1 13 Radio Astronomy Source Verification

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Radio Astronomy Source Verification

AN OBSERVATION AID DOCUMENT

Actual Radio Astronomy Observations for use in identifying and validatingyour observations.

This source information has been collected from various sources in the amateur and professionalradio astronomy field.

No equipment endorsement will be made in this document, only the source identification,equipment used, frequency and observer. Submissions are invited and may be made to this

document, by sending the observation and related information describing the event to:[email protected] [email protected]

This document is made available to alland requires no password or specific affiliation with anyorganization. However, it is highly recommended that any user referencing the materialwithin, quote the source and contributor of each observation.

Contributors to this document:

Rodney Howe

Hans Michlamyr

Carl Lyster Jonathan Pettingale

Dr. John Bernard

James Van Prooyen

Jeff Lichtman

http://www.thrushobservatory.org/radio.htm

Referenced Information:

For Jupiter, RadioSky http://www.radiosky.com/rjcentral.html


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Table of Contents

Contents Page

SOLAR RADIO OBSERVATIONS................................................................................................................ 3

VLF Microwave ............................................................................................................................................ 3

JUPITER RADIO OBSERVATIONS ............................................................................................................. 5GALACTIC RADIO OBSERVATIONS (Drift Scan) .................................................................................... 6

GALACTIC RADIO OBSERVATIONS (Interferometry).............................................................................. 8SPECIFIC RADIO SOURCES (Pulsars) ...................................................................................................... 10

SPECIFIC RADIO SOURCES (Quasars) ..................................................................................................... 12

CALIBRATION TECHNIQUES................................................................................................................... 13


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SOLAR RADIO OBSERVATIONS

VLF Microwave

RAS 40 KHz Receiver

Carl Lyster


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Jonathan Pettingale, UK

RAS 1.4 GHzUltaCyber8 Foot Antenna


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JUPITER RADIO OBSERVATIONShttp://www.thrushobservatory.org/radio.htm

S Burst

L Burst


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GALACTIC RADIO OBSERVATIONS(Drift Scan)

Pisgah Astronomical Research Institute - 1.4 GHz (RAS SpectraCyber) 85 Foot Antenna &PARI Software


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GALACTIC RADIO OBSERVATIONS(Drift Scan) Continued

Rodney Howe (DSES) - 1.4 GHz (RAS SpectraCyber)


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Dr. John Bernard - SpectraCyber with Methanol Converter- 12 Foot Antenna usingDr. Bernard - Software Creator / RAS Software

GALACTIC RADIO OBSERVATIONS(Interferometry)

Hans Michlamayr (Australia) Cent. A and Cyg. A @ 1410 MHz, 12 Foot StretchedParabolas


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GALACTIC RADIO OBSERVATIONS(Interferometry) Continued

Hans Michlamayr (Australia) Orion A @ 1410 MHz, 12 Foot Stretched Parabolas


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SPECIFIC RADIO SOURCES(Pulsars)

Jim Van Prooyen - Pulsar B003-1-07 - 406.7 MHz (RAS System) 10 Foot AntennaPulsar Software developed by Jim Van Prooyen

Jim Van Prooyen - Pulsar B003-1-07 - 406.7 MHz (RAS System) 10 Foot AntennaPulsar Software developed by Jim Van Prooyen

Pulsar B0031-07/J.Van Prooyen/GRRO

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Time, 0.055 seconds per tick

SignalStrength

Pulsar B0950+08/J.Van Prooyen/GRRO

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SignalStrength


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Jim Van Prooyen - Pulsar B1133+16 - 406.7 MHz (RAS System) 10 Foot AntennaPulsar Software developed by Jim Van Prooyen

Jim Van Prooyen - Pulsar B1919+21 - 406.7 MHz (RAS System) 10 Foot AntennaPulsar Software developed by Jim Van Prooyen


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0 50 100 150 200 250 300 350 400

Time 0.055 seconds per tick

SignalStrength


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SignalStrength


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SPECIFIC RADIO SOURCES(Quasars)

Rodney Howe (DSES) - 3C033 - 1.4 GHz (RAS SpectraCyber)


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CALIBRATION TECHNIQUES

Radio Astronomy SuppliesAPPLICATION NOTE 5

NOISE TEMPERATURE, FIGURE and FACTOR CALCULATIONS

Basic formulae are:Noise Temperature (T) = 290 * (10^(Noise Figure/10)-1) K

Noise Figure (NF) = 10 * log (Noise factor) dB

Notes:Log must be to base 10. When using calculators and spreadsheets make sure that base 10 isselected. As a test, 10 * log(2) should give an answer of +3 dB. Noise temperature is measured inunits called Kelvin (K) and these are like Celsius (C) temperature degrees but start at zero forabsolute zero temperature so:

0 K = -273 deg C273 K = 0 deg C (ice melts)

290 K = 17 deg C (ambient temperature of a cable, for example)

Table to convert Noise Figure (NF) to Noise Temperature (T). This is useful for working out LNA orLNB noise temperatures from advertised Noise Figures.

Procedure for adding up noise temperatures for antenna, waveguide, LNA, cable andreceiver in series:

Notes: T system is referred to the input of the LNA.You need to convert gains in dB to numbers. Number = 10 ^(dB/10)

(continued)


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T system = Noise contribution from antenna = Tantenna * waveguide gain+ noise contribution of the waveguide = 290 * (1-waveguide gain)+ noise contribution of the LNA = the LNA noise temp+ noise contribution of the cable = 290 / LNA gain+ noise contribution of the receiver= receiver noise temp / (LNA gain * cable gain)

Example: Antenna noise temperature = 35 K (mainly ground pick up noise)Waveguide feeder gain = -0.25 dB (0.944), temperature = 290KLNA gain = 50 dB (100000), noise temperature = 75 KCable gain = -20 dB (0.001), temperature = 290KReceiver noise temperature = 2000 KTsystem = 35 * 0.944 = 33 Noise contribution of the antenna+ 290 ( 1 - 0.944) = 16 Noise contribution of the waveguide+ 75 Noise contribution of the LNA+ 290 /100000 = 0.003 Noise contribution of the cable+ 2000/(100000 * 0.001) = 2 Noise contribution of the receiver

= 126 K

Note that LNA noise temperature, the antenna noise temperature and waveguide loss arethe main factors.

With permission from Eric JohnstonEmail Eric Johnston

[email protected]

Additional Calibration Information on the following page.


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