Hubble's festive view of a grand star forming region

[orin stepanek]

http://hubblesite.org/newscenter/archiv ... es/2009/32
another beautiful view by Hubble! The blue stars are seen through an opening in the dust clouds make a wondrous sight. Zoom-able too.

[harry]

G'day orin

That image looks like a Vincent painting. Fantastic

I will do a painting of it and sell it for a million dollars.

Or the nearest dollar.

[rstevenson]

In the description of that image they say...

The brilliant stars are carving deep cavities in the surrounding material by unleashing a torrent of ultraviolet light, and hurricane-force stellar winds (streams of charged particles), which are etching away the enveloping hydrogen gas cloud in which the stars were born.

The word "etching" bothers me, since it suggests that the hydrogen is being obliterated in some sense. Surely it is simply being pushed aside? Or is there some chemical process going on there that would justify the term "etching"?

Rob

[Chris Peterson]

The word "etching" bothers me, since it suggests that the hydrogen is being obliterated in some sense. Surely it is simply being pushed aside? Or is there some chemical process going on there that would justify the term "etching"?

The hydrogen is indeed just being blown, not altered. My reaction to the word choice is different than yours; the word in this context doesn't make me think of etching in a chemical sense, but in its more mechanical sense, like waves on the beach etching a pattern in the sand. This seems especially so given the use of "carving" at the beginning of the same sentence.

[rstevenson]

Yes, makes sense now. I haven't been to the beach lately.

Rob