Homi Bhabha Centre for Science Education, TIFR

For model-gesture-diagram links see:

Padalkar, S. & Ramadas, J. (2010). Designed and spontaneous gestures in elementary astronomy education. International Journal of Science Education. DOI: 10.1080/09500693.2010.520348

Gesture no. Context or Concept + (Accompanying tools) Gestures and actions
Part I: Round Rotating Earth
1 Night sky observation Tracing star patterns by fingers/ hands.
2 Determining position (direction + degrees above horizon) of a star
3 Showing round earth by hand
(Photographs of the earth, Globe)
Moving hands with palms open to show sphere.
4 Showing round part of spherical earth on circular earth on the blackboard (fig.3) Moving arm with open curved palm to show half sphere of the earth coming out of the blackboard, imagining circle as circumference of the earth and other half sphere inside the black board.
5 Understanding flatness of the earth (Balls of different sizes) Holding or imagine to be holding a very small to a very large ball and observe the change in curvature on palm and then arm.
6 Axis of rotation (notebook, pencil box, other objects) Rotating objects and body parts and identifying axis of rotation.
7 Axis coming out of, or going inside the plane of diagram (fig.3b) Index finger pointing inside or outside, perpendicular to the diagram.
8 Gestures in Play .Galileo. to mimic the earth's rotation and perspective changes (rotating chair) Sitting on a rotating chair to see occurrence of day-night.
9 Gestures in Play .Galileo. to mimic the earth's rotation, perspective changes and up-down (apple, toothpick) Assuming apple to be the earth, and radially attached tooth-pick as a human. Rotating the apple around the axis passing through its stem to see day-night.(Image)
10 Showing motion of the earth for the axis in the given diagram (Axis either in the plane of diagram (fig.3a) or perpendicular to it (fig.3b)) a. Showing a vertical index finger in horizontal circle in front of blackboard (or in half circle, with axis as center)
b. Moving a horizontal index finger in a vertical circle around a point on the blackboard.
11 Determining directions (Down, Up, North, South) of a person on the globe or in diagram of the earth (fig.3a)
12 Determining directions (East, West) of a person on the globe or in diagram of the earth (fig.3b) East: Orienting orienting one's self parallel to the North-facing person in the diagram so that the right hand indicates East in the diagram, OR find the direction of motion of the earth (west to East) with right hand thumb rule. East is indicated by the direction of curl of the fingers (Gesture no. 13).
West: Opposite to East
13 Right hand thumb rule for determining direction of motion of the earth Gesture of thumbs-up. In (fig.3) align thumb in the direction of axis and pointing towards the north pole, then curl the fingers to show the direction of earth's rotation (or revolution)(West to East).
14 Shadows and beams
(cardboard cutouts, sunlight. torch, gnomon)
shadow created by fingers to shadow of the body
15 Tracing ray diagrams Tracing path of light-beam/ ray by open palm (representing wave front) / finger on board
16 Pair Day night (globe/ geosynchron) One student becomes the earth, another student (or object) becomes the sun. Mark the objects around in egocentric frame (front/ back/ left/ right). Observe how the field of vision and positions of objects changes due to rotation from right to left.
17 Tracing path of the sun by extended arm. Simulating motion on different latitudes Move the stretched hand in vertical or inclined half circle from East to West. Inclination towards north or south depending upon whether one imagines herself in the southern or northern hemisphere.
18 Position of the pole-star remains the same Fix a point vertically overhead on the ceiling and check whether its position changes while rotating around the vertical body-axis.
Part II: Sun-Earth System
19 Measurement
(6-inch scale, foot-scale, meter-scale)
Measuring 1mm to few meters by using body parts.
20 Angle
Rotating hand from 0° to 180°
21 1, 2 & 3 dimensions
(model of 3 axes, other daily examples, locating an address)
Length: walking, Area: flat palm, Volume: Filling up
22 Pair Rotation + Revolution gives motion of the earth Only rotation (facing changes); only revolution (facing does not changes); 1 rev + 1 rot; 1 rev+ 2 rot; 1 rev + 4 rot; imagine 1 rev + 365 rot.
23 Shape of orbit of the earth (nails, thread, thermocol sheet) Drawing ellipses using 2 nails: A series of diagrams which give kinesthetic feedback.
24 Understanding ellipse with circle and line as extreme cases Making circle, ellipse and line by joining palm.
25 Perspective view of circle (bangle, bucket, other circular objects) Observing loop made by thumb and index finger (or other objects) from top, side and oblique view.
26 Angle made by the earth's axis with the ecliptic plane Show axis tilt by forearm bent at elbow.
27 Plotting the sun-earth distance on the ground (marbles, measuring tape, thread for measurement, chalk) Find out ratios of distances considering an earth of diameter 1cm and plot them on the ground.
28 Group of 10 Solar system (picture of solar system, Chart of distances and speeds) Each student becomes one planet and revolves around the student who is the sun, taking account of the relative speeds.
29 Group Changes in the night sky over the year (Calendar) One student becomes the sun, another becomes the earth and revolves around the sun. All other students become different nakshatras representing a star background. Students predict which Marathi month and which solar nakshatra is on, depending upon the position of the earth.
30 Intensity changes as a function of angle of incidence Put your hand above hot lamp (or in rain) in different orientation, to sense that collection of heat (or water) depends on angle of incidence.
31 Trace path of the sun in different seasons Trace a semicircle with a stretched arm making different angles with horizon depending upon the season.
Part III: The Sun-Earth-Moon System
32 Angle Pointing and tracing acute, right and obtuse angles in room, finding out parallel lines.
33 Pair We see only one face of the moon Only rotation, Only revolution, Both rotation and revolution together.
34 Phases of moon and eclipses Rotating the ball around one's head in tilted orbit, with a strong light source on one side.
35 Pair Phases of moon Replace the ball by friend and watch friend's face (this sequence is explained in Subramaniam and Padalkar, 2009).
36 Tilt in the moons orbit explains why there are no eclipses on all full and new moon nights Showing tilt of moon's orbit by moving extended arm around (with or without ball in the hand).
37 Pair Phases of moon and eclipses Moving around the friend considering one's head as the moon and the friend's head as the earth
38 Triad Sun-Earth-Moon system Moon moving around the earth while earth moving around the sun.
39 Pair Moon takes 2 extra days to complete the orbit with respect to the sun than with respect to the background sky Moon moves around the earth while the earth forwards (considering the earth's orbit to be almost straight and the sun to be very far away).
40 Group Connection between apparent motion of the moon and indigenous months and nakshatras
Moon moving around the earth against the background of stars behind (Arrangement similar to gesture no. 29).