Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.astronet.ru/db/xware/msg/apod/2004-12-03
Дата изменения: Fri Dec 3 14:20:28 2004
Дата индексирования: Sat Dec 29 01:07:07 2007
Кодировка:
I Zwicky 18: Young Galaxy
Astronomy Picture of the Day
    


I Zwicky 18: Young Galaxy
<< Yesterday 3.12.2004 Tomorrow >>
I Zwicky 18: Young Galaxy
Credit: Y. Izotov (Main Astronomical Obs., Ukraine), T. Thuan (Univ. Virginia), ESA, NASA
Explanation: The Milky Way is an ordinary 12 billion year old spiral galaxy, and even our middle-aged Sun is pushing 4.5 billion years. But all the stars in dwarf galaxy I Zwicky 18 are much younger. In fact, based on Hubble Space Telescope image data, that galaxy's first stars formed only about 500 million years ago, making it the youngest known galaxy. In this view, the bright knots are the two major star forming regions of I Zwicky 18, embedded in expanding filaments of glowing interstellar gas. Scattered, much older background galaxies are seen as small red blobs, and a companion galaxy lies just beyond the upper right corner of the cropped picture. Astronomers believe that diminutive I Zwicky 18 resembles the earliest galaxies formed, but also want to understand how such a young galaxy can be only 45 million light-years away - surrounded by mature galaxies in an aging Universe. The tiny galaxy itself is a mere 3,000 light-years across.

January
February
March
April
May
June
July
August
September
October
November
December
 < December 2004  >
Mo Tu We Th Fr Sa Su


12345
6789101112
13141516171819
20212223242526
2728293031

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: dwarf galaxy
Publications with words: dwarf galaxy
See also:
All publications on this topic >>