Scientists believe they have the first seven specks of freshly plucked dust from exploded stars and other cosmic phenomena beyond the solar system.

A NASA spacecraft launched 15 years ago to find samples from a comet also detected what scientists suspect are the first dust specks from interstellar space.

The spacecraft was launched back in 1999 to fly by a comet and collect samples from Comet Wild 2 (pronounced "Vilt 2") and parachute back to Earth in 2006.

Before reaching the comet, the spacecraft also opened a collection tray of fish twice for particles that might have come into the solar system from interstellar space, according to Reuters.

The grains are surprisingly diverse in shape, content, and size, meaning that interstellar dust likely has a more complex and varied evolution than originally believed, said lead author Andrew Westphal, a physicist with the University of California Berkeley's Space Science Laboratory.

Two of the particles are bigger than the rest, which is a very relative term when considering the specks are about 4 microns, or one-16,000th of an inch (0.0004 cm) across, according to Reuters.

The two dust grains, which look like fluffy snowflakes, contain a magnesium-iron-silicate mineral called olivine, an indication that they might have come from disks around other stars before being sent out by interstellar travel, Westphal said.

Some of the interstellar grains could have organics as well, added space scientist Michael Zolensky, who oversees NASA's collection of extraterrestrial samples at the Johnson Space Center in Houston.

Scientists are now hoping to tease out more information from the dust motes, but aren't quite ready yet, according to Reuters. They believe that more sophisticated equipment and processes are required to analyze the tiny samples without destroying them.

"The prudent thing is just to put these away for a while and then wait until better techniques come along to make the analysis," Zolensky said, according to Reuters.

Their work was described in a paper in this week's edition of the journal Science.

The volunteer effort to locate other potential interstellar grains in Stardust's collection trays continues in the meantime.

"This takes real effort," Westphal said, according to Reuters. "You're not just launching your computer off on a project. You're having to do it yourself."

About 30,700 "dusters" have collectively done more than 100 million searches for interstellar dust particles by scanning digitized images of Stardust's translucent aerogel collectors, according to Reuters.

See Now: OnePlus 6: How Different Will It Be From OnePlus 5?