On the impact of the Yarkovsky effect on Apophis’ orbit
On the impact of the Yarkovsky effect on Apophis’ orbit
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论雅可夫斯基效应对阿波菲斯轨道的影响
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
N. B. Zheleznov
中科院分区：
文献类型：
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作者：
V. Shor;Yulija A. Chernetenko;O. M. Kochetova;N. B. Zheleznov
2009年10月，对阿波菲斯（一颗潜在危险的小行星）的一组新的光学观测结果发表了。这些数据大大扩大了观测的间隔和观测的总数。在本文中，我们比较了美国喷气推进实验室（JPL）、比萨大学（意大利）和俄罗斯科学院应用天文学研究所（IAA）对阿波菲斯轨道的改进结果，并考虑了新的观测结果。新的轨道将大大降低阿波菲斯在2036年与地球相撞的可能性。由于处理了大量接近地球的小行星和直径小于40公里的主带小行星的观测结果，并在不同的冲日点进行了大量的光学观测，在许多情况下还进行了雷达观测，其中一位作者揭示了额外的加速度会影响它们的运动。这个加速度可以用轨道坐标系中的横截分量A2来表示。这种加速度的存在可以解释为亚尔科夫斯基效应。小行星A2分布的统计特性，它被相当可靠地确定，支持这种解释的证据。对于阿波菲斯这样大小的天体，额外加速度的值在±10 - 13天文单位/天的范围内。在本文中，我们计算了在附加加速度A2的不同横向分量值下，阿波菲斯在2036年与地球相撞的概率。对于结果点，构造了与A2值碰撞的概率图。在A2 =−8.748 × 10−14 AU/day2（以及径向A1和法向A3分量的零值），2029年4月13日阿波菲斯轨道的公称解距离600米宽的“锁眼”中间只有90米，这将导致阿波菲斯在2036年与地球相撞。由于2029年目标平面上的散射椭圆与钥匙孔明显重叠，在给定的附加加速度值下，碰撞概率为0.0022。用蒙特卡罗方法验证了这一结果。考虑到它们之间的相关性，对10000组随机轨道元素进行了测试，结果表明，在2036年，有22个案例导致了虚拟小行星与地球的碰撞。构造了碰撞概率与A2值的关系图。
In October 2009, a new set of optical observations of Apophis, a potentially hazardous asteroid, was published. These data have significantly expanded the interval of observations and their total number. In the article we compare the results of refinement of Apophis’ orbit made at the Jet Propulsion Laboratory (JPL, United States), the University of Pisa (Italy), and the Institute of Applied Astronomy (IAA) of the Russian Academy of Sciences with consideration for new observations. New orbits lead to a significant decrease in the probability of Apophis’ collision with the Earth in 2036. As a result of processing a large number of observations of asteroids approaching the Earth and main belt asteroids less than 40 km in size, with a large number of optical and, in many cases, radar observations in different oppositions, one of the authors revealed that additional acceleration affects their motion. This acceleration can be represented by the transversal component A2 in the orbital coordinate system. The presence of this acceleration can be interpreted as the Yarkovsky effect. The statistical properties of distribution of A2 for asteroids, for which it is determined quite reliably, evidence in favor of this interpretation. The value of additional acceleration for bodies the size of Apophis falls in the range ±10−13 AU/day2. In this paper we have calculated the probability of Apophis colliding with the Earth in 2036 at different values of the transversal component of additional acceleration A2. For the resulting points, a plot of the probability of the collision against the A2 value has been constructed. At A2 = −8.748 × 10−14 AU/day2 (and zero values of the radial A1 and normal A3 components) the nominal solution for Apophis’ orbit on April 13, 2029, is only 90 m from the middle of a “keyhole” 600 m in width, which leads to a collision of Apophis with the Earth in 2036. Since the scattering ellipse in the target plane in 2029 significantly overlaps the keyhole, the probability of collision at the given additional acceleration value is 0.0022. This result has been verified by the Monte Carlo method. Tests of 10000 random sets of orbital elements, which were found taking into account their correlation, have shown that 22 cases have resulted in virtual asteroids colliding with Earth in 2036. A plot of the probability of the collision against the value of A2 has been constructed.