Launching something into space isn’t easy — even small payloads like the Interstellar Boundary Explorer (IBEX), which weighs as much as the average 7-year-old child, are costly and complex. That’s why NASA and other space agencies design spaceflight hardware to last. The IBEX probe was launched 15 years ago, and there was some concern last month that the mission had reached the end of the line. However, NASA now says IBEX has been resurrected and is back at full operational capacity.
The problems started on Feb. 18 when a routine system reset caused the spacecraft to stop operating. NASA eventually learned that a flight computer error caused the satellite to enter safe mode. So, uploads reached the probe but were not being processed. Initial attempts to reset the spacecraft were unsuccessful.
NASA suspected that IBEX might come back online after an automatic system reset scheduled for March 4, but the agency opted to speed things up. IBEX is in a highly eccentric orbit around Earth, reaching a maximum altitude (apogee) of 220,866 kilometers (137,252 miles) and a minimum (perigee) of just 7,000 kilometers (4,300 miles). It hit perigee on March 2, and the team felt that was their best chance to restart the probe. The “firecode reset” command worked, and IBEX is again online.
IBEX was launched in 2008 to map the edge of the solar system. Engineers equipped it with two energetic neutral atom (ENA) imagers, IBEX-Hi and IBEX-Lo. Both instruments allow the probe to collect and separate ions of different energy levels. During its lifetime, IBEX has reported that the heliosphere has no bow shock, an area of higher density and energy where the sun’s magnetic field encounters interstellar plasma. It also found the relative speed of the heliosphere was 23.2 km/s, about half of the previous estimates. In 2013, IBEX revealed the heliosphere has a four-lobed tail on its trailing end.
In 2008, NASA only needed IBEX to last for two years, but it has long since surpassed that. As it comes up on 15 years in space, IBEX is still ready to make discoveries about the border of our solar system.