Remember the Egg!
(from Astrogram May/June 1998)
Allan Meyer, Bay Area Project ASTRO astronomer
Most students, or for that matter most people, have had little or no experience looking through a good amateur or professional telescope. However, many people have seen very colorful images of the planets, containing a wealth of details. For many people, their first view of a planet through a telescope can be quite disappointing, since they only see at first glance a small white spot. The eye is an excellent, perhaps unmatched detector of subtle, extremely low contrast details, but the mind of the observer must be ready and willing to perceive such low-level sensory input. Like listening for very faint sounds or smelling the differences between wines, this may require concentration and perhaps also some training or practice. As an attempt to provide a little of such training, with Mary’s permission and help I conducted the following activity.
- 1 hardboiled egg (with a green dot on one side) per student
- 1 empty egg carton per small group
- egg identification worksheets as illustrated below
- Overhead beam projector, spotlight, or flashlights
A hard boiled egg was provided to each student. A worksheet was also provided, which contained four outlines of the shape of an egg as viewed from two opposite sides, and as viewed end on, namely two circles. The students were asked to carefully inspect their eggs, looking for any distinctive features on the sides or on the ends that they could draw on their worksheets. The goal for each student was to find features on the egg that they could draw on their “egg identification sheet”, such that someone else would be able to match the egg to the drawing, and therefore determine the original “owner” of the egg. The overhead beam projector and a spotlight were made available for close inspection of eggs under lighting that brings out very subtle features (bumps, valleys, grooves, spots, cracks). I noticed a few students started to just make random dots to represent a speckled or rough appearance, and the class was reminded to concentrate on trying to make accurate drawings of a few distinctive features. Many of the students were able to find quite subtle and distinguishing features, and reasonably accurately represent their appearance and location on their worksheets.
The class had been divided into groups of 4 or 5. When all of the students in a group had finished their drawings, their eggs were placed in an egg carton, their drawings collected, and then the eggs and drawings were passed on to another group of the same size. The two groups might swap eggs and drawings, or several groups might be involved in transfer of sets. A group receives a carton of eggs and a set of drawings, and then attempts to match up the drawings and the eggs. When they think they have established which drawings represent which eggs, they write the names from the drawings in the egg carton, placing the egg in its assigned spot. Finally the carton containing proposed identifications is returned for verification. In this case, about half of the identifications were correct.
After this I reviewed the motivation for this exercise – to learn how to see, describe and draw faint or subtle features on an object which is thought of by most people as having a smooth, featureless surface. I concluded by telling the students that I hoped they would understand when the time did come to look through a telescope and I asked them to “Remember the egg!”