Fragments of asteroids may have jumped the gap in the early solar system

August 4, 2020

Using some cosmic detective work, a team of researchers has found evidence that tiny pieces of asteroids from the inner solar system may have crossed a gap to the outer solar system, a feat once thought to be unlikely. 

About 1 million years after the start of the solar system, it is thought that while Jupiter’s core formed, it created a gap in the protoplanetary disk (the disk of dense gas and dust surrounding the sun). Called the “Jupiter Gap,” this divide severely limited material from getting across it and is thought to have created two distinct reservoirs in the disk. Atacama Large Millimeter Array image of the protoplanetary disk around HL Tauri. The dark rings are gaps in the dust and gas-rich protoplanetary disk, likely due to the formation of planets. These gaps may be similar to the disk gap thought to be formed by the formation of Jupiter in our protoplanetary disk. Credit: ESO/ALMA Download Full Image

Against the odds, however, a team of researchers including Associate Research Professor Devin L. Schrader and Research Scientist Jemma Davidson of Arizona State University’s Center for Meteorite Studies have found evidence in meteorites that tiny fragments of asteroids from the inner solar system crossed the Jupiter Gap into the outer solar system. The results of their study have been recently published in Geochimica et Cosmochimica Acta.

“This research provides new information about the dynamics of the early solar system,” lead author Schrader said. “Our research shows that these two reservoirs were not completely isolated from one another.”

The research team, which also includes scientists from the Smithsonian Institution’s National Museum of Natural History, the University of Hawaiʻi at Mānoa, Washington University in St. Louis, and Harvard University, were inspired to conduct this study because of samples brought back from NASA’s comet sample return mission, Stardust.

These samples hinted that comets could contain material that migrated from the inner solar system to the outer reaches where comets formed and suggested that the migration of material may have been more widespread in the early solar system than previously thought.

“The Stardust mission was like peeking through the blinds at the earliest solar system,” said co-author Timothy McCoy, chair and curator of meteorites at the National Museum of Natural History, Smithsonian Institution. “We knew that meteorites in our collections could open the window so that we could see the whole view”

With that in mind, they set out to test this hypothesis using samples of meteorites, specifically chondrites, that were present in the early solar system.

And thanks to the large collection of meteorites from the Center for Meteorite Studies, the Smithsonian Institution and NASA, they had access to samples of chondrites that were believed to have formed in the inner solar system as well as those believed to have been formed in the outer solar system.

Using electron probe microanalyzers (to obtain high resolution images of the samples and major and minor element data of individual minerals) and a secondary ion mass spectrometer (used to analyze the isotopic composition of samples), the team was able to provide direct evidence for a complex mixing of materials between the inner and outer solar system.

“By looking at the kinds of samples we have in the Center for Meteorite Studies collection, we were able to investigate how material moved around in the protoplanetary disk four and a half billion years ago,” co-author Davidson said.

In future studies, the team hopes to learn more from asteroid sample return missions like the Japanese Aerospace Exploration Agency’s Hayabusa2 mission to the asteroid Ryugu, which is scheduled to return samples to Earth later this year and NASA’s OSIRIS-REx to the asteroid Bennu, which is expected to return samples to Earth in 2023.    

Karin Valentine

Media Relations & Marketing manager, School of Earth and Space Exploration


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ASU ready to welcome incoming Sun Devils with traditions held in new ways.
August 4, 2020

Incoming class to be introduced to the university's campuses and its traditions in new formats

It’s unusual times during the COVID-19 pandemic, but Arizona State University has made an extraordinary shift to welcome another class of Sun Devils for fall semester.

Thousands of first-year students will be arriving on campus in the coming weeks to begin their studies, and ASU will provide a full slate of activities for Welcome Week and beyond.

Some of the most iconic events will be held virtually, such as Sun Devil Welcome. This pep rally gathering is typically held in Desert Financial Arena, which is packed with more than 13,000 screaming students — a scenario that wouldn’t be safe in 2020. So this year, Sun Devil Welcome will be held virtually at 4 p.m. Tuesday, Aug. 18.

But students also will be able to attend some in-person activities in small-group settings, with face coverings and physical distancing. These will include small-group residence hall floor meetings, plus walk-throughs of the Sun Devil Fitness Complex and “find-my-classes” tours of each campus, according to Joanne Vogel, vice president of student services at ASU.

The in-person activities will be organized by floors in an effort to encourage students to connect in-person in “bubbles” with their nearest peers, Vogel said.

“Students may choose to extend their social bubble beyond their roommates and suitemates to include others living on their floor or within their residence hall. But guests from other residence halls will not be allowed, as we’re asking all students to commit to limiting their in-person social interactions,” she said. “If you live in Hassayampa, you’re not allowed to visit Manzanita.”

Students also will participate in some small-group, “get-to-know-you” activities with their floormates, Vogel said.

“We’ll keep it safely distanced and informative, but we won’t leave out good old-fashioned fun,” she said.

Additionally, Sun Devil Fitness and Wellness is facilitating 170 intimate programs with students, focused on self-care and how to live well during fall semester. At the Tempe campus, students will learn skills in how to maintain “mindful moments” as well as how to “fill up (their) cup” during stressful times.

“We are hopeful that these skills will equip students with the skills they need to navigate the upcoming semester, and also provide them with skills in resiliency/strength,” said Julie Kipper, executive director of Sun Devil Fitness and Wellness at ASU.

Vogel said that ASU’s staff and students worked hard to build a start-of-the-year experience that would be meaningful for new and returning Sun Devils. That meant deciding whether some activities could still be held in person and which would be held virtually — and how to make those “remote” events creative and fun.

“We’ve put a lot of thought into these sessions to figure out the meaning behind every activity, what we hope to accomplish and how it can be accessed,” she said.

So the Engage involvement fairsPassport!, West Fest, Taylor Fest and Club Hub are being combined into the Engage! event. that introduce students to organizations on campus will be virtual this year, using a new software platform that lets them immediately interact with the members and advisers, Vogel said.

Other signature events including CultureFest and Sparky’s Day of Service also will be virtual.

“Changemaker wanted to make a strong statement with the residential colleges as partners to make sure we didn’t lose our service commitment,” Vogel said.

“They were able to figure out how they could do meaningful and impactful service online. Some examples include education around literacy and how COVID has exacerbated the conditions contributing to homelessness.”

The virtual Jason Derulo concert in June was such a success that Welcome Week organizers decided to hold the two-hour Infernofest performance remotely as well, she said. That will be from 7 to 9 p.m. Friday, Aug. 21.

“I think it will play out exceedingly well. We’ll see something that continues our tradition but within an engaging virtual space,” Vogel said.

Explore the full list of ASU welcome events.

Top photo by Arizona State University

Mary Beth Faller

Reporter , ASU News