Abstract We present a near-infrared (NIR) candidate star cluster catalog for the central kiloparsec of M82 based on new JWST NIRCam images. We identify star cluster candidates using the F250M filter, finding 1357 star cluster candidates with stellar masses >104M⊙. Compared to previous optical catalogs, nearly all (87%) of the candidates we identify are new. The star cluster candidates have a median intrinsic cluster radius of ≈1 pc and stellar masses up to 106M⊙. By comparing the color–color diagram to dust-freeyggdrasilstellar population models, we estimate that the star cluster candidates haveAV∼ 3−24 mag, corresponding toA2.5μm∼ 0.3−2.1 mag. There is still appreciable dust extinction toward these clusters into the NIR. We measure the stellar masses of the star cluster candidates, assuming ages of 0 and 8 Myr. The slope of the resulting cluster mass function isβ= 1.9 ± 0.2, in excellent agreement with studies of star clusters in other galaxies.
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This content will become publicly available on September 1, 2026
Crowdsourcing star-formation research and the power of participatory science
Abstract We review participatory science programs that have contributed to the understanding of star formation. The Milky Way Project (MWP), one of the earliest participatory science projects launched on the Zooniverse platform, produced the largest catalog of “bubbles” associated with feedback from hot young stars to date, and enabled the identification of a new class of compact star-forming regions (SFRs) known as “yellowballs” (YBs). The analysis of YBs through their infrared colors and catalog cross-matching led to discovering that YBs are compact photodissociation regions generated by intermediate- and high-mass young stellar objects embedded in clumps that range in mass from 10 - 104M⊙and luminosity from 10 - 106L⊙. The MIRION catalog, assembled from 6176 YBs identified by citizen scientists, increases the number of candidate intermediate-mass SFRs by nearly two orders of magnitude. Ongoing work utilizing data from theSpitzer,HerschelandWISEmissions involves analyzing infrared color trends to predict physical properties and ages of YB environments. Methods include applying summary statistics to histograms and color-color plots as well as SED fitting. Students in introductory astronomy classes contribute toward continued efforts refining photometric measurements of YBs while learning fundamental concepts in astronomy through a classroom-based participatory science experience, the PERYSCOPE project. We also describe an initiative that engaged seminaries, family groups, and interfaith communities in a wide variety of science projects on the Zooniverse platform. This initiative produced important guidance on attracting audiences that are underserved, underrepresented, or apprehensive about science.
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- Award ID(s):
- 2307806
- PAR ID:
- 10635509
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Astrophysics and Space Science
- Volume:
- 370
- Issue:
- 9
- ISSN:
- 0004-640X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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