radio astronomy for amateursradio astronomy for amateurs paul hyde baa radio astronomy group...

RADIO ASTRONOMY FOR AMATEURS

Paul HydeBAA Radio Astronomy Group([email protected])

Norfolk Amateur Radio Club2016 September 14

Po

wer

Flu

x D

en

sit

y (W

m-2

Hz

-1)

10-15

Broadcast signals

10-17

10-19

10-21

10-23

10-25

Supernova remnants

Radio galaxies

Pulsars

Communications Receiver

Courtesy Dr David Morgan

A million times weaker still!

10-13

Reference level

10,000 x sensitivity

Radio signals are weak

Background noise is high

To observe a source, we have to be able to distinguish it from the background noise, i.e. achieve a reasonable Signal to Noise Ratio

What can amateurs observe

1. Use INDIRECT observations

Look at the effects of an event, not the event itself

a) Sudden Ionospheric Disturbances (SIDs)

b) Meteor Scatter

2. Look at sources closer to home

a) Jupiter – Io emissions

b) Solar radio bursts

3. More advanced applications

a) Hydrogen Line reception

b) Interferometry

Sudden Ionospheric Disturbances

Very Low Frequency (VLF) radio signals (15 – 25 kHz) are guided between the conducting ground and the ionosphere

The ionosphere responds quickly to changes in solar X-ray and UV emissions associated with flares


Sunrise Sunset

Red trace 19.6 kHz Anthorn, CumbriaGreen trace 20.9 kHz St Assise, FranceBlue trace 22.1 kHz Skelton, Cumbria

Radio SkyPipe software


C2.3

C8.8M1.3

Radio SkyPipe software


VLF Receiving Systemwww.ukraa.com


Zotac Z-box mini pc

Antenna

(multicore cable with cores daisy-chained together)

VLF Receiving SystemMark Edwards, Coventry

Connected to MIC input of a PC


Spectrum Lab software

Approx 2 hours

X-class event observed by Mark EdwardsCoventry

www.qsl.net/dl4yhf/spectra1.html

Meteor Scatter

24-hour visibility – day or night, in cloud or sunshine, with moon or light pollution

NASA

GRAVES Space Surveillance Radar

High power radar system located near to Dijon, France

Transmit frequency 143.05 MHz

Four antenna arrays producing individual beams stepping across the sky

Meteor Scatter

Rapidly moving meteor 'head'

500 Hz change in frequency is equivalent to 1,000 m/s change in Line of Sight (LOS) velocity

Radio source is GRAVES Space Radar at 143 MHz

10 secs

Frequency =

LOS velocity

Meteor Scatter

Extended plasma trail lasting tens of seconds(time is proportional to mass)

Shows 'beam switching' at GRAVES transmitter

FUNcube Dongle Software Defined Radio

Developed to receive the FUNcube-1 satellite

Expected to sell about 50 units but has sold > 10,000

£150 including p&p

Can also be used to receive:

Weather satellites & meteorological balloons

Hydrogen Line

Jupiter emissions

Meteor Scatter

Encouraging participation

“How to …” article in June and July 2014 editions

Positive feedback from Sky at Night editorial team

Further article requested for later this year

Articles available for download from the BAA RAG website www.britastro.org/radio/

Still talking £200 for a complete installation

Meteor Scatter

Meteor Scatter

Interesting detail in the trail as it splits into different layers moving at different velocities (frequencies)

International Space Station

10

15

20

25

30

35

40

45 90 135 180 225

E

l

e

v

a

t

i

o

n

Azimuth

Moon position for EME

13-Jul

22-Jun

20-Jun

19-Jun

18-Jun

17-Jun

16-Jun

Moonbounce

Indicative of power of the GRAVES radar system

Position of Moon when moonbounce signals seen

Moonbounce signal

Spectrum Lab software

Freeware audio analysis software

Displays 'pings'

Automated save of .jpg images and .wav sound files

Logs time, duration, intensity, frequency

Data can be uploaded to a comparison site

Meteor Scatter

Meteor activity

Images courtesy Radio Meteor Observing Bulletin

December 2006 Geminids

What can amateurs observe

1. Use INDIRECT observations

Look at the effects of an event, not the event itself

a) Sudden Ionospheric Disturbances (SIDs)

b) Meteor Scatter

2. Look at sources closer to home

a) Jupiter – Io emissions

b) Solar radio bursts

3. More advanced applications

a) Hydrogen Line reception

b) Interferometry

L-Bursts

Jupiter Emissions

S-Bursts

L-Bursts

Jupiter Emissions

Jupiter Emissions

NASA's 'Radio Jove' antenna and kit receiver

Jupiter emissions can be picked up with an ordinarycommunications receiver at around 20 MHz

