New physics is learnt from extreme or fundamental things

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2 New physics is learnt from extreme or fundamental things

3 New physics is learnt from extreme or fundamental things The Universe is full of extremes and is about as fundamental as it gets!

4 New physics is learnt from extreme or fundamental things The Universe is full of extremes and is about as fundamental as it gets! Astrophysics/astronomy is about doing physics with the Universe as a laboratory

5 Progress through Observation

6 Telescopes and Technology Telescopes and instruments are core to Astronomy Advances in technology and astronomy tend to work sideby-side Traditional Astronomy The 10-metre diameter mirror of Keck 1

7 Observing Run

8 Observing Run

9 Observing Run

10 What can we Observe? With the right instruments can see lots of different things!

11 What can we Observe? With the right instruments can see lots of different things! Most observations are of apparent properties rather than absolute ones.

12 Called Photometry Also apparent measurement Modern cameras count photons! Brightness can tell us about: Distance (via standard candles ) Energy (if we know distance) Variability Brightness

13 Brightness Globular Cluster M15 All stars at the same distance

14 Brightness Globular Cluster M15 All stars at the same distance Difference in brightness due to different sizes

15 But what about colour? Cameras count photons, but do not tell us their colour (wavelength) Filters to the rescue! Compare the brightness through two different filters colour! Some of the Liverpool Telescope filters

16 Colours and Temperature

17 Old and New In general, the brightest young stars are blue, and the brightest old stars are red

18 Simple Chemistry Red: Hydrogen Green: Oxygen Also depends on temperature etc

19 Complex Chemistry All elements produce particular patterns of emission and absorption lines Details depend on lots of things including: Temperature Density Pressure Magnetic field Speed etc So, we use Spectroscopy

20 FRODOSpec

21 Redshifts/Blueshifts Can use Doppler Effect to measure the speed of an object Spectrum of stationary object Redshifted spectrum of object moving away

22 Example: Doppler Wobble Exoplanets Wobble of a star caused by the orbits of a planet around it!

23 Example: Doppler Wobble Exoplanets Wobble of a star caused by the orbits of a planet around it!

24 Example: Doppler Wobble Exoplanets Wobble of a star caused by the orbit of a planet around it!

25 Just the beginning Everything so far about visible light:

26 Just the beginning Everything so far about visible light: But this is a tiny part of the Electromagnetic Spectrum:

27 Problem: The Atmosphere X-ray UV Visible Infrared Radio Wavelength

28 Is it really a problem?

29 Visible Image (Hα filter) A quick look at the Sun

30 X-ray Image A quick look at the Sun

31 The Corona Corona Mass Ejections seen in far-uv by SOHO

32 The Corona End of two comets observations from SOHO

33 Galaxy Cygnus A

34 Example: UK Deep Survey Deep Optical Observation Deep X-Ray Observation

35 Driven by technology Subaru Telescope Part of UK Deep Survey Field

36 Driven by technology ROSAT Satellite Part of UK Deep Survey Field

37 Driven by technology Chandra Satellite Part of UK Deep Survey Field

38 Driven by technology Subaru Telescope Part of UK Deep Survey Field

39 Optical Light Learning Physics 3C465

40 X-rays Learning Physics 3C465

41 Radio Learning Physics 3C465

42 Learning Physics 3C465 Optical Light: Black Body. Made by stars, so nuclear fusion. About 1x10 12 stars (ie 1,000,000,000,000). Normal physics.

43 Learning Physics 3C465 X-rays: Also Black Body, but > 1,000,000 K. Very hot (but diffuse) gas. Gas stripped out of galaxies by tides! Tells us about age, gravity and types of atoms.

44 Learning Physics 3C465 Radio: Non-thermal. Huge jets of particles moving at ~speed of light. Massive energy source in the centre of a galaxy. Super-massive black hole!

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46 8m aperture Very large Fieldof-View Monitor the whole (visible) sky twice a week Expect ~1,000,000 new variable objects every night!

47 Liverpool Telescope 2

48 Next Generation of telescope 40m primary mirror Planned to start observing early 2020s Major questions: Are we alone? What were the very first objects in the universe? Massive technology/engineering/ computing/political task! ELT

49 ELT

50 Future of Radio: SKA Square Kilometre Array Collecting area: 1,000,000 m 2 Site: Australia and Southern Africa

51 SKA

52 Further Future: Mission to Mars? Several probes sent to Mars, but when will be actually go there? Perhaps as early as 2030

53 Beyond the EM-Spectrum EM-radiation only one way that information travels through the universe Astronomers now using other messengers : Cosmic Rays Neutrinos Gravitational Waves

54 H.E.S.S. Cosmic Rays CRs are very-high energy particles (plus some gamma-rays). Can be detected directly or (for the highest energies) via air showers. Tell us about the most extreme events in the universe.

55 Neutrinos Almost massless particles Very hard to stop but a very small fraction can be detected in large telescopes Many from the Sun, but also detected from extragalactic sources Super Kamiokande

56 Gravitational Waves Ripples in space caused by movement of dense objects Very, very small effect but might be detectable with large instruments Potentially very exciting!

57 Astronomy is an Observational science Telescopes let us see the universe in many new ways Technology drives everything The more we look, the more we see, and the more we see the more exciting it gets

58 Further information National Schools Observatory: ESERO: Me and NSO

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