NASA’s NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer) mission has officially concluded after more than a decade of significant contributions to planetary defense. On Thursday, engineers commanded the spacecraft to shut down its transmitter for the final time, marking the end of a mission dedicated to searching for asteroids and comets that could pose a threat to Earth.
The final command was issued from the Earth Orbiting Missions Operation Center at NASA’s Jet Propulsion Laboratory (JPL) in Southern California. Mission members, both past and present, along with officials from NASA headquarters in Washington, were in attendance. The decommissioning of NEOWISE was facilitated by NASA’s Tracking and Data Relay Satellite System, bringing the mission to a close after its last science data was downlinked on July 31.
Nicola Fox, associate administrator of the Science Mission Directorate at NASA Headquarters, reflected on the mission’s impact: “The NEOWISE mission has been an extraordinary success story as it helped us better understand our place in the universe by tracking asteroids and comets that could be hazardous for us on Earth. While we are sad to see this brave mission come to an end, we are excited for the future scientific discoveries it has opened by setting the foundation for the next generation planetary defense telescope.”
The decision to end the mission came as NEOWISE’s orbit around Earth began to degrade due to increasing solar activity, which is causing the upper atmosphere to expand and create drag on the spacecraft. Without a propulsion system, NEOWISE will continue to descend until it safely burns up in Earth’s atmosphere, likely by late 2024.
Launched in December 2009 as the WISE (Wide-field Infrared Survey Explorer) mission, the infrared survey telescope surpassed its original objectives, completing a comprehensive scan of the infrared sky by July 2010. Despite running out of coolant, which limited its ability to observe faint infrared objects, NASA extended the mission as NEOWISE to focus on tracking asteroids and comets that emit strong infrared signals when heated by the Sun.
In 2013, NASA reactivated the telescope under the Near-Earth Object Observations Program, a precursor to the Planetary Defense Coordination Office, to continue its vital work in monitoring near-Earth objects (NEOs).
Laurie Leshin, director of NASA JPL, praised the mission’s achievements: “The NEOWISE mission has been instrumental in our quest to map the skies and understand the near-Earth environment. Its huge number of discoveries have expanded our knowledge of asteroids and comets, while also boosting our nation’s planetary defense.”
Throughout its operational life, NEOWISE produced over 1.45 million infrared measurements of more than 44,000 solar system objects, including the detection of over 3,000 near-Earth objects, 215 of which were first spotted by NEOWISE. The mission also discovered 25 new comets, including the well-known comet C/2020 F3 NEOWISE.
As NEOWISE ends, it leaves behind a legacy of valuable data that will benefit scientists for decades. The mission also paved the way for NASA’s next planetary defense initiative, the NEO Surveyor, an advanced infrared space telescope set to launch no earlier than 2027. This next-generation telescope, managed by JPL, will enhance the global effort to detect and monitor near-Earth objects, particularly those that are difficult to observe using visible light.
Amy Mainzer, principal investigator for both NEOWISE and NEO Surveyor, emphasized the mission’s enduring impact: “The NEOWISE mission has provided a unique, long-duration data set of the infrared sky that will be used by scientists for decades to come. But its additional legacy is that it has helped lay the groundwork for NASA’s next planetary defense infrared space telescope.”
The NEOWISE and upcoming NEO Surveyor missions support the objectives of NASA’s Planetary Defense Coordination Office, which was directed by the NASA Authorization Act of 2005 to discover and characterize at least 90% of near-Earth objects more than 460 feet in size that come within 30 million miles of Earth’s orbit. These objects have the potential to cause significant damage if they were to impact the planet.
NASA’s Jet Propulsion Laboratory manages the NEOWISE mission for the agency’s Planetary Defense Coordination Office within the Science Mission Directorate. The Space Dynamics Laboratory built the science instrument, while BAE Systems constructed the spacecraft. Science data processing, archiving, and distribution are handled by IPAC at Caltech in Pasadena, California.–News Desk