Solar radio bursts

Bursts stronger at lower frequencies

Typical receiver sensitivity

Solar radio bursts

Laptop with Terminal Emulator and FITS file reader

Outdoor antenna(3 ele wire Yagi)

R75 Receiver and PIC-based Controller

Solar radio bursts37.50

38.25

MHz

UTC0700 0900 1100 1300 1500

Narrowband terrestrial interferers

Broadband terrestrial interferers

?

Solar radio bursts

37.50

38.25

MHz

Space Weather Prediction Center report:

0942 0949 RSP 025-180 V/3 ?Start End Sweep-

frequency

Radio

Burst

Type V burst

Intensity = Major

Enlarged detail

Solar radio bursts

37.50

38.25

MHz

www.izmiran.ru/stp/lars/

Solar radio bursts

TYPE III TYPE V TYPE II

www.izmiran.ru/stp/lars/

Solar radio bursts

e-CALLISTO receiver from ETH Zürich

Scans 45 - 870 MHz using a cable-TV tuner

30 units deployed across professional observatories around the world

Courtesy ETH Zurich

Solar radio bursts

X2 flare received using e-CALLISTO by Whit Reeve, Anchorage, Alaska

Solar radio bursts

Images courtesy Christian Monstein

ETH Zurich

Advanced stuff ...

'Weak signal' work is possible for the serious amateur:

1. Total Power instruments

Use a single antenna to obtain direct measurements of source- Hydrogen Line at 1421 MHz- Broadband Black Body- Synchrotron radiation

Brian Coleman’s Redenham Observatory

http://myweb.tiscali.co.uk/g4nns/radast.html

Hydrogen Line

Charts courtesy of John McKay3 Peaks Observatory

Galactic Longitude 180°



Rest frequency = 1,420 MHz

www.3peaks.org.uk/

Hydrogen Line

David Morgan's Monmouth Observatory

Hydrogen Line Observing Group

Doppler Shift Intensity

www.dmradas.co.uk/http://myweb.tiscali.co.uk/g4nns/HLOG.html

Hydrogen Line

Peter East’s £200 H-LineTelescope

• 4 off 22-ele Yagis

• £15 Budget TV Dongle

http://y1pwe.co.uk/RAProgs/

index.html

Raspberry PiSingle Board Computer

Future opportunities

Consumer electronicsfront-ends

£15

£30

£20 £5

Raspberry PiSingle Board ComputerConsumer

electronicsfront-ends

… with software defining the instrument

Meteor scatter Hydrogen Line Jupiter Solar radio bursts

SID receiver

Future opportunities

InterferometryAdd signals from two widely spaced antennas- Much higher resolution than single antenna- Ability to distinguish between small sources

and background noise

30 metres

West arm East arm

www.dmradas.co.uk/

Interferometry

Virgo A = M87

Giant elliptical galaxy with a supermassive Black Hole at the core

Distance = 53.5 million light years

www.dmradas.co.uk/

Conclusions

There are applications which are relatively straight forward and suitable for non-radio experts

Man-made interference is an increasing problem – we need to find radio-quiet sites

The more dedicated amateur can observe 'deep-sky' radio objects: Hydrogen Line, Radio Galaxies, Supernova remnants

A possible way forward is collaboration between Astronomical Societies, Amateur Radio Clubs and software 'hackers'

Resources

TutorialsBasics of Radio AstronomyExcellent introduction to the concepts that lie at the heart of radio astronomy

Radio Astronomy TutorialsMore advanced tutorials from MIT Haystack observatory.

NJIT Course notes by Prof. Dale E. GaryAnother advanced series of lectures covering all aspects of radio astronomy

See www.britastro.org/radio/

ByJeff Lashley

By John Fielding

Burlington HousePiccadillyLondon

W1J 0DU

(+44) 207 734 4145 [email protected]

Registered Charity No. 210769

British Astronomical AssociationRadio Astronomy Group

radio astronomy for amateursradio astronomy for amateurs paul hyde baa radio astronomy group...

Documents