Abstract
The career and scientific contribution to the development of radio astronomy by Bernard Yarnton Mills (1920–2011) is the focus of this chapter. Mills’s major achievements are described, including the invention of the Mills Cross radio telescope and his investigations into the nature of the discrete radio sources and their significance in cosmology.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
The swept-lobe interferometer was a Michelson interferometer (see Appendix A) with a response pattern that could be moved back and forth over the sun at a rate of 25 times a second. With the sea-cliff interferometer, the motion of the response pattern was limited to the slow rate governed by the rotation of the earth (scan duration of the sun about 2 min of time).
- 2.
The sea-cliff interferometer (see Appendix A) had first been used by McCready, Pawsey and Payne-Scott (1947) to investigate the source of solar radio emission. This was in fact the first use of interferometry in radio astronomy. Bolton and his team at Dover Heights went on to use the sea-cliff interferometer for the pioneering work in investigating the cosmic radio sources, and this resulted in the first three optical identifications of discrete radio sources, two extragalactic and one the Crab Nebula, the remnant of the supernova of 1054 (Bolton, Stanley, & Slee, 1949).
- 3.
Unsourced quotations are from Bernie Mills's autobiographical notes, held by the University of Sydney Archives.
- 4.
The first identifications of radio sources with optical objects required an accuracy of about 1 arcmin.
- 5.
For a full discussion of the identification of Cygnus A, see Sullivan, W. T. 2009. Cosmic noise: a history of early radio astronomy, Cambridge, Cambridge University Press pg 335.
- 6.
A technique to move the response pattern of the interferometer back and forth over a limited region of the sky; with this scheme, the long-term instrumental instabilities could be partly eliminated.
- 7.
In 1946, Robert Dicke of Princeton University developed an eponymous switching system for the detection of weak radio astronomy sources at microwave frequencies.
- 8.
The increased bandwidth leads to an increased sensitivity.
- 9.
The extended sources were observed to be larger than 1° on the sky, while the compact sources were smaller than 1°.
- 10.
The radio link was used to transmit (1) the signals back to the central receiver and (2) the control signals from the home station to the distant aerial.
- 11.
The reduction in side-lobe level was due to the filled geometry of both arms of the cross.
- 12.
See Appendix A.
- 13.
The mathematical operation to apply to the observational data in order to produce an image of the radio sky
- 14.
Fred Hoyle (1915–2001), prominent UK astrophysicist and cosmologist, primarily known for the theory of stellar nucleosynthesis. One of the founders of the Steady State theory of the universe along with Hermann Bondi and Thomas Gold. The Steady State theory is an alternative to the Big Bang model of the evolution of the universe. In the Steady State theory, the density of matter in the expanding universe remains unchanged due to a continuous creation of matter. The modern Big Bang theory is one in which the universe has a finite age and has evolved over time through cooling, expansion, and the formation of structures through gravitational collapse. The Big Bang is the accepted model of the universe in the twenty-first century.
- 15.
For a uniform distribution of sources in the universe as predicted in a Steady State universe, the slope was predicted to be −1.5; for an evolving universe (Big Bang), the slope was predicted to be somewhat more negative due to the changing properties of the sources over the lifetime of the universe (higher density of radio sources when the universe was younger).
- 16.
As an interesting aside, Bowen would later recreate the event of driving in the first peg at the Parkes site at another location some distance to the south of the telescope, effectively editing Mills and Christiansen out of his own history (see Fig. 3.18). In 1971, Frank Kerr told W.T. Sullivan about the staged event: “… Taffy Bowen went up to the site… with McCready and he got McCready to take a picture of him driving the post in. And that picture has been published in various propaganda journals”. In addition, Paul Jelbart, a nearby neighbour who lived on an adjacent property at Parkes, witnessed the recreation in September 1961, only a month before the official opening. The site of the recreation is some 200 m south of the 64 m telescope (John Sarkissian, private communication).
- 17.
Radio sources with previously determined accurate positions on the sky, usually associated with known radio galaxies or quasars. Often these sources had well determined flux densities.
References
Baade, W., & Minkowski, R. (1954). Identification of the radio sources in Cassiopeia, Cygnus A, and Puppis A. Astrophysical Journal, 119, 206–214.
Bailes, M., Jameson, A., Flynn, C. M. L., Bateman, T., Barr, E. D., Bhandari, S., Caleb, M., Campbell-Wilson, D., Farah, W., Gaensler, B., Green, A. J., Hunstead, R. W., Jankowski, F., Keane, E., Krishnan, V., Murphy, T., Parthasarathy, A., O’Neill, M., Ravi, V., Rosado, P., & Temby, D. (2017). The UTMOST: A hybrid digital signal processor transforms the Molonglo Observatory Synthesis Telescope. Publications of the Astronomical Society of Australia (in-press).
Bock, D. C., Large, M. I., & Sadler, E. M. (1999). SUMSS: A wide-field radio imaging survey of the southern sky. I. Science goals, survey design, and instrumentation. Astronomical Journal, 117, 1578–1593.
