1. "Celebrating Yuri’s Night"
Niall Smith

2. Specifically for Teachers
Nature of Science 1: “Appreciate how scientists work and how scientific ideas are modified over time“
Nature of Science 10: “Appreciate  the role of science in society; and its personal, social and global importance; and how society influences scientific research”
Earth and Space 8: “Examine some of the current hazards and benefits of space exploration and discuss the future role and implications of space exploration in society”

3. Sputnik

4. Yuri Gagarin -
12 April 1961

5. Observe and deduce

6. This is also true of asteroids
Prevalence of Impacts
Moon
Mercury
Moon and Mercury both show significant evidence of crater impact after they had become geologically inactive
This is also true of asteroids
This suggests that large bombardments occurred at some time in the PAST (since we don’t see them happening much today)
(Moon and Mercury shown different scales)
Mercury closeup
Asteroid Phoebe closeup
Moon closeup
Credit: NASA

7. Theories of Lunar Formation
Moon being a captured object
Highly unlikely
Spun-off by a rapidly rotating Earth
Early Earth did not spin fast enough
These theories don’t work
As a result of a collision with a Mars-sized planet called THEIA
“Giant Impact Theory”

8. Collisions in recent times

11. Threats from Space

12. Earth crossing NEOs
Asteroids
Earth crossing asteroids

13. Oumuamua – from beyond the Solar System

14. Earth Sterilizing Impacts are Possible
Inevitable

16. Not all collisions are bad

17. Early earth – 4.5 billion years ago – was too hot to retain water
So where did it come from?
HADEAN EARTH

18. Asteroids may be responsible for much of Earth’s water – not comets!!

19. What is space junk? Orbital bits that do nothing useful:
spent rockets;
fragments splayed by collisions and degradation;
old satellites no one cares about anymore
In total, they amount to millions of pieces of debris
And it's about to get worse: Thousands and thousands of satellites are set to launch to low-Earth orbit before 2025.

20. The key issue in a collision is energy
This is determined by the Kinetic Energy in the interaction: K.E. = ½ . M. V2
(where M = mass of the debris and V = velocity between the debris and the target)
Collision velocities can be as high as 8 km/s
18,000 mph
4 times faster than a bullet

21. Radar and optical track pieces in low-earth-orbit as small as 5-10cm
For higher orbits its 30cm – 1m
Debris of <1mm can be inferred from returned satellites and dedicated instruments on others
Estimates >170 million pieces

22. ISS Impact Chip
Quadruple glazing!

23. Sentinel 1A impact damage

24. Occasionally pieces of debris reach the ground

25. Some Impacts are Intentional … 2007
Feng Yun-1C Weather Satellite
3400 tracked fragments

26. Others are accidental … 10th Feb 2009
Iridium 33
2300 fragments
Kosmos 2251

27. And Low-Earth-Orbit is increasingly tempting …
Cubesats and Space 4.0 or New Space

28. Why is Low-Earth-Orbit of such interest?
Requires the lowest amount of energy for satellite placement.
It provides high bandwidth and low communication latency. Satellites and space stations in LEO are more accessible for crew and servicing.
Satellite needs less powerful amplifiers for successful transmission - LEO is used for many communication applications, such as the Iridium phone system.
“Disadvantages”
Satellites in LEO have a small momentary field of view, only able to observe and communicate with a fraction of the Earth at a time, meaning a network (or "constellation") of satellites is required to in order to provide continuous coverage. Satellites in lower regions of LEO also suffer from fast orbital decay, requiring either periodic reboosting to maintain a stable orbit, or launching replacement satellites when old ones re-enter.

29. The “cubesat” is the new standard form LEO satellites
“Sprites”
Satellites are getting smaller, but impressively powerful, as technology advances
“Cubesats”

30. New Space is Why? Rockets built by private companies
Satellites built by private companies, universities and (increasingly) schools – with satellites becoming smaller and lighter
Why?
To provide information to people who live on the Earth that can’t be obtained in other ways
THE USES FOR THESE SMALL SATELLITES IS LIMITED ONLY BY YOUR IMAGINATION!

31. New countries such as India are also getting involved ..
2017
31 payloads delivered by this Indian rocket

32. … or New Zealand … New Zealand are interested in building rockets for:
Specific Tasks
Specific Orbits
New Zealand

33. Some big targets for New Space
Connecting the 3.8 billion people not currently connected to the web
(Even rural broadband in Ireland)
Autonomous vehicles
Earth observation
Almost any application you can think of!
Space Tourism
Space Exploration
The Moon Village
Mars

35. Huge interest in Constellations of Satellites
The company ONEWeb ultimately plan to launch 2417 satellites

36. People are also interested in ….

37. Restore-L NASA Mission
People are also interested in ….
ESA e.Deorbit mission
Restore-L NASA Mission

38. Or ….
Ecologically friendly spacecraft

39. But Space 4.0 is here to stay

40. And there are always people with new ideas …

41. THANKYOU