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What is Radio Astronomy?. MIT Haystack Observatory This material was developed under a grant from the National Science Foundation. The Electromagnetic Spectrum. Spans a range of wavelengths Visible is just a narrow range Radiowaves span a large range - from under 1mm to several meters.
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What is Radio Astronomy? MIT Haystack Observatory This material was developed under a grant from the National Science Foundation
The Electromagnetic Spectrum • Spans a range of wavelengths • Visible is just a narrow range • Radiowaves span a large range - from under 1mm to several meters
Sources of Radio emission • Solar System - sun, planets • Milky way - star forming regions, old stars, supernova remnants • Extragalactic - quasars, radio jets • Molecules
Orion Nebula: Stars are born…RADIO INFRARED OPTICAL XRAY
Crab Nebula: a star that died in 1054RADIO OPTICAL XRAY
What are molecules good for? • Detections - newest one - “glycoaldehyde” (sugar) • Probes - measure temperature, density, chemistry • Kinematics - velocities - doppler effect
HC3N as a density probe in the Taurus Molecular Cloud (TMC-1)
Interferometry Getting better “resolution”
NRAO/AUI Compare the radio image on the right, made with the Haystack 37-m single dish telescope at a frequency of 43 GHz with the radio image above made with the 27-element Very Large Array.
Magnetic Fields in Active Galactic Nuclei • The Blazar 1055+018 • Active Galactic Nuclei • 15 billion light years distant • AGN are 40 times more luminous and 10,000 times larger than the brightest “normal” galaxies • Displays a colossal jet of relativistic plasma • Powered by a supermassive, rotating black hole