2.5 Space programme  (Page 3/3)

So many nations - So many missions!

Why not coordinate all the efforts?

• The reason : for having so many space probes is that the more efforts there are, the greater the degree of success. Many space missions do not succeed owing to problems with launching, orbiting or landing. NASA will attempt 3 landings on Mars within a period of 15 months.
• After the explosion of the shuttle Columbia, questions were again asked about the value of space research. The conclusion, in the words of Bill Readdy, a NASA administrator at the time of the Columbia tragedy, was: “Pushing the frontiers of space is dangerous”, and in those of President George Bush: “Our journey into space will go on…”

DEEP SPACE

• This is where stars are born and where so-called black holes occur.

Life cycle of a STAR

• A star starts as a gas cloud.
• This gas cloud heats up as a result of the force of gravity.
• A nuclear reaction starts and a star is born.
• As nuclei are converted, the star becomes hotter.
• The nucleus becomes increasingly hotter and the surface cools down.
• The star expands and is now called a red giant.
• Layers are discarded, the inner core collapses and a white dwarf is formed.
• This will happen to our sun in about 5 billion years’ time!
• When a star dies, it explodes in a supernova - this is as bright as a million suns!
• The section that remains can be either a neutron star or a pulsar or a black hole.
• A black hole is formed when matter is compressed until it is so dense that not even light can escape the pull of its gravity.

Colours of STARS

• The whiter the star, the hotter it is and the brighter it shines.
• The redder it is, the cooler and fainter it is.
• Red stars that are bright are therefore closer and white stars that are faint are very far away.

Bright STARS in SPACE

• If you are in the Southern Hemisphere and look south (i.e. the sun has set to your right), you will see two bright stars. They are α-Cen, also known as Alpha Centauri, and β-cen or Beta Centauri. Together they are called the Pointers, as they point to the Southern Cross.
• Excluding the sun, α-Cen is our nearest star.
• Let’s see whether it’s possible to send a shuttle to α-Cen.

Activity: deep space

1. Why should man have space programmes and launch space probes?

2. Compile a flow diagram of the phases of a star’s life cycle.

3. State two ways in which satellites currently play a role in your life.

4. Explain the following astronomical terms:

5. State the benefit of the ISS for mankind.

Assessment of QUESTIONS ON DEEP SPACE:

a) Do you understand the terms?

b) Could you do the flow diagram correctly?

c) Do you understand the reasons for space programmes?

[LO 2.1; LO 2.2; LO 3.1]

Assessment

LO 2: Constructing Science Knowledge:

The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

This is evident when the learner:

• recalls meaningful information;
• categorises information.

LO 3: Science, Society and the Environment

The learner will be able to demonstrate an understanding of the interrelationships between science and technology, society and the environment.

This is evident when the learner:

3.1 understands science as a human endeavour;

3.2 understands sustainable use of the earth’s resources.

Memorandum

Space programmes

ACTIVITY: QUESTIONS

1. to gain more knowledge of possibilities beyond our own planet

2. gas cloudheatingforcesnuclear reactionexpansionlayers cast off inner core collapses explosion/supernovaneutron or “black hole” remains

3. telecommunication, television transmissions, weather forecasts

4.