e-Pulsar - Feb

e-Pulsar The NEAR Shoemaker probe Feb - Mar 00

An Incredible Mission!

It's a dream come true - a scientific satellite that not only succeeds in collecting over 10 times more data than expected, but it also accomplishes near-miraculous feats it wasn't even designed for. That little miracle machine is the NEAR-Shoemaker probe.
2nd to last NEAR image, from 1200 feet Named for the late legendary geologist Gene Shoemaker, the 1700 pound probe (with fuel) was designed and built by the Johns Hopkins University Applied Physics Laboratory and launched towards asteroid 433 Eros atop a Delta-2 rocket from Cape Canaveral on 17 Feb 1996. After a 4-year journey, the NEAR-Shoemaker finally arrived at Eros on 14 Feb 2000 and began examining the 21-mile wide irregular shaped asteroid in great detail. Sporting six instruments: a magnetometer, an X-Ray/Gamma-Ray Spectrometer (consisting of two sensors), a Multispectral Imager (the electronic camera), a Laser Rangefinder, and a Near-Infrared Spectrometer, NEAR Shoemaker shot over 160,000 photos and collected trillions of bits of data. The spacecraft, about the size of a small car, is made of eight 18-square-foot aluminum panels, and is 9 feet, 2 inches long when you include its main antenna. Its four solar panels, each 6 feet long and 4 feet wide, surround the 5-foot (1.5-meter) diameter high-gain antenna on top of the spacecraft. The projected total mission cost is $224.1 million, including $124.9 million for spacecraft development, $44.6 million for launch support and tracking, and $54.6 million for mission operations and data analysis. NEAR-Shoemaker's computer is a 16-bit machine called a 1750A. Based on a military standard that is about 10 years old, it runs at 12 MHz and has 256 KB of storage - equivalent to PCs produced in the mid-1980s!
Saddle region of Eros The NEAR Shoemaker mission was one of NASA's Discovery series. Its primary goal was to answer fundamental questions about the nature and origin of the many asteroids and comets close to Earth's orbit. Eros' pristine surface offers a look at conditions in space when the Earth formed more than 4.5 billion years ago. Mission data was not limited to 433 Eros though. On its journey to Eros, the probe took several unique images of Earth and the moon, Comet Hyakutake, and the Beehive and Pleiades star clusters. NEAR paid the first visit to a carbon-rich "C-type" asteroid, taking several images of 253 Mathilde in 1997. NEAR also made an important contribution to the study of cosmic gamma ray bursts as part of the Interplanetary Gamma Ray Burst Network. The probe's Gamma-Ray Spectrometer was modified after launch with a software patch that allowed it to detect gamma ray bursts.
South end of Eros Like any space mission, NEAR Shoemaker had its gliches, but in the end, it achieved far more than originally intended. After almost a year in orbit of 433 Eros, mission planners decided to "roll the dice" and try for some more risky science. On 12 Feb the probe was commanded to land on the asteroid. Scientists were just hoping for the probe to survive the crash, but much to their surprise, it gently coasted down to a three point landing on its frame and two solar panels. Not only did it survive, but it was in perfect health! In an even more incredible stroke of luck, the gamma ray spectroscope was pointed down at the surface. NASA extended the mission for 14 days, allowing scientists to collect gamma ray data 10 times more sensitive than orbital data. Finally, on 28 Feb 2001, over 5 years after launch, the probe was shut down, ending one of the most successful space missions ever.