gingadan.com

NGC 6720 (Ring Nebula, M57)


Home > Messier > NGC6720
Down
Movie

NGC 6720, M57
Ring Nebula (リング星雲)
Planetary Nebula (惑星状星雲)
Nb PN


別名 (Other names)
PK 63+13.1, GC 4447, Messier 57, 環状星雲, ドーナツ星雲

明るさ (Brightness)
8.8等級

星座 (Constellation)
こと座 (Lyr) (Lyra)

距離 (Distance)
2,300光年 (2,300 light-years)

環状星雲(Ring Nebula 、M57、NGC6720)はこと座にある惑星状星雲。距離は2,300光年。
リング状の特徴的な姿をしており、惑星状星雲の中では最も有名な天体の一つで、「リング星雲」「ドーナツ星雲」の別名がある。惑星状星雲としてはM27に次いで発見された。

星雲の中心には白色矮星が存在し、この星から数千年前に放出されたガスが白色矮星からの紫外線を受けて蛍光灯のように輝いている。リング部分の青い色はヘリウム、緑色は酸素、赤色は窒素の輝線スペクトルである。

NGC 6720 (Ring Nebula, M57) is a planetary nebula located 2,300 light years from the Earth in the constellation Lyra.

NGC 6720 (Ring Nebula, M57) : Picture

M57 (Ring Nebula)
M57 (Ring Nebula)
(C) NASA, ESA, and the Hubble Heritage (STScI / AURA)- ESA / Hubble Collaboration
Except for the rings of Saturn, the Ring Nebula (M57) is probably the most famous celestial band. Its classic appearance is understood to be due to our own perspective, though. The recent mapping of the expanding nebula's 3-D structure, based in part on this clear Hubble image, indicates that the nebula is a relatively dense, donut-like ring wrapped around the middle of a football-shaped cloud of glowing gas. The view from planet Earth looks down the long axis of the football, face-on to the ring. Of course, in this well-studied example of a planetary nebula, the glowing material does not come from planets. Instead, the gaseous shroud represents outer layers expelled from the dying, once sun-like star, now a tiny pinprick of light seen at the nebula's center. Intense ultraviolet light from the hot central star ionizes atoms in the gas. In the picture, the blue color in the center is ionized helium, the cyan color of the inner ring is the glow of hydrogen and oxygen, and the reddish color of the outer ring is from nitrogen and sulfur. The Ring Nebula is about one light-year across and 2,000 light-years away.

M57 (Ring Nebula)
M57 (Ring Nebula)
(C) Hubble Heritage Team (AURA/STScI/NASA/ESA)

M57 (Ring Nebula)
M57 (Ring Nebula)
(C) Composite Image Data - Subaru Telescope (NAOJ), Hubble Legacy Archive; Processing and additional imaging - Robert Gendler

Ring Nebula
The region around the Ring Nebula (Hubble/LBT composite)
(C) NASA, ESA, C. Robert O’Dell (Vanderbilt University), and David Thompson (LBTO)
This image is a composite of the Ring Nebula (Messier 57). This combines new Hubble Wide Field Camera 3 data with observations of the nebula’s outer halo from the Large Binocular Telescope (LBT) in Arizona, USA. In this image, the knotty, turbulent space around the nebula shows up dramatically, creating an almost psychedelic effect.

The Large Binocular Telescope is part of the Mount Graham International Observatory in Arizona.

M57 (Ring Nebula)
M57 (Ring Nebula)
(C) Adam Block/NOAO/AURA/NSF
The ring nebula is probably one of the most famous deep sky objects. Generally when amateurs begin their telescopic journey, after the Orion Nebula, the Ring is one of the next objects on the list. Even through a small telescope its bright and distinctive shape sets it apart from a typical field of stars. An image such as this, when acquired using a CCD camera, shows both the detail and color of this remarkable object. Like others of its type, the Ring Nebula is the expelled outer envelope of an aged star that has now reached its final stages of life. This bubble of gas is more than 2,000 light years away and therefore is itself more than 1 lightyear in diameter. The white dwarf (central star which is the naked core of the original sun-like whole) is extremely hot (100,000K) and emits copious amounts of UV radiation. This emission excites various gases in the bubble and makes them glow (not unlike a neon light). The sphere of gas continues to expand, and if we could watch for the next 300,000 years the bubble would thin and disintegrate leaving the cold dark husk of the cooled white dwarf.

