Imaginea Astronomica a Zilei

Descopera cosmosul! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

October 27, 1998
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

Henrietta Leavitt Calibrates the Stars
Credit: AAVSO

Explicatie: (Edit) 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.

Imaginea de maine: NGC 6210: A Turtle in Space


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Autori & editori: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
Reprezentanti tehnici NASA: Jay Norris. Specific rights apply.
Un serviciu al: LHEA at NASA/ GSFC
&: Michigan Tech. U.