Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2509.05522

Six microlensing planets detected via sub-day signals during the 2023 -- 2024 season

Cheongho Han·Chung-Uk Lee·Andrzej Udalski·Ian A. Bond·Michael D. Albrow·Sun-Ju Chung·Andrew Gould·Youn Kil Jung·Kyu-Ha Hwang·Yoon-Hyun Ryu·Yossi Shvartzvald·In-Gu Shin·Jennifer C. Yee·Weicheng Zang·Hongjing Yang·Sang-Mok Cha·Doeon Kim·Dong-Jin Kim·Seung-Lee Kim·Dong-Joo Lee·Yongseok Lee·Byeong-Gon Park·Richard W. Pogge·Przemek Mróz·Michał K. Szymański·Jan Skowron·Radosław Poleski·Igor Soszyński·Paweł Pietrukowicz·Szymon Kozłowski·Krzysztof A. Rybicki·Patryk Iwanek·Krzysztof Ulaczyk·Marcin Wrona·Mariusz Gromadzki·Mateusz J. Mróz·Michał Jaroszyński·Marcin Kiraga·Fumio Abe·David P. Bennett·Aparna Bhattacharya·Akihiko Fukui·Ryusei Hamada·Stela Ishitani Silva·Yuki Hirao·Naoki Koshimoto·Yutaka Matsubara·Shota Miyazaki·Yasushi Muraki·Tutumi Nagai·Kansuke Nunota·Greg Olmschenk·Clément Ranc·Nicholas J. Rattenbury·Yuki Satoh·Takahiro Sumi·Daisuke Suzuki·Sean K. Terry·Paul J. Tristram·Aikaterini Vandorou·Hibiki Yama
View original source ↗Read source document ↗Export metadata ↓

Abstract

We present analyses of six microlensing events: KMT-2023-BLG-0548, KMT-2023-BLG-0830, KMT-2023-BLG-0949, KMT-2024-BLG-1281, KMT-2024-BLG-2059, and KMT-2024-BLG-2242. These were identified in KMTNet data from the 2023 -- 2024 seasons, selected for exhibiting anomalies shorter than one day -- potential signatures of low-mass planetary companions. Detailed modeling of the light curves reveals that the anomalies in all six events are caused by planetary companions to the lenses. The brief durations of the anomalies are attributed to various factors: a low planet-to-host mass ratio (KMT-2024-BLG-2059, KMT-2024-BLG-2242), a wide planet-host separation (KMT-2023-BLG-0548), small and elongated caustics restricting the source's interaction region (KMT-2023-BLG-0830, KMT-2024-BLG-1281), and a partial caustic crossing (KMT-2023-BLG-0949). { For KMT-2023-BLG-0548, the Bayesian posterior distribution of the lens mass shows two distinct peaks: a low-mass solution indicating a sub-Jovian planet orbiting an M dwarf in the Galactic disk, and a high-mass solution suggesting a super-Jovian planet around a K-type dwarf in the bulge. KMT-2023-BLG-0830 hosts a Neptune-mass planet orbiting an M dwarf in the Galactic bulge. KMT-2023-BLG-0949 involves a super-Jovian planet orbiting a $\sim 0.5~M_\odot$ host located at $\sim 6$ kpc. KMT-2024-BLG-2059Lb is a super-Earth with a mass about seven times that of Earth, orbiting an early M dwarf of $\sim 0.5~M_\odot$. KMT-2024-BLG-1281L hosts a planet slightly more massive than Neptune, orbiting an M dwarf of $\sim 0.3~M_\odot$. The short timescale and small angular Einstein radius of KMT-2024-BLG-2242 suggest a $\sim 0.07~M_\odot$ primary, likely a brown dwarf, with a Uranus/Neptune-mass planet.

