P7.5

Question 1

1. Where are major optical and infrared astronomical observatories on Earth mostly situated?

Answer 1

-in Chile, Hawaii, Australia and the Canary Islands

Question 2

2. What are factors that influence the choice of site for major astronomical observatories?

Answer 2

1- high elevation
=thinner atmosphere so less effects of atmosphere
2- frequent cloudless nights
=more time for observing
3- low atmospheric pollution and dry air
=less light refraction from water molecules
4- sufficient distance from built up areas that cause light pollution
=light doesn’t interfere with observations

Question 3

3. What types of telescopes can astronomers work with?

Answer 3

• local

- remote

Question 4

3. What is a local telescope?

Answer 4

-nearby, can easily get to

Question 5

3. What is a remote telescope?

Answer 5

-far away, hard to get to

Question 6

4. What are the advantages of computer control of telescopes including:

Answer 6

1- being able to work remotely
=caves time and money
-e.g. space telescopes
2- continuous tracking of objects
=network of telescopes so can use them when it is night in that place
3- more precise positioning of the telescope
+ when doing a survey which needs lots of repositioning
4- computer recording and processing of data collected

Question 7

5. What are the main advantages and disadvantages of using telescopes outside the Earth’s atmosphere?

Answer 7

1- avoids absorption and refraction effects of atmosphere
=light not absorbed by dist or refracted by water
2- can use parts of electromagnetic spectrum that the atmosphere absorbs
3- cost of setting up, maintaining and repairing
=have to send men up
4- uncertainties of space programme
=funding can be cut for health services, natural disasters, defence etc
=harmful as often linked programmes

Question 8

6. What are the reasons for international collaboration in astronomical research?

Answer 8

-sharing cost, resources and expertise

Question 9

7. What are two examples showing how international cooperation is essential for progress in astronomy?

Answer 9

International space station
=led by US
=help of 15 countries including European space agency
European extremely large telescope
=based in Chile
=help of European astronomers

Question 10

8. What non-astronomical factors are important considerations in planning, building, operating, and closing down an observatory?

Answer 10

1- cost
2- environmental impact near the observatory
=disturbs wildlife
3- social impact near the observatory
=provides jobs
4- working conditions for employees.
=need accommodation and facilities and transport