NEOWISE Mission Concludes After Over a Decade of Asteroid and Comet Detection
NASA’s NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer) mission has officially come to an end. On Thursday, engineers commanded the spacecraft to turn off its transmitter for the final time, marking the conclusion of over ten years of service dedicated to planetary defense. NEOWISE’s mission was to search for asteroids and comets, including those that could pose a threat to Earth.
The final command was transmitted from NASA’s Earth Orbiting Missions Operation Center at the Jet Propulsion Laboratory (JPL) in Southern California. The event was attended by both past and present mission members, along with officials from NASA headquarters in Washington. The signal was relayed via NASA’s Tracking and Data Relay Satellite System to NEOWISE, effectively decommissioning the spacecraft. As previously shared by NASA, the science survey conducted by NEOWISE ended on July 31, and all remaining data was successfully downlinked from the spacecraft.
"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," said Nicola Fox, Associate Administrator of the Science Mission Directorate at NASA Headquarters. "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 Reason for Mission Termination
NASA decided to end the mission as NEOWISE will soon drop too low in its orbit around Earth to provide usable scientific data. An increase in solar activity is heating the upper atmosphere, causing it to expand and create drag on the spacecraft, which lacks a propulsion system to maintain its orbit. Now decommissioned, NEOWISE is expected to safely burn up in Earth’s atmosphere by late 2024.
A Double Mission Success
During its operational lifetime, the infrared survey telescope exceeded scientific objectives for not one but two missions. Initially launched as the WISE (Wide-field Infrared Survey Explorer) mission in December 2009, it was designed for a seven-month mission to scan the entire infrared sky. By July 2010, WISE had accomplished this with far greater sensitivity than previous surveys. However, the telescope soon ran out of the coolant needed to prevent heat produced by the spacecraft from interfering with its infrared observations. Despite this, NASA extended the mission under the name NEOWISE until February 2011 to complete a survey of the main belt asteroids, after which the spacecraft was put into hibernation.
Analysis of the data showed that although the lack of coolant meant the space telescope could no longer observe the faintest infrared objects, it could still make precise observations of asteroids and comets that generate a strong infrared signal from being heated by the Sun as they travel past Earth.
NASA reactivated the telescope in 2013 under the Near-Earth Object Observations Program, a precursor to the agency’s Planetary Defense Coordination Office, to continue the NEOWISE survey of asteroids and comets for planetary defense purposes.
"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," said Laurie Leshin, Director, NASA JPL. "As we bid farewell to NEOWISE, we also celebrate the team behind it for their impressive achievements."
Achievements and Legacy
By repeatedly observing the sky from low Earth orbit, NEOWISE created all-sky maps featuring 1.45 million infrared measurements of more than 44,000 solar system objects. Of the over 3,000 near-Earth objects it detected, 215 were first spotted by NEOWISE. The mission also discovered 25 new comets, including the famed comet C/2020 F3 NEOWISE that streaked across the night sky in the summer of 2020.
In addition to leaving behind a wealth of scientific data, the spacecraft has helped inform the development of NASA’s first infrared space telescope purpose-built for detecting near-Earth objects: the NEO Surveyor.
"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," said Amy Mainzer, principal investigator for both NEOWISE and NEO Surveyor at the University of California, Los Angeles. "But its additional legacy is that it has helped lay the groundwork for NASA’s next planetary defense infrared space telescope."
Future Prospects: NEO Surveyor
Managed by JPL, the NEO Surveyor will seek out some of the hardest-to-find near-Earth objects, such as dark asteroids and comets that don’t reflect much visible light, as well as objects that approach Earth from the direction of the Sun. This next-generation infrared space telescope will significantly enhance the capabilities of the international planetary defense community, which includes NASA-funded ground surveys. Construction of NEO Surveyor is already well underway, with a launch date set for no earlier than 2027.
More Mission Information
The NEOWISE and NEO Surveyor missions support the objectives of NASA’s Planetary Defense Coordination Office. The NASA Authorization Act of 2005 directed NASA to discover and characterize at least 90% of the near-Earth objects more than 460 feet (140 meters) across that come within 30 million miles (48 million kilometers) of Earth’s orbit. Objects of this size can cause significant regional damage, or worse, should they impact the Earth.
NASA JPL manages and operates the NEOWISE mission for the agency’s Planetary Defense Coordination Office within the Science Mission Directorate. The Space Dynamics Laboratory in Logan, Utah, built the science instrument, while BAE Systems of Boulder, Colorado, built the spacecraft. Science data processing, archiving, and distribution is handled at IPAC at Caltech in Pasadena, California. Caltech manages JPL for NASA.
To learn more about NEOWISE, visit: NASA NEOWISE
Final Thoughts
The NEOWISE mission has been a cornerstone in our understanding of near-Earth objects and planetary defense. While it’s sad to see the mission come to an end, the data and discoveries it has provided will continue to benefit science and planetary defense efforts for many years to come. The legacy of NEOWISE will live on through the NEO Surveyor and the ongoing efforts to safeguard our planet from potential cosmic threats.
For more information or to get in touch with the mission team, you can contact:
- Karen Fox / Alana Johnson at NASA Headquarters, Washington: karen.c.fox@nasa.gov / alana.r.johnson@nasa.gov
- Ian J. O’Neill at Jet Propulsion Laboratory, Pasadena, Calif.: ian.j.oneill@jpl.nasa.gov
For more Information, Refer to this article.
