Henry Draper Catalog

(HD Catalog) A star catalog in nine volumes compiled by Annie J. Cannon and E.C. Pickering of the Harvard College Observatory and published 1918–24 as part of the Harvard Annals. It was the first catalog to assign stars to spectral classes as well as giving their positions and magnitudes. The catalog (a memorial to Henry Draper, a distinguished physician who, as an amateur astronomer, pioneered in the field of astronomical photography) was financed through a fund set up by Draper's wife after his death in 1882. It lists 225 300 stars for the epoch 1900.0, each allocated a spectral type according to the Harvard classification. The Henry Draper Extension (HDE), 1925–36, lists a further 133 700 stars. The entire catalog, of which the latest version appeared in 1985, is currently being reclassified on the MK system by a team from the University of Michigan led by Nancy Houk. Work on this publication, the Michigan Catalog of Two-dimensional Spectral Types for the HD Stars, began 1975.

单词	henry draper catalog
释义	Henry Draper Catalog Henry Draper Catalog (HD Catalog) A star catalog in nine volumes compiled by Annie J. Cannon and E.C. Pickering of the Harvard College Observatory and published 1918–24 as part of the Harvard Annals. It was the first catalog to assign stars to spectral classes as well as giving their positions and magnitudes. The catalog (a memorial to Henry Draper, a distinguished physician who, as an amateur astronomer, pioneered in the field of astronomical photography) was financed through a fund set up by Draper's wife after his death in 1882. It lists 225 300 stars for the epoch 1900.0, each allocated a spectral type according to the Harvard classification. The Henry Draper Extension (HDE), 1925–36, lists a further 133 700 stars. The entire catalog, of which the latest version appeared in 1985, is currently being reclassified on the MK system by a team from the University of Michigan led by Nancy Houk. Work on this publication, the Michigan Catalog of Two-dimensional Spectral Types for the HD Stars, began 1975.
随便看	saves a bundle saves a lot of money on saves bacon saves blushes saves breath save set identifier saves face saves for saves for another saves for another occasion saves for a rainy day saves for marriage saves from saves her blushes saves her face saves her from saves her hide save skin save somebody's bacon save somebody's blushes save somebody's hide save somebody's neck save somebody's skin save somebody's/your neck/skin/hide save some money on