Previously Unknown Galactic Real Estate

[Recusant]

Still some surprises in store. Peeking through the clouds of dust with fancy equipment! Is it there, or is it (metaphorically) a smudge on the lens? 

"Astronomers Detected a Huge New Structure in The Milky Way, And Don't Know What It Is" | Science Alert

When you're swimming in a large body of water, calculating its volume or discerning the locations of distant floating objects isn't easy. The same is true for our galaxy.

From our position inside the Milky Way, much of its size, contents, and three-dimensional structure is really tricky to figure out. There's a lot that eludes us, or is impossible to calculate; even so, every now and again, a discovery comes along that makes you wonder, how in the heck did we miss that?!

A newly discovered structure named the Cattail is just such a wonder. It's a long curl of gas that's so large, astronomers aren't sure whether or not it might actually be part of a galactic spiral arm that we never noticed until now.

Even if it isn't the sign of an unmapped spiral arm, the Cattail may be the largest filament of gas in our galaxy discovered to date. It's been described in a paper accepted to The Astrophysical Journal Letters, available on preprint server arXiv.

The structure "appears to be so far the furthest and largest giant filament in the galaxy," a team of astronomers from Nanjing University in China writes in the paper.

"The question about how such a huge filament is produced at the extreme galactic location remains open. Alternatively, Cattail might be part of a new arm ... though it is puzzling that the structure does not fully follow the warp of the galactic disk."

[Continues . . .]

There's a link to the preprint version of the paper in the article, but here it is again:

"The discovery of the largest gas filament in our Galaxy, or a new spiral arm?" | arXiv

[Tank]

Good article!