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: http://www.arcetri.astro.it/~palla/ANDREAIMMAGINI/ISM/crl618.html
Дата изменения: Tue Jan 30 19:55:44 2001 Дата индексирования: Sat Dec 22 07:57:47 2007 Кодировка: Поисковые слова: comet tail |
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
![]() Credit: Susan R. Trammell (UNC Charlotte) et al., ESAIC, HST, ESA, NASA |
Explanation: CRL 618 may look to some like an Olympian declaring victory. Only a few hundred years ago, however, CRL 618 appeared as a relatively modest red giant star. Since then it has run out of core material to fuse and so has started to become a planetary nebula. In its current proto-planetary nebula phase, CRL 618 is evolving quickly, expelling hot gasses in complex jets and rings moving outwards faster than 700,000 kilometers per hour. In a few thousand years, the glowing core of the cool red giant will be bare, revealing a hot white dwarf star. Much remains unknown about planetary nebulae formation, including details of how geometries like this form. Perhaps one day some part of this nebula will be able to declare victory - CRL 618 has an extraordinary abundance of carbon-chain molecules. |
Authors & editors:
Robert
Nemiroff
(MTU) &
Jerry Bonnell (USRA)
NASA Technical Rep.:
Jay Norris.
Specific rights apply.
A service of:
LHEA at
NASA/GSFC
&
Michigan Tech. U.