Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.astronet.ru/db/xware/msg/apod/2000-09-03
Дата изменения: Tue Dec 19 00:00:00 2000
Дата индексирования: Sat Dec 29 06:49:17 2007
Кодировка:

Поисковые слова: universe
Henrietta Leavitt Calibrates the Stars
Astronomy Picture of the Day
    


Henrietta Leavitt Calibrates the Stars
<< Yesterday 3.09.2000 Tomorrow >>
Henrietta Leavitt Calibrates the Stars
Credit: AAVSO
Explanation: Humanity's understanding of the relative brightness and variability of stars was revolutionized by the work of Henrietta Swan Leavitt (1868-1921). Working at Harvard College Observatory, Leavitt precisely calibrated the photographic magnitudes of 47 stars to which all other stars could be compared. Leavitt discovered and cataloged over 1500 variable stars in the nearby Magellanic Clouds. From this catalog, Leavitt discovered that brighter Cepheid variable stars take longer to vary, a fact used today to calibrate the distance scale of our universe.

January
February
March
April
May
June
July
August
September
October
November
December
 < September 2000  >
Mo Tu We Th Fr Sa Su




123
45678910
11121314151617
18192021222324
252627282930
Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.

Based on Astronomy Picture Of the Day

Publications with keywords: scientist - Henreitta Leavitt - star
Publications with words: scientist - Henreitta Leavitt - star
See also:
All publications on this topic >>