Astonishing! Sample from Wild 2 comet is a blueprint of the universe

Almost two decades after the launch of NASA’s Stardust, the sample collected from the mission reveals some astonishingly new facts that no one expected. The minuscule sample collected from a known comet through the 1999 mission hides centuries of data in it, new findings suggest in the journal Geochemistry.

NASA’s Stardust mission was launched in 1999 to collect material from a comet called Wild 2. It was believed that the intriguing comet was formed beyond Neptune, which is currently said to be orbiting the Sun between Mars and Jupiter.

For years, scientists intricately analysed the first samples brought fromWild 2 to understand the origin of the comet. But to everyone’s surprise, the icy object’s interior came out to be a blueprint of the universe.

Minuscule cosmic sample that contains ages of history

When Stardust brought back a comet sample to Earth, many scientists opined that its rocky inside material might be made up of the primordial dust that built the solar system. This was one of the reasons why the mission was named ‘stardust’.

But the actual samples told a different story- Wild 2 contained a potpourri of dust that formed from different events early in the solar system's history.

The research was published by Ryan Ogliore, an associate professor of physics in Arts & Sciences at Washington University in St. Louis who has been studying the Stardust samples for several years.

For Ogliore, the discovery that Wild 2 contained a record of "local" events was exciting.

"The comet was a witness to the events that shaped the solar system into what we see today," he said.

The comet, being kept in cold storage for nearly its entire lifetime, protected it from any alteration from heat and water.

"Comet Wild 2 contains things we've never seen in meteorites, like unusual carbon-iron assemblages, and the precursors to igneous spherules that make up the most common type of meteorite," Ogliore said. "And all of these objects have been exquisitely preserved within Wild 2."

The discovery was made after interrogating the comet samples for nearly two decades. The amount of sample was so minuscule, less than one milligram (a grain of sand), that it required high precision to extract data from it.

Every part of that miniature sample has a different storyand it was a time-consuming process to analyse the extracted parts as well, says Ogliore.

Most of the Wild 2 particles are still unstudied and certainly hold many more surprises.

(With inputsfrom agencies)