Brian May is the famous guitarist of the Queen, Freddie Mercury's rock band (and one of my favourite band!), but is also an astrophysicist!He wasborn 19 July 1947 in Twickenham, London. He studied mathematics and physics at Imperial College, where he started also the PhD program, but he abandoned when Queen became a succesful band in the world. He completed his PhD in 2007(5), but he did not forget his research activity, indeed he written with Patrick Moore and Chris Lintott Bang! – The Complete History of the Universe (2006)... but... just a moment... research activity? Yeah!
In 1972 and 1973 two papers signed by Mr.May are be published: MgI Emission in the Night-Sky Spectrum and An Investigation of the Motion of Zodiacal Dust Particles (Part I), written with Mr.Hicks and Mr.Reay.
May and collegues are interestend in zodiacal light, in particular in MgI spectrum, near the 5183.62 Å wavelength.
The importance of this kind of studies is that the MgI and MgII formation is one feature in the interaction between atmosphere and star radiations(2, 3).
But go to the papers: in order to determine the absorbtion lines from zodiacal light, Brian and friends used the Fabry-Perot interferometer:
The method was to sample, for 48 s, each of up 18 points acrossthe spectral interval. Pulse counting electronics and a line printer recordedthe signal levelat each sample point. A second channel of pulse counting monitored the overall sky background over a widewaveband, thus allowing correction forfluctation in sky transparency. The resolving power of the interferometer was 3500, corresponding to an instrumental profile width of 1.5 Å.Obesrvation time is September, October 1971 and April 1972 from the observatory at Izana on Tenerife, Canary Islands.
The typical scans obtained by researchers are like:
In the following figure the orbital structure of Mg(4):
MgI term diagram(4)
Radiative recombination of Mg+ with an electron, the mechanism suggested by Anderson and Barth(1) governing the daytime balance between Mg and Mg+, is the most likely cause of the emission. It would be expected that other MgI lines, such as the other lines of the 3p3P2-4s3S triplet 5172.68 Å and 5167.33 Å, are present with 5183.62 Å. The intercombination line at 4571.1 Å connecting 3P to the ground S state should also be present.Brian May, we know, is not only an astronomer and a writer, but also a musician, so I conclude this briefly post with a Queen's song written by Brian, Long Away:
P.S.: sorry for the wrong post (Brian), but I pushed enter button when writing title...
Official biography
Brian May - Guitarist and Physicist
(1) James G. Anderson, Charles A. Barth, Rocket Investigation of the Mg I and Mg II Dayglow, Journal of Geophysical Research, Vol. 76, No. 16, 3723-3732 (1971)
(2) Altrock, Richard C., Cannon, C. J, The Formation of MgI 4571 Å in the Solar Atmosphere. I: A Model Analysis of a One-Dimensional Static Atmosphere, Solar Physics, Volume 26, Issue 1, pp.21-29 (1972)
(3) Altrock, Richard C., Cannon, C. J, The formation of MG I 4571 Å in the solar atmosphere. V - The multi-dimensional structure of the photosphere and low chromosphere, Solar Physics, vol. 42, June 1975, p. 289-302 (1975)
(4) Carlsson, M., Rutten, R. J., Shchukina, N. G., The formation of the MG I emission features near 12 microns, Astronomy and Astrophysics, vol. 253, no. 2, Jan. 1992, p. 567-585 (1992)
(5) B. May, A Survey of Radial Velocities in the Zodiacal Dust Cloud (2007), also on Amazon, Google Books, facebook
Hicks, T., May, B., & Reay, N. (1972). MgI Emission in the Night Sky Spectrum Nature, 240 (5381), 401-402 DOI: 10.1038/240401a0
Hicks, T., May, B., & Reay, N. (1972). An investigation of the motion of zodiacal dust particles-1. Radial velocity measurements on Fraunhofer line profiles Monthly Notices of the Royal Astronomical Society, Vol. 166, p. 439-448 (5381), 401-402 Bibliographic code: 1974MNRAS.166..439H
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