere (Figure R2.1). The
Primary Homework Help website explains this with suitable photos and
advice for teaching the subject. When searching for resources on the web,
take particular care to note the hemisphere from which photos or illustrations
have been taken.
18
7 Resources
Figure R2.1 Phases of the Moon as viewed from the northern and southern
hemispheres.
Explaining the phases of the Moon
As the Moon circles the Earth, its shape appears to change. This is because
different amounts of the illuminated part of the Moon are facing us (Figure
R2.2). The shape varies from a full Moon (when the Earth is between the
Sun and the Moon) to a new Moon (when the Moon is between the Sun and
the Earth).
Figure R2.2 Explanation of the phases of the Moon, as viewed from northern
hemisphere. The Sun is at the top.
The lunar phase refers to the shape of the illuminated (sunlit) portion of the
Moon as seen by an observer, usually on the Earth’s surface. The lunar
phases change cyclically as the Moon orbits the Earth, according to the
changing relative positions of the Earth, Moon, and Sun. The half of the
lunar surface facing the Sun is always sunlit, but the portion of this
illuminated hemisphere that is visible to an observer on Earth can vary from
about 100% (full Moon) to 0% (new Moon).
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Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
The phases of the Moon simplified
It is probably easiest to teach the Moon cycle in this order:
.
New Moon: As shown in Figure R2.2, the new Moon occurs when the
Moon is positioned between the Earth and the Sun. The three objects are
in approximate alignment (why this is ‘approximate’ is explained below).
The entire illuminated portion of the Moon is on the back side of the
Moon – the half that we cannot see.
.
Full Moon: At a full Moon, the Earth, Moon and Sun are again in
approximate alignment (just as the new Moon), but the Moon is on the
opposite side of the Earth, so the entire sunlit part of the Moon is facing
us. The shadowed portion is entirely hidden from view.
.
First quarter and third quarters: Both of these are often called a ‘half
Moon’ and occur when the Moon is at a 90° angle with respect to a line
between the Earth and the Sun. So we are seeing exactly half of the
Moon illuminated and half in shadow.
Once you understand those four key Moon phases, the phases between
should be fairly easy to visualise, as the illuminated portion gradually
transitions between them.
.
Crescent and gibbous, waxing and waning: An easy way to remember
and understand those ‘in-between’ lunar phase names is by defining four
words: crescent, gibbous, waxing and waning. The word ‘crescent’ refers
to the phases where the Moon is less than half-illuminated. The word
‘gibbous’ refers to phases where the Moon is more than half-illuminated.
‘Waxing’ essentially means ‘growing’, or expanding in illumination, and
‘waning’ means ‘shrinking’, or decreasing in illumination.
Thus, you can simply combine the two words to create the name of the
phase, as follows. After the new Moon, the sunlit portion is increasing,
but less than half, so it is waxing crescent. After the first quarter, the
sunlit portion is still increasing, but now it is more than half, so it is
waxing gibbous. After the full Moon (maximum illumination), the light
continually decreases, so the waning gibbous phase occurs next.
Following the third quarter is the waning crescent, which wanes until the
light is completely gone and become a new Moon.
Resource 3: The Hindu calendar and
festivals
The name for a Hindu calendar is a panchānga. Along with other
information, panchāngas especially record the movements of the Sun and the
Moon. There are 30 lunar days in a lunar month and they are sequentially
numbered starting from both the new Moon and the full Moon. Thus, in the
Moon’s waxing phase, the first lunar day is called a new Moon or amavasya,
the next lunar day is called the first tithi, the next lunar day is called the
second tithi and the next is called the third tithi, and so on until the 14th
lunar day. The day after the 14th is called full Moon (purnima).
20
7 Resources
From this point the numbering sequence starts over again. The day after the
full Moon is the first tithi, the next day is the second tithi, and so on. The
important difference is that the second set of tithis belong to the waning
phase of the Moon, while the first set belongs to the waxing phase.
Afterwards, the cycle repeats itself. In this way, 30 tithis make up a lunar
month, which is known as a masa.
The Hindu year contains 12 lunar months named after the nakshatra in
which the Moon is full. These months are listed in Table R3.1.
Table R3.1 Hindu lunar months.
Chaitra
March to April
Vaishakha
April to May
Jyaishtha
May to June
Ashadha
June to July
Shravana
July to August
Bhadrapada
August to September
Asvina
September to October
Karttika
October to November
Margasirsha
November to December
Pausha
December to January
Magha
January to February
Phalguna
February to March
The regions of India celebrate many different festivals. Some of them are
listed in Table R3.2. In general, festivals are celebrated during the bright or
waxing side of the lunar month (shukla paksha). Festivals that deal with
ancestors generally take place during the dark or waning phase of the lunar
month (krishna paksha).
Table R3.2 Major Hindu festivals.
