Find more facts and information on our topic page about
Ring nebula
planetary nebula
planetary nebula A bright cloud of glowing gas and dust surrounding a highly evolved star. A planetary nebula forms when a red giant ejects its outer layers at speeds of about 10 km/s. The ejected gas is then ionized by ultraviolet light from the hot core of the star. As mass is lost this core is progressively exposed, and it ultimately turns into a white dwarf. Planetary nebulae are typically 0.5 l.y. across, and the amount of ejected material is 0.1 solar mass or more. Because the core is so hot the gas in the nebula is highly ionized. The planetary nebula exists for up to 100 000 years, during which time a sizable fraction of the star's mass is returned to interstellar space. Planetary nebulae were so named because they appeared to early observers to resemble a planetary disk. In fact the detailed shapes of planetary nebulae revealed by modern telescopes cover many different types, including ring-shaped (as in the Ring Nebula), dumbbell-shaped, or irregular. The various apparent shapes are now thought to be due to the angle at which we are viewing two lobes or cylinders of gas ejected in opposite directions from the central star in a
bipolar outflow.
Cite this article
Pick a style below, and copy the text for your bibliography.
 "The Birmingham Post (England)")
|
NIGHT SKY FOR AUGUST: Lie back and sweep the fading summer sky; There's lots to see in August including the spectacular Ring Nebula in the constellation of Lyra, reports Birmingham Astronomical Society.(Features)
Newspaper article from: The Birmingham Post (England); 7/30/2005; 700+ words
; ...sky Messier object M57, the famous Ring Nebula in the constellation of Lyra. Locate...appears as a tiny, bright torus (ring) of light but, set against a busy...object and the background sky. The Ring Nebula is a planetary nebula; a rather...
|
|
ADD TO NASA VIDEO FILE FOR JAN. 6, 1999 HUBBLE SPACE TELESCOPE HERITAGE IMAGE OF THE RING NEBULA
Transcript from: Regulatory Intelligence Data; 1/6/1999; ; 220 words
; ...the most famous of all planetary nebulae: the Ring Nebula (M57). In this October 1998...in the gas at the edge of the nebula; the dying central star floating in a blue haze of hot gas. The nebula is about light- years from Earth...
|
|
Chandra reveals ring in nebula.
Newspaper article from: The Boston Herald; 9/29/1999; ; 434 words
; ...an image taken of the Crab Nebula, the spectacular remains of...never before seen: a brilliant ring around the nebula's heart. "The inner ring is unique. It has never been...said. The image shows tilted rings or waves of high-enegy particles...
|
|
BEHLEN PUBLIC NIGHT SEPT. 29 TO VIEW JUPITER, LYRA'S RING NEBULA
News Wire article from: US Fed News Service, Including US State News; 9/15/2006; 681 words
; ...up outside the observatory. These include the moon, two kinds of star clusters, double or multiple stars, and the Ring Nebula in Lyra. Early in the evening it will also be possible to observe Jupiter with one of the small telescopes. At various...
|
|
X-ray ring may provide clues to nebula's energy.
Newspaper article from: The Florida Times Union; 9/29/1999; 487 words
; ...A never-before-seen ring of X-rays has been discovered...the heart of the massive Crab nebula in space, NASA announced yesterday. The ring was revealed by the 2-month...the year 1054. "The inner ring is unique," Jeff Hester of...
|
|
NASA: Briefing Sept. 28 presents Chandra discovery of of ring around cosmic powerhouse in Crab Nebula.
M2 Presswire; 9/24/1999; 550 words
; ...presents Chandra discovery of ring around cosmic powerhouse in Crab Nebula (C)1994-99 M2 COMMUNICATIONS...Sept. 28, reveals a brilliant ring around a cosmic powerhouse at...SW, Washington, DC. The ring is the first such structure...
|
|
Hubble reveals nebula's secrets
Newspaper article from: The Scotsman; 1/11/1999; ; 587 words
; ...earth. Now the secrets of Ring Nebula's otherworldly beauty have...pictures confirm that the "ring", first detected more than...Lyra, and only looks like a ring because we are viewing it almost...speck at the centre of the ring was once a star bigger than...about the shape of planetary ...
|
 "Daily Record (Glasgow, Scotland)")
|
LONG LOOK AT BIG EYE IN THE SKY; FOCUS ON SPACE: HUBBLE TELESCOPE REVEALS SPECTACULAR NEBULA PICTURE.(News)
Newspaper article from: Daily Record (Glasgow, Scotland); 1/11/1999; ; 649 words
; ...the constellation of Lyra. But the Ring Nebula - one of the most spectacular objects...now pictures of the glowing smoke-ring of blue, green and red gas have been...Howard Bond said: "We chose the Ring Nebula as our first new target, in...
|
 "The Mail on Sunday (London, England)")
|
The web's final frontier; SPACED OUT: From nebulas to galaxies and supergiant stars, Worldwide Telescope covers it all.
Newspaper article from: The Mail on Sunday (London, England); 5/25/2008; 700+ words
; ...of times the size ofsuns, and whether or not the Crab Nebula's supernova was seen by NativeAmericans in 1054. You...year-old Benjamin from Toronto's description of the Ring Nebula:'It is also known as N157, according to the free encyclopedia...
|
|
|
UNIVERSITY OF MISSOURI SCIENTIST DISCOVERS 'FIREWORK' DISPLAY IN HELIX NEBULA
News Wire article from: US Fed News Service, Including US State News; 7/21/2009; 684 words
; ...ejected from the dying star Helix Nebula. A high-resolution near...the inner edge to the outer ring of the nebula. "The knots...Helix Nebula is a planetary nebula, and also is one of the closest nebulae to Earth. The process of developing a nebula occurs slowly over a period...
|
|
Ring nebula
Book article from: The Columbia Encyclopedia, Sixth Edition
Ring nebula planetary nebula in the northern constellation Lyra; cataloged as M57 or NGC 6720. It is perhaps the most famous and beautiful nebula of this type. Its name describes the appearance of the expanding...
|
|
Ring Nebula
Book article from: A Dictionary of Astronomy
Ring Nebula A 9th-magnitude planetary nebula about 2000 l.y...small telescopes the shell looks like an elliptical smoke ring 70″ × 150″ across. The ring is expanding at 19 km/s. Observations...
|
|
Nebula
Encyclopedia entry from: UXL Encyclopedia of Science
Nebula Bright or dark clouds...the stars) are called nebulae. Nebula, Latin for "cloud...famous of these is the Ring Nebula in the constellation...as common as emission nebulae. A reflection nebula is a bluish cloud containing...
|
|
|
planetary nebula
Book article from: A Dictionary of Astronomy
planetary nebula A bright cloud of glowing...white dwarf. Planetary nebulae are typically 0.5 l...detailed shapes of planetary nebulae revealed by modern telescopes...different types, including ring-shaped (as in the Ring Nebula), dumbbell-shaped...
|
|
|
Saturn Nebula
Book article from: A Dictionary of Astronomy
Saturn Nebula An 8th-magnitude planetary nebula 3000 l.y. away in Aquarius, also known as NGC 7009. In shape it appears superficially similar to Saturn with its rings.
|
