Observing the night sky

Class practical

Observations of the stars, planets and the Moon for students to make.

Apparatus and Materials

• Camera with B (open shutter) setting

Health & Safety and Technical Notes

Caution students about where and when (and with whom) they make their observations of the night sky, so that they do not put themselves at risk. If appropriate, inform parents/guardians.

Read our standard health & safety guidance

Procedure

1. Ask students to observe the sky at least twice in one evening, with an interval of about two hours between observations. (It will help if pictures of a few easy-to-identify constellations are available before the observing time, so that students will recognize them and can direct their observations towards them.)
2. Ask students to watch the Moon and to note its position relative to the stars. Then, one or two hours later, look again and note the new position of the Moon relative to the stars. The Moon appears to travel across the star pattern.
3. Extend the previous experiment to a month. Note the position of the Moon at the same hour on each possible night for a month. The observations should relate to the stars, and also to the position in the sky relative to the horizon. Ask students to draw the phases of the Moon throughout the monthly cycle. (There will be times when the Moon is invisible during the night and will only be seen during the day. The rising and setting of the Moon can often be found from diaries or the newspapers.)
4. Show students the brightest planets - Venus, Jupiter and, possibly, Saturn.

Teaching Notes

• Students will need to be prepared for this observation in anticipation that a clear starry night appears. Normally the best times are during winter when the skies are predicted to be clear and a frost is forecast. Viewing the sky away from the city lights is recommended. These observations will probably have to be done at home for many students.
• A compass is helpful so that students know in which direction they are looking.
• A record of observations should be made.
• For step 1 it will help if pictures of a few easy-to-identify constellations are available before the observing time, so that students will recognize them and can direct their observations towards them.
• In step 2 the Moon appears to travel across the star pattern.
• For step 3. there will be times when the Moon is invisible during the night and will only be seen during the day. The rising and setting of the Moon can often be found from diaries or the newspapers.

This experiment was safety-tested in April 2007