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The Radio Sky

Chris Salter NAIC/Arecibo Observatory. The Radio Sky. I find a very steady hiss type static of unknown origin Whose direction of arrival goes almost around the Compass in 24 hours Karl Jansky -- 1932.

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The Radio Sky

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  1. Chris Salter NAIC/Arecibo Observatory The Radio Sky

  2. I find a very steadyhiss type static of unknown origin Whose direction of arrival goes almost around the Compass in 24 hours Karl Jansky -- 1932 “Suppose that our eyes responded to radio waves, rather than light, how different would the Night Sky appear?”

  3. Arecibo 305-m telescope (Puerto Rico)‏ GBT 100-m telescope (WV, USA)‏ Angular Resolution = /Diameter Effelsberg 100-m telescope (FRG)‏ IRAM 30-m mm-wave telescope (Spain)‏ Ooty Radio Telescope 530  30 m (India)‏ Our Radio Eyes

  4. Emission Mechanisms Thermalemission is unpolarized. a) Solid body; e.g. planet, you, me. b) Free-free emission from a hot ionized gas. c) Dust particles. d) Thermal spectral line emission. Non-thermal emission is generally polarized. a) Synchrotron Emission due to helical trajectories of ultra-relativistic electrons crossing interstellar magnetic fields. b) Maser-like line emission, e.g. OH, H2O, CH3OH and SiO. Water maser line Recombination Lines near 5 GHz

  5. The Whole Radio Sky (408 MHz – λ73 cm)‏ Cen-A North Polar Spur Cyg-X; (the local Main St.)‏ Cas-A SMC & LMC Galactic Center Synchrotron Emission

  6. Cosmic Micwave Background (WMAP; 90 GHz – λ3 mm)‏

  7. The Celestial Neutral Hydrogen (HI) Emission Continuum HI

  8. The Radio Solar System As seenby a “Passive” Radio Astronomer Moon -- (IRAM 30-m telescope; 230 GHz)‏ Saturn -- VLA Jupiter -- VLA

  9. Jupiter (Continuum spectrum, including decametric bursts)‏ 2.3 GHz (13 cm)‏ 1.4 GHz (22 cm)‏

  10. True Radio Stars Radio Light Curve X-ray Binary SS433 X-Ray Image Radio Image (Artist’s Impression)‏

  11. Supernova Remnants Cas A – about 1680 AD Crab Nebula – 1054 AD Supernova 1987A (Optical)‏ W 50 (AD 1572)‏

  12. Pulsars PSR 0329+54 About 1600 pulsars are currently known. Pulsar periodicities are between 0.0014 and 8.5 sec. All pulsars are slowing down. Discovery of Pulsars (1967)‏ The Double Pulsars (Artist’s Impression)‏

  13. Orion Nebula: Optical HII Regions – The Youngest Stars rotation When a molecule changes its rotation, vibration or bending state to one of lower energy, it radiates a photon. If the change of energy is very small, the photon is a radio photon. Radio Continuum Mm-wave Line Spectrum Free-free emission

  14. Spiral Galaxies M31 -- Optical M31 -- HI I M31 -- Radio Continuum

  15. Elliptical Galaxies M 87 -- Optical Centaurus A (Optical)‏ Cygnus A -- (Radio; FR II)‏ Centaurus A (High-resolution Radio; FR I)‏

  16. Radio Source Image Gallery 3C31 (Source in galaxy group)‏ NGC 1265 (Narrow-angled tail cluster galaxy)‏ 3C175 (Double-lobed quasar)‏ Fornax A (Nearby radio galaxy)‏ J0204+1514 (Compact Quasar)‏ 3C296 (Double-jet radio galaxy)‏

  17. The Canonical Model of AGNs MODEL Optical Radio

  18. Superluminal Motion & Gravitational Lensing 4C 05.51 CLASS B1359+154

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