Explore related subjects

astro-ph.EPastro-ph.GA

Keep this discovery

BibTeXRIS

Cheongho Han, Chung-Uk Lee, Andrzej Udalski, Ian A. Bond, Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Youn Kil Jung, Kyu-Ha Hwang, Yoon-Hyun Ryu, Yossi Shvartzvald, In-Gu Shin, Jennifer C. Yee, Weicheng Zang, Hongjing Yang, Sang-Mok Cha, Doeon Kim, Dong-Jin Kim, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radosław Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof A. Rybicki, Patryk Iwanek, Krzysztof Ulaczyk, Marcin Wrona, Mariusz Gromadzki, Mateusz J. Mróz, Michał Jaroszyński, Marcin Kiraga, Fumio Abe, David P. Bennett, Aparna Bhattacharya, Akihiko Fukui, Ryusei Hamada, Stela Ishitani Silva, Yuki Hirao, Naoki Koshimoto, Yutaka Matsubara, Shota Miyazaki, Yasushi Muraki, Tutumi Nagai, Kansuke Nunota, Greg Olmschenk, Clément Ranc, Nicholas J. Rattenbury, Yuki Satoh, Takahiro Sumi, Daisuke Suzuki, Sean K. Terry, Paul J. Tristram, Aikaterini Vandorou, Hibiki Yama. 2025-09-05. Six microlensing planets detected via sub-day signals during the 2023 -- 2024 season. https://arxiv.org/abs/2509.05522

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Planetary Accretion Is Less Frequent in Wide Binaries: Evidence from Metal-Enriched White Dwarfs in DESI DR1

Binary stars are common in the Galaxy, and understanding how stellar binarity influences the formation and evolution of planetary systems is an active area of research. In this study, we use metal-enriched white dwarfs in wide binaries as tracers of long-lived planetary systems. With Data Release 1 from the Dark Energy Spectroscopic Instrument (DESI), we find that the fraction of cool metal-enriched white dwarfs in wide binaries is 9.8\,$\pm$\,2.1\%, significantly lower (4.7\,$\sigma$) than the 20.5\,$\pm$\,0.9\% in a control sample of single systems. Furthermore, we identify a tentative dependence of metal enrichment on projected separation and white dwarf effective temperature, where enrichment fraction decreases at smaller separations and lower temperatures. These findings indicate that, compared to single stars, binary systems either start with smaller initial planetary reservoirs due to suppressed planetesimal formation or undergo more rapid depletion of planetary material during the initial part of the white dwarf stage.

astro-ph.EP↗
arXiv2026

The Mysterious Inspiral of WASP-12b: Why Obliquity Tides Cannot Drive Orbital Decay

WASP-12b's orbit is decaying, for unknown reasons. The planet's period is shrinking more rapidly than can be attributed to equilibrium tides or dynamical tides in a main-sequence star. Planetary obliquity tides could be sufficiently dissipative to drive WASP-12b's inspiral, but would also damp the planet's obliquity, halting the decay. Millholland & Laughlin proposed that a nearby, low-mass planet ($\sim 10$ M$_\oplus$) is maintaining a large obliquity for WASP-12b, sustaining the dissipation. We re-evaluated this hypothesis, finding that the companion must be more massive than originally proposed ($\gtrsim 65$ M$_\oplus$) to absorb WASP-12b's orbital angular momentum. Radial velocity data allowed us to rule out a companion of this type. Any companions within $3$ AU have $K \lesssim 14$ m/s at $95$% confidence.

astro-ph.EP↗
arXiv2026

Lava Tube Exploration with LunarLeaper

Lunar pits, some of which are interpreted as collapse features into underlying lava tubes, expose otherwise inaccessible stratigraphy and may provide entry points to subsurface voids that preserve records of lunar volcanism and offer potential sites for future human exploration. We synthesize the current state of knowledge on lunar pits and lava tubes, covering their morphological characteristics, classification, proposed formation mechanisms, mechanical stability, and detection from orbit. We then review the open science questions that pit and pit-wall investigation is uniquely placed to address, spanning the volcanic stratigraphy of the lunar maria, the structure and lateral variability of the regolith, and the dimensions and accessibility of subsurface conduits. To evaluate how these questions can be tackled in situ, we assess the feasibility and expected performance of geophysical and remote-sensing investigations for subsurface voids and surface exposures, mainly focusing on gravity measurements, ground-penetrating radar, high-resolution imaging, and spectroscopy. Building on this, we present LunarLeaper, a small legged robot mission concept combining a gravimeter, ground-penetrating radar, high-resolution imager, spectrometer, and leg-based geomechanical experiments to deliver the first in situ investigation of a mare pit. The concept targets the Marius Hills Pit and its associated rille, with a mobility architecture optimized for the rugged terrain encountered at pit edges and funnel slopes.

astro-ph.EP↗