Session
Technical Session I: National Needs & Objectives
Abstract
On February 12th, 2001, the NEAR Shoemaker spacecraft made its historic descent to the surface of the asteroid 433 Eros, becoming the first spacecraft to soft land on a small celestial body. Development of the final descent activity offered the NEAR team a difficult technical challenge as the spacecraft had been designed solely as a free flyer, not as a lander. The NEAR Shoemaker spacecraft rendezvoused with 433 Eros on February 14th, 2000. Following an intensive year of orbital operations collecting science data at decreasingly lower altitudes, the spacecraft was prepared to conduct its final activity, descending from its current 36 km orbit in a series of five propulsive maneuvers to land on the surface of 433 Eros. As a free flyer, the spacecraft’s orbital operations were extremely successful, collecting an order of magnitude more images of the asteroid’s surface than originally planned. However, since the spacecraft was not designed to be a lander, landing presented a whole new challenge to the Navigation, Mission Design, Guidance and Control, and Mission Operations Teams. This paper discusses the development of the controlled descent sequence from an operations perspective, focusing on the inherent difficulties of performing an activity for which the spacecraft was not originally designed, and the way in which these challenges were overcome by the NEAR team.
433 Eros Landing – Development of NEAR Shoemaker’s Controlled Descent Sequence
On February 12th, 2001, the NEAR Shoemaker spacecraft made its historic descent to the surface of the asteroid 433 Eros, becoming the first spacecraft to soft land on a small celestial body. Development of the final descent activity offered the NEAR team a difficult technical challenge as the spacecraft had been designed solely as a free flyer, not as a lander. The NEAR Shoemaker spacecraft rendezvoused with 433 Eros on February 14th, 2000. Following an intensive year of orbital operations collecting science data at decreasingly lower altitudes, the spacecraft was prepared to conduct its final activity, descending from its current 36 km orbit in a series of five propulsive maneuvers to land on the surface of 433 Eros. As a free flyer, the spacecraft’s orbital operations were extremely successful, collecting an order of magnitude more images of the asteroid’s surface than originally planned. However, since the spacecraft was not designed to be a lander, landing presented a whole new challenge to the Navigation, Mission Design, Guidance and Control, and Mission Operations Teams. This paper discusses the development of the controlled descent sequence from an operations perspective, focusing on the inherent difficulties of performing an activity for which the spacecraft was not originally designed, and the way in which these challenges were overcome by the NEAR team.
