## On the Nongravitational Acceleration in the Motion of the Near–Earth Asteroids

Transactions of IAA RAS, issue 56, 48–54 (2021)

**DOI**: 10.32876/ApplAstron.56.48-54

**Keywords**:
asteroid, orbit, nongravitational acceleration, parameters of nongravitational acceleration, the Yarkovsky effect, geometric albedo, diameter

### Abstract

For 294 Near-Earth Asteroids (NEAs), having optical and radar observations, the values of the parameters $А_2$ and $А_3$ of the nongravitational acceleration (NGA), caused, as we believe, by the Yarkovsky effect, were obtained. 145 asteroids for which errors $А_2 < 0.5 × 10^{–14}$ AU day$^{-2}$ were selected for further analysis, and such solutions can be considered reliable. The obtained values of the NGA parameters are compared with the sizes of asteroids and the values of the geometric albedo. It is possible to note some correlation between the values of the parameters $А_2$ and $А_3$ with the values of the diameters of asteroids — $|А_2|$ and $|А_3|$ increase when diameters decrease. The values of $А_2$ and $|А_3|$ are compared with the corresponding values of the orbital latitude of the asteroid rotation poles. The expected dependence on the position of the axes of rotation of asteroids, in general, is observed: 1) $А_2$ is negative for reverse rotation and positive for forward rotation; 2) $|А_3|$ is maximal if the axis of rotation lies near the orbital plane. Assuming a constant value of the angle of thermal lag of 1°, the values of $А_1$ were estimated from the values of $А_2$ and then the values of the total nongravitational acceleration $\bar{A}$ ($|\bar{A}|^{2}=\mathrm{A}_{1}^{2}+\mathrm{A}_{2}^{2}+\mathrm{A}_{3}^{2}$) were calculated. It was proved, that $\bar{A}$: $|\bar{A}|<\sim \cdot(5-10) \times 10^{-11}$ AU day$^{-2}$, which is about 4 orders of magnitude less than the acceleration caused, on average, by cometary sublimation ($\sim 10^{-7}-10^{-8}$ AU day$^{-2}$). This estimate can be useful for distinguishing between the manifestations of cometary sublimation and the Yarkovsky effect by revising the motion of asteroids with signs of cometary activity: if obtained estimations of NGA are greater than this value, most likely, this NGA is caused by sublimation.

### Citation

`Yu. A. Chernetenko, V. B. Kuznetsov. On the Nongravitational Acceleration in the Motion of the Near–Earth Asteroids // Transactions of IAA RAS. — 2021. — Issue 56. — P. 48–54.`

```
@article{chernetenko2021,
abstract = {For 294 Near-Earth Asteroids (NEAs), having optical and radar observations, the values of the parameters $А_2$ and $А_3$ of the nongravitational acceleration (NGA), caused, as we believe, by the Yarkovsky effect, were obtained. 145 asteroids for which errors $А_2 < 0.5 × 10^{–14}$ AU day$^{-2}$ were selected for further analysis, and such solutions can be considered reliable.
The obtained values of the NGA parameters are compared with the sizes of asteroids and the values of the geometric albedo. It is possible to note some correlation between the values of the parameters $А_2$ and $А_3$ with the values of the diameters of asteroids — $|А_2|$ and $|А_3|$ increase when diameters decrease. The values of $А_2$ and $|А_3|$ are compared with the corresponding values of the orbital latitude of the asteroid rotation poles. The expected dependence on the position of the axes of rotation of asteroids, in general, is observed: 1) $А_2$ is negative for reverse rotation and positive for forward rotation; 2) $|А_3|$ is maximal if the axis of rotation lies near the orbital plane.
Assuming a constant value of the angle of thermal lag of 1°, the values of $А_1$ were estimated from the values of $А_2$ and then the values of the total nongravitational acceleration $\bar{A}$ ($|\bar{A}|^{2}=\mathrm{A}_{1}^{2}+\mathrm{A}_{2}^{2}+\mathrm{A}_{3}^{2}$) were calculated. It was proved, that $\bar{A}$: $|\bar{A}|<\sim \cdot(5-10) \times 10^{-11}$ AU day$^{-2}$, which is about 4 orders of magnitude less than the acceleration caused, on average, by cometary sublimation ($\sim 10^{-7}-10^{-8}$ AU day$^{-2}$). This estimate can be useful for distinguishing between the manifestations of cometary sublimation and the Yarkovsky effect by revising the motion of asteroids with signs of cometary activity: if obtained estimations of NGA are greater than this value, most likely, this NGA is caused by sublimation.},
author = {Yu.~A. Chernetenko and V.~B. Kuznetsov},
doi = {10.32876/ApplAstron.56.48-54},
issue = {56},
journal = {Transactions of IAA RAS},
keyword = {asteroid, orbit, nongravitational acceleration, parameters of nongravitational acceleration, the Yarkovsky effect, geometric albedo, diameter},
pages = {48--54},
title = {On the Nongravitational Acceleration in the Motion of the Near–Earth Asteroids},
url = {http://iaaras.ru/en/library/paper/2083/},
year = {2021}
}
```

```
TY - JOUR
TI - On the Nongravitational Acceleration in the Motion of the Near–Earth Asteroids
AU - Chernetenko, Yu. A.
AU - Kuznetsov, V. B.
PY - 2021
T2 - Transactions of IAA RAS
IS - 56
SP - 48
AB - For 294 Near-Earth Asteroids (NEAs), having optical and radar
observations, the values of the parameters $А_2$ and $А_3$ of the
nongravitational acceleration (NGA), caused, as we believe, by the
Yarkovsky effect, were obtained. 145 asteroids for which errors $А_2
< 0.5 × 10^{–14}$ AU day$^{-2}$ were selected for further analysis,
and such solutions can be considered reliable. The obtained values
of the NGA parameters are compared with the sizes of asteroids and
the values of the geometric albedo. It is possible to note some
correlation between the values of the parameters $А_2$ and $А_3$ with
the values of the diameters of asteroids — $|А_2|$ and $|А_3|$
increase when diameters decrease. The values of $А_2$ and $|А_3|$ are
compared with the corresponding values of the orbital latitude of the
asteroid rotation poles. The expected dependence on the position of
the axes of rotation of asteroids, in general, is observed: 1) $А_2$
is negative for reverse rotation and positive for forward rotation;
2) $|А_3|$ is maximal if the axis of rotation lies near the orbital
plane. Assuming a constant value of the angle of thermal lag of 1°,
the values of $А_1$ were estimated from the values of $А_2$ and then
the values of the total nongravitational acceleration $\bar{A}$ ($|\
bar{A}|^{2}=\mathrm{A}_{1}^{2}+\mathrm{A}_{2}^{2}+\mathrm{A}_{3}^{2}$
) were calculated. It was proved, that $\bar{A}$: $|\bar{A}|<\sim
\cdot(5-10) \times 10^{-11}$ AU day$^{-2}$, which is about 4 orders
of magnitude less than the acceleration caused, on average, by
cometary sublimation ($\sim 10^{-7}-10^{-8}$ AU day$^{-2}$). This
estimate can be useful for distinguishing between the manifestations
of cometary sublimation and the Yarkovsky effect by revising the
motion of asteroids with signs of cometary activity: if obtained
estimations of NGA are greater than this value, most likely, this NGA
is caused by sublimation.
DO - 10.32876/ApplAstron.56.48-54
UR - http://iaaras.ru/en/library/paper/2083/
ER -
```