How did IBEX get into space?
An artistís rendition of the launch of a Pegasus rocket.
Image Credit: The Adler Planetarium
IBEX began its ride from Kwajalein Atoll, Marshall Islands in the middle of the Pacific Ocean on October 19, 2008. Kwajalein Atoll is southwest of Hawaii in the middle between Hawaii and Australia, near the Earth’s equator.
Satellites launched from a location close to the equator in an eastward direction benefit from the added "kick" that the rotation of the Earth provides, which is around an extra 1,000 miles per hour. This results in a fuel savings for the spacecraft launched from Kwajalein.
An L–1011 airplane took the Pegasus rocket and the attached IBEX spacecraft to a high altitude. At the right altitude, the Pegasus rocket was dropped from underneath the airplane. A few seconds later, the Pegasus fired its own rockets to propel it and IBEX into space. The satellite had its own small rocket engine that allowed it to climb into a highly elliptical orbit that took it 5/6 of the distance to the orbit of the Moon, or around 200,000 miles (325,000 km) away, at its farthest point, and about 10,000 miles (16,000 km), at its closest point. Even though the farthest point of this orbit was high, it was still very far from the boundary of the Solar System. The distance to the near edge of the heliosphere is around 9 billion miles (14 billion km) from the Earth, or about 90 times the distance between the Earth and the Sun.
It is important to remember that IBEX does not travel to the Solar System boundary; it is an Earth–orbiting satellite. It detects particles coming from the boundary toward our region of the Solar System.