A smouldering star

This new image, snapped by NASA/ESA Hubble Space Telescope, shows the star HD 184738, also known as Campbell’s hydrogen star. It is surrounded by plumes of reddish gas — the fiery red and orange hues are caused by glowing gases, including hydrogen and nitrogen.

HD 184738 is at the centre of a small planetary nebula. The star itself is known as a  [WC] star, a rare class resembling their much more massive counterparts — Wolf-Rayet stars. These stars are named after two French astronomers, Charles Wolf and Georges Rayet, who first identified them in the mid-nineteenth century.

Wolf-Rayet stars are hot stars, perhaps 20 times more massive than the Sun, that are rapidly blowing away material and losing mass. [WC] stars are rather different: they are low-mass Sun-like stars at the end of their lives. While these stars have recently ejected much of their original mass, the hot stellar core is still losing mass at a high rate, creating a hot wind. It is these winds that cause them to resemble Wolf-Rayet stars.

However, astronomers can look more closely at the composition of these winds to tell the stars apart; [WC] stars are identified by the carbon and oxygen in their winds. Some true Wolf-Rayet stars are rich in nitrogen instead, but this is very rare among their low-mass counterparts.

HD 184738 is also very bright in the infrared part of the spectrum, and is surrounded by dust very similar to the material that the Earth formed from. The origin of this dust is uncertain.

A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Jean-Christophe Lambry.

This caption was revised on 18/09/2013 to more accurately describe this image.

Credit:

ESA/Hubble & NASA
Acknowledgement: Jean-Christophe Lambry

About the Image

Id:potw1337a
Type:Observation
Release date:16 September 2013, 10:00
Size:501 x 501 px

About the Object

Name:Campbell's star, HD 184738
Type:• Local Universe : Star : Type : Wolf-Rayet
• X - Hubble Images Videos
• X - Stars Images/Videos
Constellation:Cygnus


Image Formats

Large JPEG
85.6 KB
Screensize JPEG
185.7 KB

Zoomable


Wallpapers

1024x768
202.7 KB
1280x1024
289.8 KB
1600x1200
368.2 KB
1920x1200
393.4 KB
2048x1536
502.8 KB

Coordinates

Position (RA):19 34 45.14
Position (Dec):30° 31' 1.49"
Field of view:0.42 x 0.42 arcminutes
Orientation:North is 19.8° left of vertical
View in WorldWide Telescope:
View in WorldWide Telescope

Colours & filters

BandWavelengthTelescope
Infrared
Z
953 nm Hubble Space Telescope
WFPC2
Optical
R
658 nm Hubble Space Telescope
WFPC2
Optical
I
673 nm Hubble Space Telescope
WFPC2
Optical
V
555 nm Hubble Space Telescope
WFPC2
Optical
B
502 nm Hubble Space Telescope
WFPC2

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