BHR 71 Dark Cloud

BHR 71 Dark Cloud

New Star Formation in Musca

Constellation: Musca
Ra: 12h 01m 37s
Dec: -65d 08m 49s
Distance: 600 light years
Image Size: 27' x 30'
North: Up, East Left



BHR 71 is a small, dark cloud in the southern constellation of Musca about 600 light years distant. It has been studied with the Spitzer space telescope at infrared wavelengths, which penetrate the dense dust to see underlying stars that are mostly hidden at visible wavelengths. The following composite image clearly shows this. The “jet” shown below from the VLT image is also present in my image above. Please read about BHR 71 from Caltech at

“Two rambunctious young stars are destroying their natal dust cloud with powerful jets of radiation, in an infrared image from NASA’s Spitzer Space Telescope. The stars are located approximately 600 light-years away in a cosmic cloud called BHR 71. 

In visible light (left), BHR 71 is just a large black structure. The burst of yellow light toward the bottom of the cloud is the only indication that stars might be forming inside. 

In infrared light (middle), the baby stars are shown as the bright yellow smudges toward the center. Both of these yellow spots have wisps of green shooting out of them. The green wisps reveal the beginning of a jet. Like a rainbow, the jet begins as green, then transitions to orange, and red toward the end. 

The combined visible-light and infrared composite (above) shows that a young star’s powerful jet is responsible for the rupture at the bottom of the dense cloud in the visible-light image. Astronomers know this because burst of light in the visible-light image overlaps exactly with a jet spouting-out of the left star, in the infrared image. 

The jets’ changing colors reveals a cooling effect, and may suggest that the young stars are spouting out radiation in regular bursts. The green tints at the beginning of the jet reveal really hot hydrogen gas, the orange shows warm gas, and the reddish wisps at the end represent the coolest gas. 

The fact that gas toward the beginning of the jet is hotter than gas near the middle suggests that the stars must give off regular bursts of energy — and the material closest to the star is being heated by shockwaves from a recent stellar outburst. Meanwhile, the tints of orange reveal gas that is currently being heated by shockwaves from a previous stellar outburst. By the time these shockwaves reach the end of the jet, they have slowed down so significantly that the gas is only heated a little, and looks red.”

Exposure: 5 hrs 50 min RGB
Telescope: PlaneWave CDK20 0.5m f/6.8
Mount: PlaneWave Ascension A200h
Oag: Astrodon MonsterMOAG
Acquisition: ACP-8 Expert
Calibration: CCDStack v2
Observatory Site:, Siding Spring, NSW, Australia
Camera: SBIG STX16803
Filters: Astrodon E-Series RGB
Guider: SX Lodestar
Camera Operation: MaximDL 5.24
Processing: Photoshop CC 2018
Image Date: 04/18/2018 - 04/19/2018


  1. Josep Drudis

    An interesting target coupled to a masterful processing. Congratulations! It shows that amateur astrophotography is already quite advanced and can complement (help) the professional astronomers. Please, keep on showing us unusual objects!

  2. Sakib

    Ooh dark and ominous like a cosmic personification of something out of Shakespeare. I don’t know where you find these objects??? 🙂


Submit a Comment

Your email address will not be published. Required fields are marked *

The reCAPTCHA verification period has expired. Please reload the page.