Bolton, J. G., Stanley, G. J., & Slee, O. B. (1949). Positions of three discrete sources of Galactic radio-frequency radiation. Nature, 164, 101–102.
Bowen, E. G. (1981). History of Australian astronomy – The pre-history of the Parkes 64-Metre Telescope. Proceedings of the Astronomical Society of Australia, 4, 267–273.
Bowen, E. G., Pulley, O. O., & Gooden, J. S. (1946). Application of pulse technique to the acceleration of elementary particles. Nature, 157, 840.
Christiansen, W. N., Yabsley, D. E., & Mills, B. Y. (1949a). Eclipse observations of solar radiation at a wave-length of 50 cm. Nature, 164, 635–637.
Christiansen, W. N., Yabsley, D. E., & Mills, B. Y. (1949b). Measurements of solar radiation at a wavelength of 50 centimetres during the eclipse of November 1, 1948. Australian Journal of Scientific Research, 2, 506–523.
Edge, D. O., & Mulkay, M. J. (1976). Astronomy transformed – The emergence of radio astronomy in Britain. London: Wiley.
Edge, D. O., Shakeshaft, J. R., McAdam, B., Baldwin, J. E., & Archer, S. (1959). A survey of radio sources at a frequency of 159 Mc/s. Memorandum of the Royal Astronomical Society, 68, 37–60.
Frater, R. H. (2005). Molonglo 40th Anniversary – After-dinner speech, 17 November 2005.
Goddard, B. R., Watkinson, A., & Mills, B. Y. (1960). An interferometer for the measurement of radio source sizes. Australian Journal of Physics, 13, 665–675.
Goss, W. M., Manchester, R. N., McAdam, W. B., & Frater, R. H. (1977). A new determination of the position of the Vela pulsar. Monthly Notices of the Royal Astronomical Society, 179, 51–54.
Hanbury-Brown, R., Jennison, R. C., & Das Gupta, M. K. (1952). Apparent angular sizes of discrete radio sources: Observations at Jodrell Bank, Manchester. Nature, 170, 1061–1063.
Home, R. W. (2006). The rush to accelerate: Early stages of nuclear physics research in Australia. Historical Studies in the Natural Sciences, 36(2), 213–141.
Jennison, R. C., & Das Gupta, M. K. (1953). Fine structure of the extra-terrestrial radio source Cygnus I. Nature, 172, 996–997.
Kragh, H. (1996). Cosmology and controversy. Pinceton University Press: Princeton.
L-3 Communications Seabeam Instruments. (2000). Multibeam sonar theory of operation [Online]. Seabeam Instruments. Accessed April, 2013, from http://www.ldeo.columbia.edu/res/pi/MB-System/sonarfunction/SeaBeamMultibeamTheoryOperation.pdf
Large, M. I., Vaughan, A. E., & Mills, B. Y. (1968). A pulsar supernova association? Nature, 220, 340–341.
Little, A. G., & Payne-Scott, R. (1951). The position and movement on the solar disk of sources of radiation at a frequency of 97 Mc/s. Australian Journal of Scientific Research, 4, 489–507.
Lorimer, D. R., Bailes, M., McLaughlin, M. A., Narkevic, D. J., & Crawford, F. (2007). A bright millisecond radio burst of extragalactic origin. Science, 318, 777–780.
Mauch, T., Murphy, T., Buttery, H. J., Curran, J., Hunstead, R. W., Piestrzynski, B., Robertson, J. G., & Salder, E. M. (2003). SUMSS: A wide-field radio imaging survey of the southern sky – II. The source catalogue. Monthly Notices of the Royal Astronomical Society, 342, 1117–1130.
McAdam, B. (2008). Molonglo observatory: Building the cross and MOST. Journal of Astronomical History and Heritage, 11, 63–70.
McCready, L. L., Pawsey, J. L., & Payne-Scott, R. (1947). Solar radiation at radio frequencies and its relation to sunspots. Proceedings of the Royal Society, A, 190, 357.
Messel, H. (1960). The New Radio Astronomy Centre of the University of Sydney. Nature, 188, 528–529.
Mills, B. Y. (1952a). Apparent angular sizes of discrete radio sources: Observations at Sydney. Nature, 170, 1063–1064.
Mills, B. Y. (1952b). The distribution of the discrete sources of cosmic radio radiation. Australian Journal of Scientific Research, 5, 266–287.
Mills, B. Y. (1952c). The positions of six discrete sources of cosmic radio radiation. Australian Journal of Scientific Research, 5, 245–463.
Mills, B. Y. (1955). The observation and interpretation of radio emission from some bright galaxies. Australian Journal of Physics, 8, 368–369.
Mills, B. Y. (1956). The radio source near the Galactic centre. The Observatory, 76, 65–67.
