Abstract
THE OBSERVATORY OF HARVARD COLLEGE, U.S.—We have received the Annual Report presented to the Visiting Committee of this Observatory by Prof. Pickering on December 6. The year has been one of unusual activity in the establishment, funds which had been liberally forthcoming from its friends having enabled both the equatorial and meridian circle to be regularly employed, and further having allowed of many researches of importance being conducted with the smaller instruments. With the large equatorial Prof. Pickering claims that he has succeeded in making a more extensive series of observations for position of the satellites of Mars at the last opposition than was obtained elsewhere, and states that Deimos was last seen at Harvard Observatory; the number of observed angles of position of Deimos was 825, and of Phobos 278, and that of observed distances 245. In addition to measures for position photometric observations were made, which appear to show that if the satellites possess a capacity for reflecting sunlight equal to that of the planet, Deimos may have a diameter of about six and Phobos of seven miles. It was noted at various observatories that Deimos appeared somewhat brighter in 1879 than at the preceding opposition in 1877, and in both years Prof. Pickering states it seems to have been brighter measured photometrically, and to have been seen more easily when it followed than when it preceded Mars.
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Our Astronomical Column . Nature 23, 321–322 (1881). https://doi.org/10.1038/023321a0
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DOI: https://doi.org/10.1038/023321a0