Physical Sciences

Research Aids for the Nineteenth Century

This is a brief outline of the development of string theory, the details of which will eventually fill many large volumes written by many people directly and indirectly involved in this rich and fascinating story.

From the Multi-Repository Mathematics Collections site you will gain access to three of the most significant mathematics collections digitally available: The Mathematics Collection from Cornell, the Mathematics Collection from Göttingen, and the University of Michigan's Historical Math Collection. From this access point you will be able to search across all three of these collections, and examine results as you would normally using the University of Michigan's user interface. It is important to point out that the University of Göttingen has only one item for which a fulltext search can be performed, but bibliographic searches across the collection are possible.

The Archives of American Mathematics (AAM) is one of the collection components available at the Center for American History's Research and Collections Division. AAM is dedicated to preserving the records of American mathematicians and American mathematical organizations for use by mathematicians, historians, and others interested in the history and development of American mathematics and science.

Until quite recently, I though that the first published HR diagram was constructed by Ejnar Hertzsprung for the stars of the Pleiades. Already in 1908, when Hertzsprung (then still an amateur astronomer with training in photochemistry) visited Karl Schwarzschild at Göttingen, he brought with him a working version with photographic magnitudes plotted against effective wavelengths. To determine the latter quantity, nowadays replaced by spectral type or color index, Hertzsprung attached a coarse diffraction grating before the objective so that an ordinary stellar image on the photographic plate was accompanied by a very short first-order spectrum on either side. The separation of the most intense parts of these spectra then directly translated into the effective wavelength of the star's light. However, this first Hertzsprung attempt to visualize the relation between luminosities and colors of stars suffered from a systematic error due to influence of the secondary spectrum of the objective. It was not until 1911, when the satisfactory version of the diagram was presented (Publ. Astrophys. Observ. Potsdam 22, 1, 1911) together with a color-magnitude diagram for another winter cluster, the Hyades.

n the Third Annual Report of the Henry Draper Memorial, attention is called to the fact that the K line in the spectrum of Zeta Ursae Majoris occasionally appears double. The spectrum of this star has been photographed at the Harvard College Observatory on seventy nights and a careful study of the results has been made by Miss. A. C. Maury, a niece of Dr. Draper. The K line is clearly seen to be double in the photographs taken on March 29, 1887, on May 17, 1889 and on August 27 and 28, 1889. On many other dates the line appeared hazy, as if the components were slightly separated, while at other times the line appears to be well defined and single.

Goddard Space Flight Center Library

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Mathematics represents a high level of abstraction attained by the human mind. In India, mathematics has its roots in Vedic literature which is nearly 4000 years old. Between 1000 B.C. and 1000 A.D. various treatises on mathematics were authored by Indian mathematicians in which were set forth for the first time, the concept of zero, the techniques of algebra and algorithm, square root and cube root.

Last year saw two interesting events in the world of double stars, both of them connected with an astronomer's old friend in the Big Dipper. While the early history of double star astronomy had to be completely rewritten after an examination of 17th century Italian manuscripts, its future at the beginning of the next millennium was briefly unveiled by the amazing precision of a new astrometric instrument, which will soon eliminate the difference between spectroscopic and visual binaries.

X-ray Astronomy at Goddard:
Early History

From 1965 to 1972 there were over a dozen balloon-borne experiments (mostly from New Mexico), including the first such to take place from Australia (1966), one in which hard X-ray emission was discovered (albeit with crude angular resolution) from a region towards the galactic center whose centroid is located among subsequently identified sources GX1+4, GX3+1, and GX5-1. A balloon-borne experiment in 1968 was based on the multi-anode multi-layer xenon gas proportional chamber that had recently been developed in our lab and represented the first use of such a high performance instrument for X-ray astronomy.