APOD: Chamaeleon II Dark Cloud (2019 Aug 02)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 4737
Joined: Fri Dec 04, 2009 3:27 am

APOD: Chamaeleon II Dark Cloud (2019 Aug 02)

Post by APOD Robot » Fri Aug 02, 2019 4:05 am

Image Chamaeleon II Dark Cloud

Explanation: A small constellation hiding near the south celestial pole, The Chamaeleon boasts no bright stars. Stars are forming within its constellation boundaries though, in a complex of dark, dusty molecular clouds. Some 500 light-years distant, the Chamaeleon II dark nebula inhabits this view where the cosmic dust clouds standout mostly in silhouette against the starry southern sky. The telescopic frame is about the angular size of a Full Moon and so spans about 5 light-years at the dark cloud's estimated distance. Scattered near center a telltale reddish glow from identified Herbig-Haro objects is seen in the sharp image, jets of shocked glowing gas emanating from recently formed stars.

<< Previous APOD This Day in APOD Next APOD >>

User avatar
4725 Å
Posts: 12182
Joined: Sat May 29, 2010 5:33 am

Re: APOD: Chamaeleon II Dark Cloud (2019 Aug 02)

Post by Ann » Fri Aug 02, 2019 5:18 am

Chamaeleon II Dark Cloud.png
Low mass star formation in Chamaeleon II Dark Cloud.
Photo: Don Goldman.
High mass star formation in the Statue of Liberty Nebula.
Photo: Andrew Campbell.

Together with the APOD of July 30, 2019, today's APOD is a perfect illustration of the difference between high-mass and low-mass star formation. Not only are high-mass and low-mass stars very different during their lifetimes, but their birth cries are very different, too.

You can tell from the appearance of Chamaeleon II Dark Cloud that no high-mass stars are being born there. Wikipedia mentions 40 X-ray sources in Chamaeleon II Dark Cloud, and just one star, of spectral class K1. So it is possible and even probable that all the stars forming in Chamaeleon Dark Cloud are smaller and less massive than the Sun.

You do not have the required permissions to view the files attached to this post.
Color Commentator

User avatar
orin stepanek
Posts: 7671
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Re: APOD: Chamaeleon II Dark Cloud (2019 Aug 02)

Post by orin stepanek » Fri Aug 02, 2019 11:19 am

Did you ever walk at night when it was so dark; that only the street lights allowed you to navigate? That's what these dark clouds remind me of!

Smile today; tomorrow's another day!

Stellar Cartographer
Posts: 4833
Joined: Thu Mar 15, 2012 7:25 pm

Re: APOD: Chamaeleon II Dark Cloud (2019 Aug 02)

Post by starsurfer » Fri Aug 02, 2019 1:31 pm

You can see the whole Chamaeleon II complex in this widefield image by the Atacama Photographic Observatory.