Astronomy and Astrophysics – Astrophysics
Scientific paper
Jan 1982
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982a%26a...105..400t&link_type=abstract
Astronomy and Astrophysics, vol. 105, no. 2, Jan. 1982, p. 400-404.
Astronomy and Astrophysics
Astrophysics
40
Colorimetry, Stellar Spectrophotometry, Sun, Ubv Spectra, Attenuation Coefficients, Diffraction, Faculae, Moon, Stellar Spectra, Sunspots, Ultraviolet Photometry, Visual Photometry
Scientific paper
A technique for comparing the sun with 25 bright stars in order to directly measure the sun's color indices is reported. The method involves the use of a variable entrance aperture, 10-95 microns, and two reflecting filters. Features of the photometer are described, and an alignment of the 4 m tube to better than one mm accuracy was achieved in fastening it to the GPO telescope at La Silla. Observations were made between Feb. 18-24, 1981, of the U-B and B-V values of the 25 reference stars, while observations of the sun were through a pinhole which reduced the brightness by eight magnitudes, and again to four magnitudes. Extinction coefficients, diffraction losses, and standard deviations were calculated yielding an accuracy of 0.02 for the U region, U-B accuracy of 0.18 magnitude, and a B-V accuracy of 0.686 magnitude. Although the measurements were outside expected values, an indication was found that sunspot faculae change the color indices less than 0.001 magnitude.
Schmidt-Kaler Theodor
Tueg H.
No associations
LandOfFree
A direct UBV color measurement of the sun does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A direct UBV color measurement of the sun, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A direct UBV color measurement of the sun will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1455109