NASA scientists said they might have identified the first specks of interstellar dust in materials collected by the agency’s Stardust spacecraft.
The interstellar dust is comprised of tiny particles that take part in making stars and planets. The Stardust spacecraft’s primary job was to catch dust streaming from Comet Wild 2 and return it to Earth for analysis. However, scientists also hoped to collect particles of interstellar dust.
The material was collected in a 2.9 billion mile journey during the Stardust probe’s seven-year mission. The spacecraft used a retractable device containing cells filled with a material called aerogel, a porous substance that is designed to trap dust molecules. The capsule that contained the samples landed back on Earth in January 2006.
Team members now say that there might be two contemporary interstellar dust grains in the Stardust Interstellar Dust Collector (SIDC) deployed during the mission.
Dr. Andrew Westphal of the University of California announced the discovery at the Lunar and Planetary Science Conference (LPSC) in The Woodlands, Texas.
“There are two particles, but they are in the same track. So when they hit the aerogel, they were together – they are two components of the same particle,” Westphal told BBC News. “But they are very different from each other. That in itself is interesting, because if this does turn out to be interstellar dust, then it is a bit more heterogeneous than people thought.”
Bruce Hudson found the first speck. After discovering he named the particle “Orion.”A group of scientists later discovered another grain, which Hudson donned “Sirius.”
However, Westphal said that the find “could be a false alarm.”
“The right way to say it is we’re cautiously excited,” he said. “We have very limited data on it so far and the reason is deliberate. The analyses we are doing have the potential to do some minor damage to the particles. We don’t think it will and we’ll be careful to limit our analyses.”