ApJL: New stars being formed at our galaxy's edge

[MargaritaMc]

There is evidence in this paper Recent Star Formation in the Leading Arm of the Magellanic Stream by
Dana I. Casetti-Dinescu, Christian Moni Bidin, et al.
for star creation caused by the interaction of the Milky Way Galaxy and the Magellanic Clouds.

This is an article about the findings by Ken Croswell in the Scientific American
Star Birth Sparked at the Galaxy's Edge

Especially intriguing is the find of a spectral class O6 star which must have been born in the galactic halo.

Margarita

[MargaritaMc]

This paper is discussed in today's astrobite.
http://astrobites.org/2014/04/14/formin ... he-stream/ which has this, to me, helpful image of the Magellanic Stream and Clouds

Click to view full size image

Shown here is a composite image of our Milky Way (optical, center) and the large stream of gas associated with the Magellanic Clouds (radio, red). The Small and Large Magellanic clouds can be seen as the small and large bright spots towards the lower right, connected to each other by a bridge of gas. Behind these galaxies is a long tail known as the Magellanic Stream. Ahead is the branched, leading arm. (Credit: Nidever, et. al., NRAO/AUI/NSF and Meilinger, Leiden-Argentine-Bonn Survey, Parkes Observatory, Westerbork Observatory, Arecibo Observitory)


Regarding the O6V class star found in the Stream

Andrew Emerick writes that it
has a temperature of 43,700 K, and a mass around 40 solar masses. This is a far younger, and far hotter star from anything else in the sample. At this temperature and mass, this star has a lifetime on the order of 1-2 millions of years. Given this very short lifetime, the authors rule out the possibility that this star came from the Milky Way (it would have to be at least 385 millions years old if it did). In addition, they rule out the possibility that it came from the Large Magellanic Cloud, as it would have to have an unrealistically large velocity to move from the Large Magellanic Cloud to where it is currently located.

Because of this, the authors conclude that they have just discovered for the first time a star that formed very recently within the leading arm of the Magellanic stream. This young, hot star was born out of the interactions between the Milky Way galaxy and the two Magellanic Clouds, but exits completely independent of them

Margarita

[bystander]

There is evidence in this paper Recent Star Formation in the Leading Arm of the Magellanic Stream by
Dana I. Casetti-Dinescu, Christian Moni Bidin, et al.
for star creation caused by the interaction of the Milky Way Galaxy and the Magellanic Clouds.

Recent Star Formation in the Leading Arm of the Magellanic Stream - Dana I. Casetti-Dinescu et al

• Astrophysical Journal Letters 784(2) L37 (2014 Apr 01) DOI: 10.1088/2041-8205/784/2/L37
  arXiv.org > astro-ph > arXiv:1403.0517 > 03 Mar 2014

[MargaritaMc]

Thanks for posting the arXiv link, bystander. I downloaded it for myself and totally forgot that it wasn't posted here!
M