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Disks in Nearby Young Stellar Associations Found Via Virtual Reality
Debes, John H.; Kuchner, Marc J.; Gagné, Jonathan +25 more
The Disk Detective citizen science project recently released a new catalog of disk candidates found by visual inspection of images from NASA's Wide-field Infrared Survey Explorer mission and other surveys. We applied this new catalog of well-vetted disk candidates to search for new members of nearby young stellar associations (YSAs) using a novel …
Light Deflection under the Gravitational Field of Jupiter-Testing General Relativity
Xu, Ye; Hao, Chaojie; Li, Yingjie +6 more
We measured the relative positions between two pairs of compact extragalactic sources (CESs), J1925-2219 and J1923-2104 (C1-C2) and J1925-2219 and J1928-2035 (C1-C3), on 2020 October 23-25 and 2021 February 5 (totaling four epochs), respectively, using the Very Long Baseline Array at 15 GHz. Accounting for the deflection angle dominated by Jupiter…
Mass and Age Determination of the LAMOST Data with Different Machine-learning Methods
Ting, Yuan-Sen; Deng, Li-Cai; Wang, Hai-Feng +3 more
We present a catalog of 948,216 stars with mass labels and a catalog of 163,105 red clump (RC) stars with mass and age labels simultaneously. The training data set is crossmatched from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope DR5, and high-resolution asteroseismology data, mass, and age are predicted by the random forest (RF) …
Milliarcsecond Astrometry for the Galilean Moons Using Stellar Occultations
Aoki, S.; Smith, M.; Carlson, R. W. +40 more
A stellar occultation occurs when a Solar System object passes in front of a star for an observer. This technique allows the sizes and shapes of the occulting body to be determined with kilometer precision. In addition, this technique constrains the occulting body's positions, albedos, densities, and so on. In the context of the Galilean moons, th…
Quantifying the cool ISM in radio AGNs: evidence for late-time retriggering by galaxy mergers and interactions
Daddi, E.; Morganti, R.; Tadhunter, C. N. +5 more
We use deep Herschel observations of the complete 2Jy sample of powerful radio active galactic nuclei (AGNs) in the local Universe (0.05 < z < 0.7) to probe their cool interstellar medium (ISM) contents and star-forming properties, comparing them against other samples of nearby luminous AGNs and quiescent galaxies. This allows us to investig…
Kepler and TESS Observations of PG 1159-035
Oliveira da Rosa, Gabriela; Kepler, S. O.; Córsico, Alejandro H. +11 more
PG 1159-035 is the prototype of the PG 1159 hot (pre-)white dwarf pulsators. This important object was observed during the Kepler satellite K2 mission for 69 days in 59 s cadence mode and by the TESS satellite for 25 days in 20 s cadence mode. We present a detailed asteroseismic analysis of those data. We identify a total of 107 frequencies repres…
Using 3D and 2D analysis for analyzing large-scale asymmetry in galaxy spin directions
Shamir, Lior
The nature of galaxy spin is still not fully known. Iye, Yagi, and Fukumoto (2021, AJ, 907, 123) applied a 3D analysis to a dataset of bright SDSS galaxies that was used in the past for photometric analysis. They showed that the distribution of spin directions of spiral galaxies is random, providing a dipole axis with low statistical significance …
Accretion Variability of the Multiple T Tauri System VW Cha
Pál, András; Ábrahám, Péter; Kóspál, Ágnes +5 more
Classical T Tauri stars are low-mass objects that are still accreting material from the surrounding circumstellar disk. The accretion process is essential in the formation of Sun-like stars and in setting the properties of the disk at the time when planet formation occurs. We constructed a complex data set in order to examine the accretion process…
Presence of clay minerals can obscure spectral evidence of Mg sulfates: implications for orbital observations of Mars
Milliken, Ralph E.; Sheppard, Rachel Y.; Robertson, Kevin M.
The martian crust is often viewed through the lens of its dominant secondary minerals, Noachian phyllosilicates and Hesperian sulfates, based on orbital spectral observations. However, the effects of surface exposure on the spectra of these hydrous minerals are not fully understood. We use an environmental chamber to measure changes in near-infrar…
Prospects for mapping temporal height variations of the seasonal CO2 snow/ice caps at the Martian poles by co-registration of MOLA profiles
Oberst, Jürgen; Schmidt, Frédéric; Steinbrügge, Gregor +3 more
We investigate the feasibility and demonstrate the merits of using Mars Orbiter Laser Altimeter (MOLA) profiles to retrieve seasonal height variations of CO2 snow/ice cap in Mars' polar areas by applying a co-registration strategy. We present a prototype analysis on the research region of [85.75°S, 86.25°S, 300°E, 330°E] that is located…