Volunteers Wanted To Help Hunt For Active Asteroids

FLAGSTAFF, Ariz. — Volunteer “citizen scientists” are being asked to search the sky for so-called active asteroids in an effort to find clues to two of the greatest mysteries of the universe: the origin of water, and whether there are extraterrestrials.

Of the estimated 10,000 asteroids in our solar system, fewer than 30 have been classified as active asteroids or asteroids with tails, prompting scientists to call for help from amateur sleuths to find a larger sample to study.

“With the generous help of ‘citizen scientists,’ we hope to quadruple the number of known active asteroids and encourage study of an ambiguous population of solar system objects, knowledge of which is currently hampered due to a very small sample size,” said researcher Colin Orion Chandler.

Chandler is pursuing a doctorate in astronomy at Northern Arizona University. With funding from the National Science Foundation (NSF), he has launched Active Asteroids, which he hopes will inspire volunteers to seek the celestial objects. 

“We need to examine 5,000 square degrees of the sky in the Southern Hemisphere, which means there are many — more than 10 million — asteroid images to classify,” he said.

Chandler has conducted a review phase of the project with assistance from more than 200 volunteers who completed 4,798 classifications of 295 objects. 

“I am very, very excited the project is finally launching,” he said. “It has been years in the making, from selection by the NSF until this launch. Even during the preparations for the project launch, we have made several important discoveries, including a new active object and uncovering information about several previously known objects. These discoveries have led to three publications in peer-reviewed scientific journals, with another one in the works right now.”

The project seeks to shed light on some of the most profound mysteries of the universe. 

“Asteroids with tails!? As strange as it may sound, these objects actually exist,” said Chandler. “They hold clues to where terrestrial water came from and where water in the solar system is located today.” 

Active asteroids could also be sources for fuel and air for future deep-space missions. Since there is often life where water is found, the project could also assist in the search for extraterrestrial life forms.

Chandler and the team have already made at least one discovery of note: They noticed during the project’s test phase that a “smudge” was repeatedly observed around a particular Centaur, an icy object in orbit between Jupiter and Neptune. Centaurs are minor planets that are difficult to observe. They sometimes feature comet-like tails and orbit in a region too cold to allow water to transition from a frozen solid to gas. 

Using telescopes, Chandler’s team made other observations and found that the object was active, and they had it re-categorized as a comet. Their findings on the Centaur were published in The Astrophysical Journal Letters. 

Chandler expects the active comet project to be completed within a year, and he plans to recruit thousands of “citizen scientists” to help. Training is provided to volunteers through Zooniverse, and participants are not required to have previous experience in astronomy. 

Edited by Matthew B. Hall and Judith Isacoff