NASA ends NEOWISE mission to hunt asteroids and comets

2 Jul. () –

After More than 14 years of science in spaceNASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) mission will end on July 31.

The end of NEOWISE, which uses a space telescope to search for asteroids and comets, is linked to the Sun. About every 11 years, our star experiences a cycle of increased activity that peaks during a period called solar maximum. Explosive events, such as solar flares and coronal mass ejections, become more frequent and heat up our planet’s atmosphere, causing it to expand.

Atmospheric gases, in turn, increase the drag on satellites orbiting Earth, slowing them down. With the Sun currently rising to predicted maximum levels of activity, And without a propulsion system to keep NEOWISE in orbit, the spacecraft will soon sink too low to be usable.

TWO MISSIONS IN ONE

The infrared telescope will stop working after it has exceeded scientific objectives for not one, but two missions, starting as WISE (Wide-field Infrared Survey Explorer).

WISE, managed by NASA’s Jet Propulsion Laboratory in Southern California, was launched in December 2009 with a six-month mission to scan the entire infrared sky. By July 2010, WISE had accomplished this with much greater sensitivity than previous surveys, and NASA extended the mission until 2011.

During this phase, WISE studied distant galaxies, gas-spewing comets, exploding white dwarf stars and brown dwarfs. It identified tens of millions of actively feeding supermassive black holes. It also generated data on circumstellar disks — clouds of gas, dust and debris that swirl around stars — that citizen scientists continue to mine through the Disk Detective project.

In addition, it excelled in the search for main belt asteroids as well as near-Earth objects, and discovered the first terrestrial trojan asteroid known. In addition, the mission provided a census of dark, faint near-Earth objects that are difficult for ground-based telescopes to detect, revealing that these objects make up a sizable fraction of the near-Earth object population.

Invisible to the naked eye, warm objects emit infrared wavelengths. To prevent the heat generated by WISE itself from interfering with its infrared observations, the spacecraft relied on a cryogenic coolant. By the time its coolant ran out, WISE had mapped the sky twice, and NASA put the spacecraft into hibernation in February 2011.

Shortly afterward, Mainzer and his team proposed a new mission for the spacecraft: to search for, track, and characterize near-Earth objects that generate a strong infrared signal from their heating by the Sun.

“Without coolant, we had to find a way to cool the spacecraft enough to measure infrared signals from asteroids,” he said. it’s a statement Joseph Masiero, NEOWISE deputy principal investigator and a scientist at IPAC, a research organization at Caltech in Pasadena, California. “By commanding the telescope to stare into deep space for several months, we determined that it would radiate just enough heat to reach lower temperatures that would still allow us to acquire high-quality data.” NASA reactivated the mission in 2013. under the Near-Earth Object Observations Program, a precursor to the agency’s current planetary defense program, renamed NEOWISE.

By repeatedly observing the sky from low Earth orbit, NEOWISE has made 1.45 million infrared measurements of more than 44,000 solar system objects to date. That includes more than 3,000 NEOs, 215 of which the space telescope discovered. Twenty-five of these are comets, including the famous Comet NEOWISE, which was visible in the night sky in the summer of 2020.

“The spacecraft has exceeded all expectations and provided a wealth of data that the scientific community will use for decades to come,” said Joseph Hunt, NEOWISE project manager at JPL. “The scientists and engineers who worked on and through WISE have also built a knowledge base that will continue to provide valuable insights.” will help inform future infrared survey missions.”

The space telescope will continue its study until July 31. Then, on August 8, mission controllers at JPL will send a command that puts NEOWISE into hibernation for the last time. Since its launch, NEOWISE’s orbit has been getting closer to Earth. NEOWISE is expected to burn up in our planet’s atmosphere sometime between late 2024 and early 2025.

NEW INFRARED SPACE TELESCOPE FOR 2027

Another NASA mission is taking shape, building on experience gained with NEOWISE: NASA’s NEO Surveyor (Near Earth Object Surveyor), the first infrared space telescope built specifically to search for dangerous near-Earth objects. Scheduled for launch in late 2027will be a major step forward in the agency’s planetary defense strategy, according to NASA.

“After developing new techniques to find and characterize near-Earth objects hidden in vast amounts of its infrared survey data, NEOWISE has become key to helping us develop and operate NASA’s next-generation infrared space telescope. It is a precursor mission“NEO Surveyor will search for the most elusive asteroids and comets that could cause significant damage to Earth if we don’t find them first,” said Amy Mainzer, principal investigator for NEOWISE and NEO Surveyor at the University of California, Los Angeles, in a statement.