Disk Detective: Search for Planetary Habitats
A new NASA-sponsored website, DiskDetective.org, lets the public discover embryonic planetary systems hidden among data from NASA's Wide-field Infrared Survey Explorer (WISE) mission.
The site is led and funded by NASA and developed by the Zooniverse, a collaboration of scientists, software developers and educators who collectively develop and manage the Internet's largest, most popular and most successful citizen science projects.
WISE, located in Earth orbit and designed to survey the entire sky in infrared light, completed two scans between 2010 and 2011. It took detailed measurements of more than 745 million objects, representing the most comprehensive survey of the sky at mid-infrared wavelengths currently available. Astronomers have used computers to search this haystack of data for planet-forming environments and narrowed the field to about a half-million sources that shine brightly in the infrared, indicating they may be "needles": dust-rich circumstellar disks that are absorbing their star's light and reradiating it as heat.
Planets form and grow within these disks. But galaxies, interstellar dust clouds, and asteroids also glow in the infrared, which stymies automated efforts to identify planetary habitats.
Disk Detective incorporates images from WISE and other sky surveys in the form of brief animations the website calls flip books. Volunteers view a flip book and then classify the object based on simple criteria, such as whether the image is round or includes multiple objects. By collecting this information, astronomers will be able to assess which sources should be explored in greater detail.
The project aims to find two types of developing planetary environments. The first, known as young stellar object disks, typically are less than 5 million years old, contain large quantities of gas, and are often found in or near young star clusters. For comparison, our own solar system is 4.6 billion years old.
The other type of habitat is called a debris disk. These systems tend to be older than 5 million years, possess little or no gas, and contain belts of rocky or icy debris that resemble the asteroid and Kuiper belts found in our own solar system. Vega and Fomalhaut, two of the brightest stars in the sky, host debris disks.
Through Disk Detective, volunteers will help the astronomical community discover new planetary nurseries that will become future targets for NASA's Hubble Space Telescope and its successor, the James Webb Space Telescope.