AI 中文总结
本研究结合多设备观测数据，确定潜在危险小行星2001 WN₅的自转、光谱类型等参数，为其2028年近距离接近的观测做准备。
AI 中文摘要
潜在危险小行星(153814)2001 WN₅将于2028年6月26日在月球距离以内飞过，这为高角分辨率表征一颗千米级近地小行星提供了罕见机会。我们旨在约束2001 WN₅在2028年近距离接近前的自转状态、形状、可见光颜色、几何反照率及分类。我们结合了1.54m丹麦望远镜(DK154)的新测光数据，以及来自凌日系外行星巡天卫星(TESS)、暗能量相机(DECam)、兹威基瞬变巡天装置(ZTF)和小行星撞击最后警报系统(ATLAS)的存档与巡天观测数据。这些数据用于修正自转周期、研究自旋-形状解空间、推导可见光颜色，并通过相位曲线斜率估算几何反照率。现有光变曲线无法唯一确定恒星自转周期，但最优极解位于黄道坐标的南半球。多个独立数据集的可见光颜色与C型复合体一致，而TESS相位曲线斜率给出p_V=0.13±0.04，与此前热红外反照率估计值相符。结合可见光颜色、反照率及已发表的近红外光谱，我们将2001 WN₅归类为最可能的B型小行星。利用H-G模型估算的有效直径为D=0.81±0.13km，而线性模型得出的数值略小，为0.74±0.11km。在2028年相遇期间，2001 WN₅的视直径应达到约0.5角秒，使其成为测光、光谱及高角分辨率协同观测的极佳目标。2026-2027年冲期的观测对于完善其2028年近距离接近前的自旋与形状模型至关重要。
英文摘要
The potentially hazardous asteroid (153814) 2001 WN$_5$ will pass inside the lunar distance on June 26, 2028, offering a rare opportunity to characterize a kilometer-scale near-Earth asteroid at high angular resolution. We aim to constrain the rotation state, shape, visible colors, geometric albedo, and taxonomy of 2001 WN$_5$ before its 2028 close approach. We combined new photometry from the 1.54 m Danish Telescope (DK154) with archival and survey observations from the Transiting Exoplanet Survey Satellite (TESS), Dark Energy Camera (DECam), Zwicky Transient Facility (ZTF), and the Asteroid Terrestrial-impact Last Alert System (ATLAS). These data were used to refine the rotation period, investigate the spin-shape solution space, derive visible colors, and estimate the geometric albedo from phase curve slopes. The available lightcurves do not uniquely constrain the sidereal rotation period, but the preferred pole solutions lie in the southern hemisphere in ecliptic coordinates. Visible colors from multiple independent datasets are consistent with the C-complex, while the TESS phase curve slopes give $p_{\rm V} = 0.13\pm0.04$, consistent with previous thermal-infrared albedo estimates. Combining the visible colors, albedo, and published near-infrared spectra, we classify 2001 WN$_5$ as most likely a B-type asteroid. The effective diameter is estimated to be $D = 0.81 \pm 0.13$ km using the $H$-$G$ model, while the linear model yields a slightly smaller value of $0.74 \pm 0.11$ km. During the 2028 encounter, 2001 WN$_5$ should reach an apparent diameter of about 0.5~arcsec, making it an excellent target for coordinated photometric, spectroscopic, and high-angular-resolution observations. Observations during the 2026-2027 apparition will be essential for improving its spin and shape model before its 2028 close approach.
CommentsAccepted for publication in Astronomy & Astrophysics (A&A). Abstract shortened for arXiv. Any comments are welcome