Hindu festival
Hindu lunar day of observance
Makar Sankranti or Pongal
Makar Sankranti or Pongal marks the
transition of the Sun into Makar rasi. It marks
the gradual increase of the duration of the
day.
Pongal is the first day of Uttarayana and
coincides with the beginning of the Tamil
month of Thai.
Vasant Panchami
Fifth day of the waxing Moon of Magh (Hindu
calendar)
Maha Shivaratri
Thirteenth night of the waning Moon of Magh
(Hindu calendar)
Holi
Full Moon of the Phalgun month (Hindu
calendar)
Gudi Padwa
First day of waxing Moon of Chaitra (Hindu
calendar)
21
TDU 8
22
Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
Bihu
Vaisakha, the first month of the Hindu
calendar
Vat Pournima
Full Moon of Jyeshta (Hindu calendar)
Guru Purnima
Full Moon of Ashadh
Raksha Bandhan
Full Moon of Shravana
Krishna Janmaashtami
Eighth day of waning Moon of Bhadrapad
Ganesh Chaturthi
Fourth day of the waxing Moon of
Bhadrapada
Navarathri and Bathukamma
First nine nights of the waxing Moon of
Ashvin
Vijayadashami
Tenth day of waxing Moon of Ashvin
Deepavali
New Moon of Ashvin
8 Related units
8 Related units
The following units are particularly closely linked with the content of this
unit.
.
TDU 5, Using questions to extend students’ understanding of forces:
This unit explores the use of questioning to promote students’
understanding and encourage reflective thinking. Good teacher
questioning will help to support and develop students’ observational
skills.
.
TDU 13, Practical investigations: exploring seed germination:
Observing is a fundamental part of the scientific method, which is
explored in more detail in this unit.
23
TDU 8
Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
References
Shadows and sunlight
Greenwaldt, P. (2013) ‘Identifying the sun as a source of light by observing
shadows’ (online), Minnesota Science Teachers Education Project, 29 May.
Available from: http://serc.carleton.edu/sp/mnstep/activities/35629.html
(accessed 30 January 2014).
Jones, C., Ruiz, T, Waters, S. and Breen, J. (1998) ‘The Earth’s rotation’
(online), Chapter 1, Everyday Classroom Tools, Smithsonian Institute. Available
from: http://hea-www.harvard.edu/ECT/the_book/Chap1/Chapter1.html
(accessed 30 January 2014).
NASA (2013) ‘What makes shadows? Observing and drawing shadows’
(online), Solar System Exploration. Available from: http://solarsystem.nasa.
gov/educ/lesson-view.cfm?LS_ID=890 (accessed 30 January 2014).
Plesser, R. and Heffernan, J. (2003) ‘Light and shadows: shadow-tracing’
(online), Chapter 7, The Earth and Sun: Investigations for the Third Grade,
LEARN NC. Available from: http://www.learnnc.org/lp/editions/earth-sun/
6568 (accessed 30 January 2014).
The Moon and its phases
Barrows, M. (2010) ‘The Moon: tips for moon watching & moon times’
(online), Primary Homework Help. Available from: http://resources.
woodlands-junior.kent.sch.uk/time/Moon/tips.html (accessed 30
January 2014).
Barrows, M. (2013) ‘The Moon: does the Moon look the same in other
countries?’ (online), Primary Homework Help. Available from: http://www.
primaryhomeworkhelp.co.uk/moon/hemispheres.html)
Bunyi, A. (2011) ‘Teaching Moon phases’ (online). Available from: Scholastic,
Inc., Teachers website: http://www.scholastic.com/teachers/top-teaching/
2011/03/ready-edit-teaching-moon-phases-seems-be-one-those-skillstaught-across-grade-l (accessed 30 January 2014).
MoonConnection.com (undated) ‘Understanding the moon phases’ (online).
Available from: http://www.moonconnection.com/moon_phases.phtml
(accessed 30 January 2014).
Science NetLinks (undated) ‘Sky 4: the Moon’ (online). Available from: http://
sciencenetlinks.com/lessons/sky-4-the-Moon/ (accessed 31 January 2014).
The Hindu calendar and festivals
Das, S. (undated) ‘Purnima & Amavasya: Hindu fasts’ (online), About.com.
Available from: http://hinduism.about.com/od/festivalsholidays/a/
Purnima-Amavasya-Hindu-Fasts.htm (accessed 30 January 2014).
Dasa, S.N. (2007) ‘A Hindu primer’ (online), Devasthanam. Available from:
http://www.sanskrit.org/www/Hindu%20Primer/hindufestivals.html
(accessed 30 January 2014).
Wikipedia (2013) ‘List of Hindu festivals’ (online). Available from: http://en.
wikipedia.org/wiki/List_of_Hindu_festivals (accessed 30 January 2014).
Scientific method
Oh, P.Y. (undated) ‘Hypotheses’ (online), Drexel University. Available from:
http://www.pages.drexel.edu/~pyo22/students/hypothesis.html (accessed
31 January 2014).
24
References
Science Made Simple (undated) ‘Understanding and using the scientific method’
(online). Available from: http://www.sciencemadesimple.com/
scientific_method.html (accessed 31 January 2014).
