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Cloud Dreaming in Outerspace
Barnard 33 or the HorseheadLook out! The giant ice cream cone is about to collide with the turtle! We’ve all imagined clouds in fantastical shapes, but did you know that cool cloud images are formed in space as well?

We’re looking at Barnard 33. Astronomers call it the Horsehead. Discovered in the 1800s, this nebula is located some 1,600 light years away from Earth in the constellation Orion, just south of the left-most star, Zeta Orionis, in Orion’s belt. The Horsehead is a dark nebula in front of the pink active star-forming emission nebula, IC 434.

So what exactly is this strange, dark stallion? Simply put it is a cocoon-like cluster of young stars. The nebula is a dark, dense cloud of gas and dust, obscuring the bright light coming from behind it. The streaks that extend above the Horsehead are probably due to magnetic fields within the nebula. A dark cloud of hydrogen gas is hiding stars in the lower half of the image.

Astronomers believe radiation erosion is the cause for this nebula’s unusual shape. Notice the bright glow at the top left edge? That’s a young star in a nursery of gas and dust. Far from lounging away in its crib, this hot star is emitting radiation and eroding the stellar nursery.

In a matter of minutes, the cloud images in our atmosphere shift and change. For the Horsehead, that inevitable change will take many thousands of years. In the meantime, sit back, stare up, and enjoy the night sky’s playground for the imagination.

Image Courtesy of T.A. Rector (NOAO/AURA/NSF) and Hubble Heritage Team (STScI/AURA/NASA)

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