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is a small asteroid that is a Near-Earth object and an Aten asteroid. ==Orbit== was discovered February 17, 1993 by the Kitt Peak Spacewatch. From 1993 to 1998, was the asteroid with the lowest known aphelion at 1.023 AU, and was thus the closest thing to an Apohele asteroid known at the time. When was discovered February 23, 1998, it was found to have an aphelion less than , and also less than the Earth's distance to the Sun (0.980 ± 0.05 AU), making it the first detected Apohele asteroid. However, was lost before the orbit could be confirmed, so retained the title of the asteroid with the lowest known aphelion. When was discovered November 25, 1998, it was found to have a slightly smaller aphelion (1.019 AU) than , so took the title. However, lost its smallest aphelion title almost immediately when (aphelion of 1.014 AU) was discovered only a few weeks later on December 8, 1998. The orbit of brings it during the years 1900–2200 as close as of the Earth (on Feb 19, 1993) and as close as of Venus (on October 15, 1933, and Sept 30, 2077).〔(【引用サイトリンク】url=http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=1993%20DA;cad=1#cad )〕 For comparison, the distance to the Moon is about 0.0026 AU (384,400 km). Because the orbit was determined with only 5 days worth of observations, the orbit of has a uncertainty of 6 on a scale of 0 to 9, with 0 being the most certain, and 9 being the most uncertain. This uncertainty is common for small asteroids that are difficult to observe. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「1993 DA」の詳細全文を読む スポンサード リンク
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