Mills, B. Y. (1960). On the identification of extragalactic radio sources. Australian Journal of Physics, 13, 550.
Mills, B. Y. (2006). An engineer becomes an astronomer. Annual Review of Astronomy and Astrophysics, 44, 1–15.
Mills, C. (2011). Euology read to Fureral Service of B.Y. Mills, Syndey.
Mills, B. Y., & Little, A. G. (1953). A high-resolution aerial system of a new type. Australian Journal of Physics, 6, 272.
Mills, B. Y., & Slee, O. B. (1957). A preliminary survey of radio sources in a limited region of the sky at the wavelength of 3.5 m. Australian Journal of Physics, 10, 162–194.
Mills, B. Y., & Thomas, A. B. (1951). Observations of the sources of radio-frequency radiation in the constellation of Cygnus. Australian Journal of Scientific Research A Physical Sciences, 4, 158.
Mills, B. Y., Slee, O. B., & Hill, E. R. (1958). A catalogue of radio sources between declinations +10° and −20°. Australian Journal of Physics, 11, 360.
Mills, B. Y., Slee, O. B., & Hill, E. R. (1960). A catalogue of radio sources between declinations −20° and −50°. Australian Journal of Physics, 13, 676.
Mills, B. Y., Slee, O. B., & Hill, E. R. (1961). A catalogue of radio sources between declinations −50° and −80°. Australian Journal of Physics, 14, 497.
Minnett, H. C. (1999). Light-weight air warning radar. In R. MacLeod (Ed.), The 'Boffins' of botany bay. Canberra: Australian Academy of Science.
Murphy, T., Mauch, T., Green, A., Hunstead, R. W., Piestrzynski, B., Kels, A. P., & Sztajer, P. (2007). The second epoch Molonglo Galactic Plane Survey: Compact source catalogue. Monthly Notices of the Royal Astronomical Society, 382, 382–392.
Pawsey, J. L. (1951). Letter from Pawsey to Ryle dated 1 May 1951. Sydney: Catalogue of papers and correspondence of Sir Martin Ryle (1918-1984), Churchill College Archives.
Pawsey, J. L. (1960). Draft letter from Pawsey to M.L.E. Oliphant – Undated, likely February 1960. Sydney: Pawsey Family Archive.
Robertson, J. G. (1991). The most and other radio telescopes. Australian Journal of Physics, 44, 729.
Ryle, M. (1950). Radio astronomy. Reports on Progress in Physics, 13, 184–246.
Ryle, M. (1955). Radio stars and their cosmological significance. The Observatory, 75, 137–147.
Ryle, M., & Scheuer, P. (1955). The spatial distribution and the nature of radio stars. Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, 230, 448–462.
Shakeshaft, J. R., Ryle, M., Baldwin, J. E., Elsmore, B., & Thomson, J. H. (1955). A survey of radio sources between declinations −38 and +83. Memorandum of the Royal Astronomical Society, 67, 101–154.
Smith, F. G. (1951). An accurate determination of positions of four radio stars. Nature, 168, 555.
Smith, F. G. (1952). Apparent angular sizes of discrete radio sources: Observations at Cambridge. Nature, 170, 1065.
Sullivan, W. T. (1982). Classics in radio astronomy. Dordrecht, Hollad: Reidel Publishing Company.
Sullivan, W. T. (1990). The entry of radio astronomy into cosmology: Radio stars and Martin Ryle’s 2C survey. In B. Bertotti, R. Balbinot, S. Bergia, & A. Messina (Eds.), Modern cosmology in retrospect. Cambridge: Cambridge University Press.
Sullivan, W. T. (2009). Cosmic noise: A history of early radio astronomy. Cambridge: Cambridge University Press.
Turtle, A. J., Campbell-Wilson, D., Bunton, J. D., Jauncey, D. L., Kesteven, M. J., Manchester, R. N., Norris, R. P., Story, M. C., & Reynolds, J. E. (1987). A prompt radio burst from supernova 1987A in the Large Magellanic Cloud. Nature, 327, 38–40.
Wallace, P. T., Peterson, B. A., Murdin, P. G., Danziger, I. J., Manchester, R. N., Lyne, A. G., Goss, W. M., Smith, F. G., Disney, M. J., Hartley, K. F., Jones, D. H. P., & Wellgate, G. W. (1977). Detection of optical pulses from the VELA pulsar. Nature, 266, 692–694.
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 2017 Springer International Publishing AG
About this chapter
Cite this chapter
Frater, R.H., Goss, W.M., Wendt, H.W. (2017). Bernie Mills: Cross-Type Telescopes and Discrete Radio Sources. In: Four Pillars of Radio Astronomy: Mills, Christiansen, Wild, Bracewell. Astronomers' Universe. Springer, Cham. https://doi.org/10.1007/978-3-319-65599-4_3
Download citation
DOI: https://doi.org/10.1007/978-3-319-65599-4_3
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-65598-7
Online ISBN: 978-3-319-65599-4
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)