August 25, 1997 10:39 a.m. EDT
The Earth is constantly bombarded with high speed particles coming not only from the sun, but also from outside of the solar system. Studying these energetic particles can help us understand the origin and evolution of our solar system. The Advanced Composition Explorer (ACE) spacecraft carries nine instruments that can collect and measure these particles 10 to 1000 times better than previous spacecraft. From ACE, Scientists on Earth will receive information about the solar wind such its velocity, temperature, and composition.
ACE will orbit the sun very near the Earth (approximately 1/100 of the distance from the Earth to the sun). From here it will be able to determine which particles hit the Earth. This information will help scientists to better understand phenomena such as solar flares. Ace will also be able to warn us of encroaching geomagnetic storms that disrupt communications and are hazardous to astronauts.
|Mass:||785 kg (includes 189 kg fuel)|
|Structure:||Two octagonal decks, 1.6 m across, 1.0 m high|
|Propulsion:||Hydazine, for insertion and maintenance in orbit|
|Power:||443 W, four fixed solar arrays|
|Attitude Subsystem:||Spinning spacecraft; spin axis; Earth/Sun pointing|
|Communications:||S-band, 7 kbps (real time), 1 Gbit (total) solid state recorders|
|Launch Vehicle:||Delta II|
|Primary Mission:||Observe energetic particles within the solar system|
|Mission Lifetime:||2 years/5-year goal|
Last Modified $Date: 2011-09-27 14:07:35-06 $