We use microlensing to probe the inner broad line region (BLR) of the lensed quasar SDSS J1004+4112, finding evidence of substructure. We study the recurrent microlensing events observed in the blue wing of the C IV emission line in image A of this lensed quasar from a series of 20 spectra taken over 15 yr. We obtain a microlensing light curve and

This study is part of an ongoing project in which we experimentally examine the effect of composition (refractive index) and surface roughness on the scattering matrix elements of a set of well-characterized rough regolith simulants. A set of four cylindrical Mars regolith simulants with controlled degrees of porosity and surface roughness is

Dusty disks around planetary and substellar companions in outer reaches of exoplanetary systems can be detected as long-lasting occultations, provided the observer is close to the secondary's orbital plane. Here we report optical spectroscopy with KOSMOS (Apache Point Observatory), MagE (Magellan), and GHOST (Gemini-S) of ASASSN-24fw (Gaia 07:05:18

As the intermediate-mass siblings of stars and planets, brown dwarfs (BDs) are vital to study for a better understanding of how objects change across the planet-to-star mass range. Here, we report two low-mass transiting BD systems discovered by TESS, TOI-4776 (TIC 196286578) and TOI-5422 (TI 80611440), located in an underpopulated region of the BD

We present observations and analyses of three high-magnification microlensing events: KMT-2022-BLG-0954, KMT-2024-BLG-0697, and MOA-2024-BLG-018. All three exhibit the 'Planet/Binary' degeneracy, with planetary solutions corresponding to mass ratios in the range $-3.7 < \log q < -2.2$, while the binary solutions yield $\log q > -2.0$. For KMT-2022

We present observations and analyses of three high-magnification microlensing events: KMT-2022-BLG-0954, KMT-2024-BLG-0697, and MOA-2024-BLG-018. All three exhibit the 'Planet/Binary' degeneracy, with planetary solutions corresponding to mass ratios in the range $-3.7 < \log q < -2.2$, while the binary solutions yield $\log q > -2.0$. For KMT-2022