NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft has been brought out of hibernation and has resumed surveying the sky at 3.4 and 4.6 um. The scientific objectives of the NEOWISE reactivation mission are to detect, track, and characterize near-Earth asteroids and comets. The search for minor planets resumed on December 23, 2013, and the first new near-Earth object (NEO) was discovered six days later. As an infrared survey, NEOWISE detects asteroids based on their thermal emission and is equally sensitive to high and low albedo objects; consequently, NEOWISE-discovered NEOs tend to be large and dark. Over the course of its three-year mission, NEOWISE will determine radiometrically-derived diameters and albedos for approximately 2000 NEOs and tens of thousands of Main Belt asteroids. The 32 months of hibernation have had no significant effect on the mission's performance. Image quality, sensitivity, photometric and astrometric accuracy, completeness, and the rate of minor planet detections are all essentially unchanged from the prime mission's post-cryogenic phase.
翻译:美国航天局的广域红外探测探测器航天器已经从休眠状态中分离出来,恢复对天空进行3.4和4.6微米的观测。近地天体红外探测系统的恢复飞行任务的科学目标是探测、跟踪和定性近地小行星和彗星。2013年12月23日恢复了对小行星的搜索,六天后又发现了第一个新的近地天体。作为红外测量,近地红外探测系统根据热排放探测小行星,对高低反照率物体同样敏感;因此,近地红外探测系统所发现的近地天体往往大而暗。近地红外探测系统在其三年任务期间,将确定大约2000个近地天体和数万个主要贝尔特小行星的辐射源直径和反照率。32个月的休眠对飞行任务的性能没有重大影响。图像质量、敏感度、光度和天体测量精度、完整性和小行星探测率都与飞行任务的后转阶段基本没有变化。