by Clarence Oxford
Los Angeles CA (SPX) Nov 05, 2024
NASA's NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer) mission concluded as planned on Friday night when the spacecraft re-entered Earth's atmosphere, burning up after nearly 15 years in orbit. Originally launched in 2009 as the WISE mission, this resilient spacecraft dedicated itself to capturing infrared images of the sky and revealing unseen aspects of the cosmos.
Throughout its mission, NEOWISE not only cataloged data that professional astronomers used but also involved over 100,000 citizen scientists worldwide. These contributors engaged in various projects, including the Milky Way Project, Disk Detective, Backyard Worlds: Planet 9, Backyard Worlds: Cool Neighbors, and Exoasteroids. Such initiatives have significantly expanded our understanding of the universe, contributing to over 55 scientific papers.
Some standout findings from NEOWISE-supported citizen science include:
Identification of Yellowballs: Yellowballs are bright, compact regions that represent early stages of star formation. These objects, noted by citizen scientists in infrared data, are thought to be sites where massive stars are forming in dense gas and dust clouds. Studying Yellowballs provides insight into high-mass star formation, which influences galactic structure and star-forming processes.
Discovery of Peter Pan Disks: Known for their "never-growing-up" nature, Peter Pan Disks are gas and dust disks that persist around low-mass stars far longer than usual. Typically, these disks disperse within a few million years, but Peter Pan Disks defy this trend. This finding challenges current theories of disk evolution, shedding light on planetary formation in low-mass systems.
Detection of the First Extreme T Subdwarfs: Extreme T subdwarfs are rare, ultra-cool stars or brown dwarfs with low metal content, representing some of the galaxy's oldest populations. The discovery of these objects allows astronomers to study star formation in the early Milky Way, offering a glimpse into the chemical environment billions of years ago and the formation of low-mass stellar objects.
Possible Auroras on Brown Dwarfs: Brown dwarfs, often called "failed stars," exist between stars and planets in mass. Observations from NEOWISE suggest auroras on brown dwarfs, similar to those seen on planets like Earth and Jupiter. This potential discovery offers insights into atmospheric and magnetic activity on these objects, linking stellar and planetary atmospheric studies.
Substellar Mass Function Measurements Down to ~400 K: The substellar mass function describes the population of brown dwarfs and low-mass objects in the galaxy. NEOWISE's data enabled measurements of these objects down to 400 K, cooler than most previously detected. Extending this range refines models of stellar formation and aids in distinguishing the boundaries between planets and brown dwarfs.
Oldest Known White Dwarf with a Disk: White dwarfs are the remnants of stars like our Sun, and NEOWISE data revealed the oldest known white dwarf with a surrounding disk. Such disks usually dissipate quickly, so this discovery suggests recent planetary collisions or interactions. It offers a rare opportunity to study planetary system evolution around ancient stars.
Possible Detection of a Planetary Collision: NEOWISE data has shown evidence of a potential collision between two planets or planetary embryos. High-impact events like these shape planetary systems, as dust and rocks combine or break apart. This observation offers insights into planetary formation and may mirror the early evolution of our own solar system.
Discovery of the Lowest-Mass Hypervelocity Star: Hypervelocity stars move at extraordinary speeds, often propelled by supermassive black holes or other violent events. NEOWISE data led to the discovery of the lowest-mass hypervelocity star. Studying such stars enhances our understanding of galactic dynamics and allows astronomers to map gravitational interactions across the galaxy.
Even though NEOWISE is no longer operational, the data it gathered continues to be a vital resource. Its extensive catalog contains trillions of observations, offering years of exploration for citizen science projects such as Disk Detective, Backyard Worlds: Planet 9, Backyard Worlds: Cool Neighbors, and Exoasteroids. Researchers and amateur scientists alike are invited to dive into this rich dataset to uncover more mysteries of the infrared universe.
Related Links
NEOWISE
Asteroid and Comet Mission News, Science and Technology