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This content will become publicly available on March 26, 2026

Title: Searching for star formation towards the Eos molecular cloud
ABSTRACT The Eos cloud, recently discovered in the far ultraviolet via H$$_2$$ fluorescence, is one of the nearest known dark molecular clouds to the Sun, with a distance spanning from $${\sim} 94\rm{\!-\!}136$$ pc. However, with a mass ($${\sim} 5.5\times 10^3$$ M$$_\odot$$) just under $$40\,$$ per cent that of star forming clouds like Taurus and evidence for net molecular dissociation, its evolutionary and star forming status is uncertain. We use Gaia data to investigate whether there is evidence for a young stellar population that may have formed from the Eos cloud. Comparing isochrones and pre-main sequence evolutionary models there is no clear young stellar population in the region. While there are a small number of $${<} 10$$ Myr stars, that population is statistically indistinguishable from those in similar search volumes at other Galactic latitudes. We also find no unusual spatial or kinematic clustering toward the Eos cloud over distances $$70\!-\!150$$ pc. Overall, we conclude that the Eos cloud has most likely not undergone any recent substantial star formation and further study of the dynamics of the cloud is required to determine whether it will do so in the future.  more » « less
Award ID(s):
2407877
PAR ID:
10607917
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
MNRAS
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society: Letters
Volume:
540
Issue:
1
ISSN:
1745-3925
Page Range / eLocation ID:
L109 to L114
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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