Every field of study has technical terms that are used by people within that field. Newcomers to the field may not be familiar with the terminology used by others and may find themselves unsure of what certain words and terms mean. This is where a Glossary comes in handy. This Glossary is designed to help both students and teachers understand new or unfamiliar vocabulary or specialized terminology in this field of study.

Below are some ideas on how you could use the Glossary with students. Students could:

• Create new glossary entries for terms not on the list.
• Group glossary terms into categories and explain the reasons for their grouping of the terms.
• Create labeled drawings to illustrate different terms.
• Add to the definitions based on further research.
• Compare the definitions in this glossary to definitions in other web-based glossaries.
• How are they similar and different? Have them think about why this may be the case.

Constellation: an area in the sky where people have looked up and seen a picture created by the stars.These patterns are helpful in finding our way around the night sky.

Circumpolar: circling one of the Earth's poles. For example, in Canada this means circling the North Pole.

Eclipse: an event in which one body's shadow falls on another body.

Ecliptic: the plane of the solar system

Gas Giant: a large planet consisting mostly of hydrogen and helium. Gas giants do not have a solid surface. Planets do not produce light, but reflect the light of the sun.

Light Year: the distance light travels in a year, roughly 10,000,000,000,000 km

Magnitude of Stars: a system of classifying stars according to their brightness, running from negative (the brightest) to positive (less bright) values.

Nebula: a cloud of gas and dust in space or surrounding a star. Nebulas are often where stars are born and can be a place where a star has died.

Plasma Tail: a stream of high temperature gas consisting entirely of ions, or atoms that have lost one or more electrons, blown off a comet by the solar wind. Plasma, or ion tails always point away from the Sun.

Red Giant: an expanding old star. The surface of a Red Giant cools off as it expands.

Refraction: the focusing of a straight beam of light through a lens.

Revolution: the motion of one body around another. For example, the Earth revolves around the Sun once per year.

Rotation: the motion of spinning on an axis or centre, like a top. For example, the Earth rotates once per day on its axis.

Solar Wind: a blast of particles and magnetic fields flowing out from the Sun at speeds of up to 1000 km/sec.

Spectrograph: an instrument used to arrange the light coming from an object by wavelength. Spectra are useful in determining which elements are found in an object.

Star Cluster: a group of stars located near each other in space. Open clusters consist of newer stars that have just been formed in the same nebula. Globular clusters contain many more stars than open clusters and are much older in age.

Supernova: the explosion created when, with no support, the outer parts of a star collapse, and the star explodes and outshines all the other stars in its galaxy combined.

Variable Star: a star that changes in brightness, often over a set period of time or regular cycle.

White Dwarf Star: the cooling core of a star that has run out of fuel.

Yellow Dwarf Star: a small, main sequence star like our own Sun.