Technically a better description of this "bubble" of gas is something a bit more cylindrical. In this case we are looking down the major axis (shaft) of the short tube. Previous episodes of mass loss can be seen in concentric layers far from the brightest portion. Please visit the NOAO M57 to see a similar picture created with the Kitt Peak 2.1-meter telescope. If we were able to look at the ring nebula from the side (rotate 90 degrees), it would look like M76. Also note the galaxy, IC 1296, which floats majestically in the background.

M57 (Ring Nebula)
M57 (Ring Nebula)
(C) Daniel Duggan & the ESA/ESO/NASA Photoshop FITS Liberator
Image taken with Faulkes Telescope North, Hawaii.
LRGB image, 90 second exposures (per filter)
H-alpha layer used as Luminance.
Processed with The FITS Liberator & Photoshop CS2

Ring Nebula Deep Field
Ring Nebula Deep Field
(C) Vicent Peris (DSA / OAUV / PixInsight), Jack Harvey (DSA / SSRO), Steve Mazlin (DSA / SSRO), Jose Luis Lamadrid (DSA / ceFca), Ana Guijarro (CAHA), RECTA, DSA.

M57, NGC6720, Ring Nebula
M57, NGC6720, Ring Nebula
(C) N.A.Sharp, REU program/NOAO/AURA/NSF

Ring Nebula, M57
Four views of the Ring Nebula, M57
(C) NOAO/AURA/NSF
The Ring Nebula, Messier object 57 (M57), NGC 6720, in the constellation Lyra. This image shows four different views of the nebula as seen at four different wavelengths (colors of light). The use of multi-color imaging helps to reveal physical conditions in the nebula, as different colors of light are emitted by different gases in varying physical states. These pictures were taken with the Kitt Peak 2.1-meter telescope in 1973, using the 40cm Carnegie image tube and an enhanced two inch photographic plate, by Dr Larry Goad. M57 was the first of the class called planetary nebulae to be discovered. It is about 3,000 light-years away and about a light-year across.

M57 M57
M57 (Ring Nebula)
(C) NASA/ESA
M57 (Ring Nebula)
(C) NASA/ESA
M57 M57
M57 (Ring Nebula)
(C) Subaru Telescope (NAOJ)
M57 (Ring Nebula)
(C) NASA/ESA
M57 M57
M57 (Ring Nebula)
(C) NOAO
M57 (Ring Nebula)
(C) NASA/ESA
M57 M57
M57 (Ring Nebula)
(C) NOAO
M57 (Ring Nebula)
(C) NOAO
Ring Nebula M57
Ring Nebula Deep Field
(C) Vicent Peris
M57, NGC6720, Ring Nebula
(C) NOAO
Ring Nebula M57
Halos Around the Ring Nebula
(C) Subaru 8.3-m Telescope, NAOJ
M57 (Ring Nebula)
(C) H. Bond, R. Ciardullo, NASA
Up
Up

NGC 6720 (Ring Nebula, M57) : Movie

Hubblecast 66: Hubble uncovers the secrets of the Ring Nebula — The ESA astronomy podcast
This episode of the Hubblecast explores the Ring Nebula (Messier 57). Although this nebula is one of the most famous objects in our skies, more than 200 years after its discovery astronomers are still unveiling some of its secrets.

The Ring Nebula was discovered in the late 18th century, but its true shape and structure has remained unclear. Now, a team of astronomers has used the NASA/ESA Hubble Space Telescope, alongside existing ground-based data, to explore the Ring Nebula in depth. The astronomers wanted to better understand the nebula's structure, evolution, physical conditions, and motion — and it turns out that the Ring Nebula is not actually very ring-shaped after all.

Exploring the Structure of the Ring Nebula
The Ring Nebula, captured in detail by Hubble's gaze, is actually a three-dimensional object. Zoom in to the constellation Lyra, where we find the nebula, and learn about its complex shape.
Up
Home > Messier > NGC6720
Up

「ウィキペディア(wikipedia):フリー百科事典」より文章引用。
環状星雲. (2014, January 7). In Wikipedia.
gingadan.com ブログパーツ