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.

Källa:

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

Om bilden

ID:eso9846a
Typ:Observation
Publiceringsdatum:7 oktober 1998
Relaterade pressmeddelanden:eso9846
Storlek:2044 x 2042 px

Om objektet

Namn:Dumbbell Nebula, M 27, Messier 27, NGC 6853
Typ:Milky Way : Nebula : Type : Planetary
Avstånd:1200 ljusår
Constellation:Vulpecula
Kategori:Nebulae

Bildformat

Originalstorlek
23,9 MB
Stor jpeg
1,7 MB
Skärmstor jpeg
258,8 kB

Zoombar


Skrivbordsunderlägg

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

Koordinater

Position (RA):19 59 36.41
Position (Dec):22° 43' 16.00"
Field of view:6.76 x 6.82 arcminutes
Orientering:Nord är 0.0° vänster om lodrätt

Färger och filter

BandVåglängdTeleskop
Synligt ljus
u
361 nmVery Large Telescope
FORS1
Synligt ljus
B
429 nmVery Large Telescope
FORS1
Synligt ljus
Oiii
501 nmVery Large Telescope
FORS1
Synligt ljus
HeII
472 nmVery Large Telescope
FORS1
Synligt ljus
R
655 nmVery Large Telescope
FORS1
Synligt ljus
H-alpha
656 nmVery Large Telescope
FORS1