The Dumbbell Nebula

The Dumbbell Nebula ­— also known as Messier 27 or NGC 6853 — is a typical planetary nebula and is located in the constellation Vulpecula (The Fox). The distance is rather uncertain, but is believed to be around 1,200 light-years. It was first described by the French astronomer and comet hunter Charles Messier who found it in 1764 and included it as no. 27 in his famous list of extended sky objects [2] .Despite its class, the Dumbbell Nebula has nothing to do with planets. It consists of very rarified gas that has been ejected from the hot central star (well visible on this photo), now in one of the last evolutionary stages. The gas atoms in the nebula are excited (heated) by the intense ultraviolet radiation from this star and emit strongly at specific wavelengths.

This image is the beautiful by-product of a technical test of some FORS1 narrow-band optical interference filtres. They only allow light in a small wavelength range to pass and are used to isolate emissions from particular atoms and ions. In this three-colour composite, a short exposure was first made through a wide-band filtre registering blue light from the nebula. It was then combined with exposures through two interference filtres in the light of double-ionized oxygen atoms and atomic hydrogen. They were colour-coded as “blue”, “green” and “red”, respectively, and then combined to produce this picture that shows the structure of the nebula in “approximately true” colours.

They are three-colour composite based on two interference ([OIII] at 501 nm and 6 nm FWHM — 5 min exposure time; H-alpha at 656 nm and 6 nm FWHM — 5 min) and one broadband (Bessell B at 429 nm and 88 nm FWHM; 30 sec) filtre images, obtained on September 28, 1998, during mediocre seeing conditions (0.8 arcsec). The CCD camera has 2048 x 2048 pixels, each covering 24 x 24 µm and the sky fields shown measure 6.8 x 6.8 arcminutes and 3.5 x 3.9 arcminutes, respectively. North is up; East is left.

Crédit:

ESO/I. Appenzeller, W. Seifert, O. Stahl

À propos de l'image

Identification:eso9846a
Type:Observation
Date de publication:7 octobre 1998
Communiqués de presse en rapport:eso9846
Taille:2044 x 2042 px

À propos de l'objet

Nom:Dumbbell Nebula, M 27, Messier 27, NGC 6853
Type:Milky Way : Nebula : Type : Planetary
Distance:1200 années lumière
Constellation:Vulpecula
Catégorie:Nebulae

Mounted Image

Formats des images

Grand JPEG
1,7 Mio
JPEG taille écran
258,8 Kio

Zoomable


Fonds d'écran

1024x768
262,0 Kio
1280x1024
446,2 Kio
1600x1200
744,2 Kio
1920x1200
1,0 Mio
2048x1536
1,1 Mio

Coordinates

Position (RA):19 59 36.41
Position (Dec):22° 43' 16.00"
Field of view:6.76 x 6.82 arcminutes
Orientation:North is 0.0° left of vertical

Couleurs & filtres

DomaineLongueur d'ondeTélescope
Visible
u
361 nmVery Large Telescope
FORS1
Visible
B
429 nmVery Large Telescope
FORS1
Visible
Oiii
501 nmVery Large Telescope
FORS1
Visible
HeII
472 nmVery Large Telescope
FORS1
Visible
R
655 nmVery Large Telescope
FORS1
Visible
H-alpha
656 nmVery Large Telescope
FORS1

 

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