1. I bet you didn’t know… Planetary Hide and Seek
Teacher Guide
Curriculum Areas
Space
Ages
4-11 years
© NASA

2. Copyright
The materials included in these resources are ©Primary Science Teaching Trust 2019, but may be freely reproduced by teachers in schools for educational purposes, subject to the source being credited.
Materials may not be used for promotional or commercial purposes without the express permission of the PSTT. On no account may copies be offered for sale.
Disclaimer
Primary Science Teaching Trust (PSTT) is not liable for the actions or activities of any reader or anyone else who uses the information in this document or the associated classroom materials. PSTT assumes no liability with regard to injuries or damage to property that may occur as a result of using the information contained in these plans.
PSTT recommends that a full risk assessment is carried out before undertaking in the classroom any of the practical investigations contained in the power point.
Safety note
PSTT advises teachers to refer to either CLEAPSS website or SSERC website for up to date health and safety information when planning practical activities for children.
This power point is intended to be a guide for teachers for their reference although they may wish to show certain slides in the classroom.
We would welcome any feedback on these materials.

3. Did you realise that both scientists are female?
Who are the scientists?
The Curiously Warped Mean Plane of the Kuiper Belt
Kathryn Volk and Renu Malhotra
Lunar and Planetary Laboratory
The University of Arizona
USA
Did you realise that both scientists are female?
Professor Malhotra has an asteroid named after her and has had a very distinguished career as an astronomer.

4. What did the scientists know?
Eight planets have been identified in our Solar System.
Pluto which was once defined as the 9th planet is now defined as a dwarf planet.
Beyond Pluto is a ring of icy objects such as comets called the Kuiper Belt.

5. What did the scientists do?
Scientists used telescopes to study the orbits of rocks in the Kuiper Belt.
Some Kuiper Belt objects (KBOs) have orbits that are tilted compared with what is normally seen.
To try to explain this, scientists have suggested that a planet roughly the size of Mars is present about 60 AU from the Sun.
© NASA
Why might AU (the distance between the Earth and the Sun) be a good unit of measure to use for astronomical studies?

6. Why is the planet hidden?
What did the scientists find out?
Scientists think that a 9th planet is hidden in the Kuiper Belt.
There may even be more than one hidden planet.
Why is the planet hidden?
© NASA

7. Quick activity
Can you find an object without using your eyes?
Resources
Ticking clock or timer

8. Longer investigation
How might we locate an object that we cannot see?
Use your senses to find what is hidden or hide something for others to find.
Resources
Ticking clocks, timers, clockwork toys, vibrating objects,
smelly pots (margarine pots with punctured lids containing lavender oil, blue cheese, garlic etc.),
magnets & magnetic objects

9. How can you find objects that you cannot see?
What did you find out?
How can you find objects that you cannot see?
How can scientists find objects that they cannot see?
The Hubble Telescope - the only telescope designed to be maintained in space by astronauts.
In 2021 a new telescope will be able to ‘see’ 20 times the KBOs currently seen. We will have to wait and see!

10. Questions for further learning
Can you name and order the planets in our Solar System?
(art/drama) Children could draw/make plasticine models/act out the movement of the planets around the sun.
Can you describe the relative sizes of the planets and the distances between them?
Children could make model planets scale measurements on the school field or smaller scale using modelling clay.
What is a telescope and how does it work?
Children could investigate magnification and how lenses work by putting a couple of drops of water on a newspaper – look at the effect on the small letters.
What happens when you jump? Why don’t you move upwards into the sky? Look at a globe – what happens if you live in Australia? With older children: look at films of astronauts on the Moon in space, why is the astronaut’s walk different to normal?

11. Maths links
Area of learning
Activity
Measurements & scales
Make scale models of the planets using paper or modelling clay, mark the relative distances between the planets using strips of paper or outside on the playground.
Geometry
Drawing circles using compasses

12. Writing links
Area of learning
Activity
Narrative
Describe life on a hidden planet, or the journey of a rocket travelling there what do you see on the way?)
Newspaper report
Write a report announcing the discovery of a new planet.

13. For more information on the Primary Science Teaching Trust and access to a large selection of PSTT resources, visit our website:
pstt.org.uk
/primaryscienceteachingtrust @pstt_whyhow
To help you find high quality resources to support your primary science teaching quickly and easily, we provide links to excellent resources for teachers, children and families on our Wow Science website :
wowscience.co.uk
and we regularly provide further suggestions on how to use these in the classroom through social media platforms:
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