25
TDU 8
Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
Acknowledgements
The content of this teacher development unit was developed collaboratively
and incrementally by the following educators and academics from India and
The Open University (UK) who discussed various drafts, including the
feedback from Indian and UK critical readers: Jane Devereux, Kavita Grover
and Christine James.
Except for third party materials and otherwise stated, this content is made
available under a Creative Commons Attribution-ShareAlike licence:
http://creativecommons.org/licenses/by-sa/3.0/
The material acknowledged below is Proprietary, used under licence and not
subject to any Creative Commons licensing.
CCE logo: http://www.cbse.nic.in/.
Figure 1: Ramdhari Singh ‘Dinkar’, The Moon and its Mother in Udaan
Hindi Pathmala-grade 3, Cardova learning series http://www.cordova.co.
in/.
Figures 2 and 3: photographs by Christine James for TESS-India/The Open
University.
Resource 1.1: http://www.physics-chemistry-class.com/light/
formation-of-shadows.html.
Resource 2.1: http://www.primaryhomeworkhelp.co.uk/.
Resource 2.2: http://en.wikibooks.org/wiki/
High_School_Earth_Science/The_Sun_and_the_Earth-Moon_System.
Made available under http://creativecommons.org/licenses/by-sa/3.0/.
Every effort has been made to contact copyright owners. If any have been
inadvertently overlooked, the publishers will be pleased to make the
necessary arrangements at the first opportunity.
26
Transcript
Transcript
Narrator:
In this video the teacher gets her students to use the school grounds
to observe shadows at different times of the day and discuss how
they are formed.
Teacher:
I just want to ask you one thing. Do you see something following you
throughout the day?
Students:
Shadows.
Teacher:
It follows you?
Students:
Yes ma’am.
Teacher:
Wherever you go?
Students:
Yes ma’am.
Teacher:
Yes?
Students:
Yes ma’am.
Teacher:
Alright. So, we will be observing shadows today and we will go out,
we will see if there is any change in the size and shape, or position of
shadows, and we will be studying this at different times of the day
like we will go and see how our shadow is in the morning or how the
shadow of an object is in the morning. We will go at 10 o’clock, and
then afternoon we will go at 1 o’clock. Will that be interesting?
Students:
Yes ma’am.
Teacher:
Are you all interested in observing the shadows?
Students:
Yes ma’am.
Teacher:
No complaining, no fighting, okay. Listen to each other. You will take
up this first position. Here you can take up this pole. Group II, four of
you come here, four children, see the position of the Sun. Group III,
that’s your brick.
Teacher:
[Teacher speaks in Hindi]
Students:
Time 8:25 and length 56 cm.
Students:
[Student speaks in Hindi]
Teacher:
Come on we will go for the next activity now.
Students:
Oh! It’s shorter. [discussing] 9:55 a.m. 33 cm. [discussing]
Students:
[discussing] Yeah, what is the centimetre? It’s 24. It’s 17 or 16? It’s
24 cm.
Student:
What is the time?
Student:
12.59 pm.
27
TDU 8 Developing observational skills: exploring the relationships between the Earth, the Sun and the Moon
Students:
[discussing]
Student:
The shadow was so big, and now it's so small.
Teacher:
So, how was this activity on shadows children?
Students:
Ma’am nice.
Teacher:
Good, nice. What is it that is so interesting about this shadows that
you have been seeing since morning?
Student:
Ma’am, in the morning first we see that the shadow is longer, then we
come in, then we go, then we come in afternoon the shadow is
smaller and now after we come, the shadows is too smaller.
Student:
Ma’am it is because of the Sun. Ma’am the Earth moves.
Teacher:
The Earth moves.
Student:
Yes, ma’am. Sun is at its own place, but the Earth is revolving, that is
why early in the morning we see the Sun here, but now it is here and
it also changes the position of the shadow also because early in the
morning, the Sun was over there and shadow was here, but now it is
here.
Teacher:
All right, and where is the Sun when the shadow is there, where is
the Sun?
Student:
Ma’am there.
Teacher:
This morning children, the Sun was this side and where were your
shadows formed?
Student:
Ma’am that side.
Teacher:
And at 10:30 when you came, I saw the Sun here, was the Sun here?
Students:
Yes ma’am.
Teacher:
And where was the shadow formed?
Students:
Ma’am there …
Teacher:
Right opposite, okay? Today we were playing with Sun, we were
making observations out in the Sun, but if you go home, if you light a
candle or a bulb, you could use any source of light and you could
again observe the behaviour of the shadows, alright?
Narrator:
Giving clear instructions about what students have to do outside the
classroom ensures that other classes are not disturbed.
Working outside doing longitudinal studies of real phenomena helps
the students to see patterns in their data.
28