Fragmentation of the HAYABUSA Spacecraft on Re-Entry
Abstract
We succeeded in monitoring fragmentation of the main body of the HAYABUSA spacecraft upon its re-entry as a part of an expedition by the National Astronomical Observatory of Japan. The time variation of the number of fragments and their size distribution were derived by analyzing obtained images. The fragmentation started at 13h52m5s.2 UT at 83-84 km above sea level, and the number of fragments increased with time. The maximum number was more than a few hundred at around 13h52m20s, and the fragments dispersed over an area of more than 14 km in length, and 1 km in width along the re-entry trajectory. Fragments decreased in number after the maximum, and almost disappeared at 13h52m31s.3 at around a height of 45 km. Under some assumptions, we managed to derive the size distribution of the fragments, which showed a small power-law index within a range of -0.8 to -1.0. These values are lower than those of fragmentations of comets, or other examples in our solar system. The obtained flat size distribution is discussed based on a comparison of the intrinsic size distribution of the assembled parts of the HAYABUSA spacecraft.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- October 2011
- DOI:
- Bibcode:
- 2011PASJ...63..955W
- Keywords:
-
- meteors;
- meteoroids;
- solar system: general;
- space vehicles: atmospheric re-entry;
- space vehicles: interplanetary mission;
- space vehicles: space aeronautics