1. DR ELIZABETH ALEXANDER: FIRST FEMALE RADIO ASTRONOMER?
Wayne Orchiston
Australia Telescope National Facility, and
Anglo-Australian Observatory, PO Box 76, Epping, NSW 2121, Australia.

2. 1. INTRODUCTION Jansky & Reber WWII radar Solar Detections Hey (UK)
Reber; Southworth (US)
Alexander (NZ)
Germans (Denmark)
Slee (Australia)

3. 2. FRANCES ELIZABETH SOMERVILLE ALEXANDER (neé CALDWELL)
1908 b. December 13 (Merton, Surrey, UK)
1909 India (Patna Science College)
1918 England
1931 Cambridge (Geology; Harkness Prize)
1934 Cambridge Ph.D. (Aymestry Limestone)
1935 Married Dr N.S. Alexander
1936 Singapore (Navy: radio direction-finding)
1942 New Zealand (+ William, Mary & Bernice)
1946 England
1947 Singapore (Raffles College > U Malaya)
1952 Nigeria (University College, Ibadan )
1958 d. October 23 (Ibadan, Nigeria)

4. ‘Norfolk Island Effect’
3. WARTIME IN N.Z.
RDL (Op. Res. Section)
Radar developments
Whales & seagulls
‘Canterbury Project’
‘Norfolk Island Effect’

5. 4. THE ‘NORFOLK ISLAND EFFECT’
RNZAF 200 MHz COL radar units N.Z. + Norfolk Is

6. Norfolk Island: March 27 – April 01 Large increases in ‘radio noise’ recorded near sunrise & sunset “Rotation of the aerial showed noise fluctuations corresponding fairly closely to the radiation diagram of the aerial. At its maximum the noise reached saturation on the azimuth of the sun …” (Alexander, 1945a: 1). Elizabeth Alexander assigned to investigate the “Norfolk Island Effect”

7. Monitoring: 1945 April 10 – 23 Northern NZ + Norfolk Is#5
1 = Norfolk Island
2 = North Cape
3 = Whangaroa
4 = Maunganui Bluff
5 = Piha

8. At Whangaroa microammeter inserted between
the receiver output and diode limiter = immediate
results.
Combined observations enough to convince
Alexander that
“… the Norfolk Island effect was significant
and was connected with radiation from the
sun …”

9. Intense 200 MHz solar emission centred on October 5:
1945 July-December: Air Force, Army & Navy Radars N.Z. + Norfolk Island
Intense 200 MHz solar emission centred on October 5:
“… violent surges of noise were observed at regular intervals. These surges were of momentary duration and sent the noise meter needle hard over.” (Alexander, 1945b).
At Piha (#5) Yagi also tracked Sun; gain < radar
“Noise signals from the direction of the sun were observed. The signals fluctuated rapidly but did not completely disappear until sunset.” (ibid.).

10. Overall results, 1945

11. End 1945/early 1946 radar stations & RDL closed:
E.A. to England + Singapore
Publication (new N.Z. journal): “The Sun’s radio energy.” Radio and Electronics, 1(1): (1946).
1945 March 28 ‘noise’ at Norfolk Is. not previously observed
Christened ‘Norfolk Island Effect’
1945 March-December two periods of intense sunspot
activity & “… these coincided with periods of intense solar
“noise”.”
Reports submitted to UK & Australia
Detections by others noted
Solar emission at 200 MHz non-thermal in origin, but “To
deduce solar temperatures of millions of degrees from this
radiation, as has been suggested … is absurd.”
“It is not in the least surprising that the Sun should emit
radio waves.”
More observations/analysis required (role of amateurs).

12. 5. THE SEQUEL Canterbury Project I. Thomsen (Nature paper)
A. Maxwell (M.Sc. Thesis)
R.F. Joyce

13. 6. CONCLUDING REMARKS Fortuitous: “Right place; right time!”
Anomalies: female, family, age, education
First female ‘radio astronomer’?
NZ sequel
Acknowledgements: Mary Harris, Bernice Jones, Bill Alexander, Gordon Burns, National Archives of New Zealand, E.R. Collins, Woody Sullivan.