NASA’s NEOWISE mission discovers 97 new asteroids, comets
During its third year of operation, NASA’s Near-Earth Object Wide-field Survey Explorer (NEOWISE) spacecraft discovered 97 hitherto unknown objects in the Solar System, including 28 that are near-Earth objects (NEOs).
Also, according to data released by the NEOWISE mission team, 64 of the 97 newly identified objects are asteroids in the main belt between Mars and Jupiter, while five of them are comets.
In addition to making a plethora of discoveries, NEOWISE also revealed new data about known asteroids and comets.
“NEOWISE is not only discovering previously uncharted asteroids and comets, but it is providing excellent data on many of those already in our catalog,” said Amy Mainzer, NEOWISE mission principal investigator from NASA’s Jet Propulsion Laboratory (JPL) in California. “It is also proving to be an invaluable tool in the refining and perfecting of techniques for near-Earth Object discovery and characterization by a space-based infrared observatory.”
NEOWISE is the second incarnation of the Wide-field Infrared Survey Explorer (WISE), an infrared space telescope launched in 2009 to image 99 percent of the sky in the infrared.
After being placed in hibernation since completing that mission in 2011, the spacecraft was reactivated in September 2013 as NEOWISE, with the new goal of identifying potentially hazardous near-Earth asteroids and comets as well as determining the sizes and compositions of similar, more distant objects.
Along with the announcement of its latest discoveries, the NEOWISE mission team created and published an animation depicting all findings made during the past year.
The more than 2.6 million infrared images of the sky captured in the mission’s third year have been added to the total data collected during the spacecraft’s first two years of operation, yielding an archive with 7.7 million image sets and over 57.7 billion sources revealed by those images.
Studies of these images have given scientists views of objects rarely seen, such as Comet C/2010 L5 (WISE). Using new computer modeling techniques, the researchers obtained new insights into the behavior of comets – especially sudden, brief outbursts that are unpredictable and, therefore, often missed.
One particular new technique, known as tail-fitting, uncovers the behavior history of individual comets by measuring the size and quantity of dust in their regions as well as the time since their ejection from the comet’s nucleus.
This technique could eventually make it possible for all-sky surveys to study cometary outbursts when they happen and collect important data from these events.
“Comets that have abrupt outbursts are not commonly found, but this may be due more to the sudden nature of the activity rather than their inherent rarity. It is great for astronomers to view and collect cometary data when they find an outburst, but since the activity is so short-lived, we may simply miss them most of the time,” said Emily Kramer, lead author of a study on the latest NEOWISE results and also a Postdoctoral Program Fellow at JPL.
NEOs, asteroids, and comets that have been pushed into Earth’s neighborhood through the gravitational influence of planets are of special interest to scientists because of the possibility, however small, that they could impact the Earth.
In its three years of operation, NEOWISE has cataloged 693 NEOs. Out of those discovered in the last year, ten asteroids, based on their orbits and sizes, have been deemed potentially hazardous.
Video courtesy of NASA Jet Propulsion Laboratory
Laurel Kornfeld is an amateur astronomer and freelance writer from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass College, Rutgers University, and earned a Graduate Certificate of Science from Swinburne University’s Astronomy Online program. Her writings have been published online in The Atlantic, Astronomy magazine’s guest blog section, the UK Space Conference, the 2009 IAU General Assembly newspaper, The Space Reporter, and newsletters of various astronomy clubs. She is a member of the Cranford, NJ-based Amateur Astronomers, Inc. Especially interested in the outer solar system, Laurel gave a brief presentation at the 2008 Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in Laurel, MD.