Astrodome Mobile Planetarium

Please do the Geography Quiz BEFORE going over these terms with the children.

In preparation for the ASTRODOME visit it would be useful if you could spend some time with the children discussing the following terms and concepts.

ATMOSPHERE The gas envelope which surrounds our planet from the ground up to about 500 km - that's where space stars. In our present atmosphere oxygen and nitrogen form more than 99% of the gases.
CRETACEOUS PERIOD The final part of the Mesozoic Era dating from 135 to 65 million years ago. This period saw the first appearance of flowering plants, the extinction of the dinosaurs and many other animals, and extensive deposits of chalk.
CRUST The outermost rocky layer of our Earth. It is in the form of plates (see below) with a thickness varying between 6 and 40 km.
DINOSAURS These were a group of prehistoric reptiles that lived only on the land. They ranged in size from those of a modern day turkey up to those longer than three double-decker buses. In all, we can be certain there were at least 150 different types of dinosaur.
EARTH Our planet formed together with the Sun and the rest of the solar system some 4,500 million years ago. The Earth is an immensely hot planet wrapped in a thin, solid crust. There are three more layers called the mantle, the outer core and the inner core.
EARTH'S CORE Formed by the two deepest layers of the Earth. The outer core lies beneath the mantel. It is roughly 2000 km deep and hot enough for the rocks to be in a liquid form. The inner core makes up the centre of the Earth and has a thickness of about 1300 km. The temperature here may be up to 6000°C, but because of the weight of the material above, it is solid.
EARTHQUAKE When two plates of the Earth's crust push along side one another where they meet is known as a fault. Pressure builds up, and this can overcome the friction holding the plates firmly together. Suddenly the rocks move along the fault with a resulting earthquake. Depending on the strength of the movement, earth tremors may be unnoticed except by delicate equipment, or very violent causing much disaster. The ground can shake for many seconds and after shocks felt for hours afterwards.
ERA A major division of Earth's geological time. Only three eras cover the time span from the ceation of the Earth to the present day - Palaeozoic, Mesozoic and Cenozoic.
GONDWANALAND The southern grouping of continents which at the beginning of the Mesozoic Era made up the giant super-continent of Pangea.
JURASSIC PERIOD The second geological time period of the Mesozioc Era dating from about 205 to 135 million years ago. Flying reptiles appeared, as did the first birds. Dinosaurs were, of course, abundant across the land.
LAURASIA The northern groups of continents which together with Gondwanaland formed the giant continent of Pangea.
MANTLE This layer of our planet lies below the crust, it is about 2900 km thick, and is hot enough for most of the rock to be partly melted. Convection currents caused by heating from below mean the mantle material swirls about slowly and causes the plates (the crust) on its surface to move.
MESOZOIC ERA The age when the dinosaurs ruled the land. This era ran from about 225 to 65 million years ago, and was made of three geological time periods called Triassic, Jurassic and Cretaceous. During this span of 160 million years continents broke up, climates changed, reptiles took over the land and sea, and mammals made their first appearance. It Ended when a possible meteorite smashed into the Earth and wiped out the dinosaurs.
NATURAL SELECTION The main process of evolution where animals and plants that adapt best to the climate, finding food and escaping danger among others, end up by producing more young. Also called 'Survival of the Fittest'.
PANGEA The super-continent which was made when all the land of the world was joined at the beginning of the Mesozoic Era.
PERIOD A time forming a part of a geogogical era i.e. the Triassic, Jurassic and Cretaceous periods make up the Mesozoic era.
PLATES The Earth's crust is composed of seven large plates and at least eight smaller ones. Each one is moving extremely slowly according to currents set up in the mantle below (a process termed as 'Continental Drift'). Due to the fact that the surface must remain in equilibrium new land created in one area must result in destruction at another. So, four different plate boundaries are in existence - spreading ridges, subduction zones, collision zones, and transform faults.
STELLAR NURSERY An area in space where huge dust and gas clouds are condensing to make new stars with possible planetary systems like our own..
TRIASSIC PERIOD The first part of the Mesozoic Era starting approximately 245 million years ago. The beginning of 'the age of the dinosaurs'.All the land during this time had joined to form one great super-continent known as Pangea.
VOLCANO A mountain or hill which has an opening in the earth's crust through which material from the mantle is expelled, sometimes quite violently. They occur where there are weaknesses in the crust, mainly around plate boundaries.
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