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JWST Imaging of Earendel, the Extremely Magnified Star at Redshift z = 6.2
Ouchi, Masami; Hutchison, Taylor A.; Larson, Rebecca L. +60 more
The gravitationally lensed star WHL 0137-LS, nicknamed Earendel, was identified with a photometric redshift z phot = 6.2 ± 0.1 based on images taken with the Hubble Space Telescope. Here we present James Webb Space Telescope (JWST) Near Infrared Camera images of Earendel in eight filters spanning 0.8-5.0 µm. In these higher-resolu…
The Coma Cluster at LOFAR Frequencies. II. The Halo, Relic, and a New Accretion Relic
Simionescu, A.; Zhang, X.; Brunetti, G. +26 more
We present LOw Frequency ARray observations of the Coma Cluster field at 144 MHz. The cluster hosts one of the most famous radio halos, a relic, and a low surface brightness bridge. We detect new features that allow us to make a step forward in the understanding of particle acceleration in clusters. The radio halo extends for more than 2 Mpc, whic…
Milky Way's Eccentric Constituents with Gaia, APOGEE, and GALAH
Caldwell, Nelson; Myeong, G. C.; Belokurov, Vasily +3 more
We report the results of an unsupervised decomposition of the local stellar halo in the chemodynamical space spanned by the abundance measurements from APOGEE DR17 and GALAH DR3. In our Gaussian mixture model, only four independent components dominate the halo in the solar neighborhood, three previously known, Aurora, Splash, and Gaia-Sausage/Ence…
The X-Ray Polarization View of Mrk 421 in an Average Flux State as Observed by the Imaging X-Ray Polarimetry Explorer
Wu, Kinwah; Enoto, Teruaki; Turolla, Roberto +100 more
Particle acceleration mechanisms in supermassive black hole jets, such as shock acceleration, magnetic reconnection, and turbulence, are expected to have observable signatures in the multiwavelength polarization properties of blazars. The recent launch of the Imaging X-Ray Polarimetry Explorer (IXPE) enables us, for the first time, to use polariza…
The Star Formation Rate of the Milky Way as Seen by Herschel
Martin, P. G.; Paladini, R.; Klessen, R. S. +23 more
We present a new derivation of the Milky Way's current star formation rate (SFR) based on the data of the Herschel InfraRed Galactic Plane Survey (Hi-GAL). We estimate the distribution of the SFR across the Galactic plane from the star-forming clumps identified in the Hi-GAL survey and calculate the total SFR from the sum of their contributions. T…
The Hubble Tension Revisited: Additional Local Distance Ladder Uncertainties
Dhawan, Suhail; Goobar, Ariel; Mörtsell, Edvard +1 more
In a recent paper, we investigated possible systematic uncertainties related to the Cepheid color-luminosity calibration method and their influence on the tension between the Hubble constant as inferred from distances to Type Ia supernovae and the cosmic microwave background as measured with the Planck satellite. Here, we study the impact of other…
Unscrambling the Lensed Galaxies in JWST Images behind SMACS 0723
Wilkins, Stephen M.; Broadhurst, Tom; Frye, Brenda L. +16 more
The first deep field images from the James Webb Space Telescope (JWST) of the galaxy cluster SMACS J0723.3-7327 reveal a wealth of new lensed images at uncharted infrared wavelengths, with unprecedented depth and resolution. Here we securely identify 14 new sets of multiply imaged galaxies totaling 42 images, adding to the five sets of bright and …
Varstrometry for Off-nucleus and Dual Subkiloparsec AGN (VODKA): Hubble Space Telescope Discovers Double Quasars
Shen, Yue; Zakamska, Nadia L.; Chen, Yu-Ching +4 more
Dual supermassive black holes (SMBHs) at ~kiloparsec scales are the progenitor population of SMBH mergers and play an important role in understanding the pairing and dynamical evolution of massive black holes in galaxy mergers. Because of the stringent resolution requirement and the apparent rareness of these small-separation pairs, there are scar…
Let the Great World Spin: Revealing the Stormy, Turbulent Nature of Young Giant Exoplanet Analogs with the Spitzer Space Telescope
Metchev, Stanimir; Marley, Mark; Faherty, Jacqueline K. +5 more
We present a survey for photometric variability in young, low-mass brown dwarfs with the Spitzer Space Telescope. The 23 objects in our sample show robust signatures of youth and share properties with directly imaged exoplanets. We present three new young objects: 2MASS J03492367+0635078, 2MASS J09512690-8023553, and 2MASS J07180871-6415310. We de…
No Such Thing as a Simple Flare: Substructure and Quasi-periodic Pulsations Observed in a Statistical Sample of 20 s Cadence TESS Flares
MacGregor, Meredith A.; Howard, Ward S.
A 20 s cadence Transiting Exoplanet Survey Satellite monitoring campaign of 226 low-mass flare stars during Cycle 3 recorded 3792 stellar flares of ≥1032 erg. We explore the time-resolved emission and substructure in 440 of the largest flares observed at high signal-to-noise, 97% of which released energies of ≥1033 erg. We di…