Ultraviolet shines light on origins of the solar system


October 16, 2020

In the search to discover the origins of our solar system, an international team of researchers, including planetary scientist and cosmochemist James Lyons of Arizona State University, has compared the composition of the sun to the composition of the most ancient materials that formed in our solar system: refractory inclusions in unmetamorphosed meteorites.

By analyzing the oxygen isotopes (varieties of an element that have some extra neutrons) of these refractory inclusions, the research team has determined that the differences in composition between the sun, planets and other solar system materials were inherited from the protosolar molecular cloud that existed even before the solar system. The results of their study have been recently published in Science Advances. The Butterfly nebula, an example of a star-forming region. A bright central star, obscured by dust, modifies the oxygen isotopes in the nebula by photodissociation of carbon monoxide. This is an example of an environment in which oxygen isotopes could be modified in the molecular cloud prior to formation of a planetary system. Credit: NASA and ESA Download Full Image

“It has been recently demonstrated that variations in isotopic compositions of many elements in our solar system were inherited from the protosolar molecular cloud,” said lead author Alexander Krot, of the University of Hawaii. “Our study reveals that oxygen is not the exception.”

Molecular cloud or solar nebula?

When scientists compare oxygen isotopes 16, 17 and 18, they observe significant differences between the Earth and the sun. This is believed to be due to processing by ultraviolet light of carbon monoxide, which is broken apart leading to a large change in oxygen isotope ratios in water. The planets are formed from dust that inherits the changed oxygen isotope ratios through interactions with water.

What scientists have not known is whether the ultraviolet processing occurred in the parent molecular cloud that collapsed to form the proto-solar system or later in the cloud of gas and dust from which the planets formed, called the solar nebula.

A star-forming region in NGC 3324 in the Carina nebula. Neighboring large stars both sculpt the shape of the nebula and alter the distribution of oxygen isotopes by the photodissociation of carbon monoxide by ultraviolet light. The results of the work presented here favor alteration of oxygen isotopes in a molecular cloud environment (white scale bar is 5 light years or 300,000 AU). Image credit: NASA, ESA, Hubble Heritage Team

To determine this, the research team turned to the most ancient component of meteorites, called calcium-aluminum inclusions (CAIs). They used an ion microprobe, electron backscatter images and X-ray elemental analyses at the University of Hawaii’s Institute of Geophysics and Planetology to carefully analyze the CAIs. They then incorporated a second isotope system (aluminum and magnesium isotopes) to constrain the age of the CAIs, making the connection — for the first time — between oxygen isotope abundances and mass 26 aluminum isotopes.

From these aluminum and magnesium isotopes, they concluded that the CAIs were formed about 10,000 to 20,000 years after the collapse of the parent molecular cloud.

“This is extremely early in the history of the solar system,” said Lyons, who is an associate research professor at ASU’s School of Earth and Space Exploration, “so early that there would not be enough time to alter oxygen isotopes in the solar nebula.”

Although more measurements and modeling work are needed to fully assess the implications of these findings, they do have implications for the inventory of organic compounds available during solar system and later planet and asteroid formation.

“Any constraint on the amount of ultraviolet processing of material in the solar nebula or parent molecular cloud is essential for understanding the inventory of organic compounds that lead to life on Earth,” Lyons said.

Karin Valentine

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

480-965-9345

 
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Pandemic underscores resiliency benefit of having a college degree

October 16, 2020

ASU white paper quantifies benefits of people who earn degree through Starbucks College Achievement Plan

As the coronavirus pandemic upends the economy, one group of workers has suffered fewer job losses and rebounded faster — those with a bachelor’s degree. 

Data from the U.S. Department of Labor Statistics show that when pandemic-related unemployment peaked in April, people who have earned a four-year degree had an unemployment rate of about 8%, which then dropped to 4% in September.

Meanwhile, people with only a high school diploma had a 17% unemployment rate in April, dropping to 9% in September. Those with some college but no degree went from 15% unemployment in April to 8% in September.

Arizona State University President Michael Crow pointed out the employment statistics and reiterated the value of a college education in a recent letter to stakeholders.

“Higher levels of education enhance the ability of workers to participate in and experience growth from the innovative business practices developed during times of massive social and economic change,” he wrote.

“Increased access to high-quality education provides benefits of consequence at every level: individual, community, state and society.”

While the pandemic is an unforeseen shock to the economy, the trend mirrors previous economic downturns. People with a bachelor’s degree fared better during the peak months of the economic recession, with nationwide unemployment for them hovering around 5% during 2009 and 2010. Unemployment rates for people with only a high school diploma hit about 10% during that time, while those with some college but no bachelor’s degree had unemployment rates of around 8%.

And degree holders have more than a sturdier job outlook. Economists have long been able to objectively measure the value of a college degree in variables such as increased lifetime salary, better health and even a higher likelihood of volunteering.

U.S. Census data show the average 2019 salaries for educational attainment:

  • Attended high school but did not earn a diploma: $29,082.
  • High school graduate: $39,371.
  • Some college but no degree: $42,808.
  • Associate degree: $48,687.
  • Bachelor’s degree: $73,163.
  • Master’s degree: $93,092.
  • Doctorate: $140,337.
  • Professional degree: $152,703.

Last year, three ASU economists produced a white paper that quantifies the benefits of people who earn a college degree through the Starbucks College Achievement Plan. Since 2014, more than 4,700 Starbucks employees, called partners, have earned degrees through ASU Online, getting reimbursed for their tuition every semester.

The three authors are Kent Hill, research professor and principal research economist in the Seidman Research Institute at ASU; Dennis Hoffman, professor of economics who serves as the university economist and director of the Seidman Research Institute; and Tom Rex, associate director of the Center for Competitiveness and Prosperity Research at ASU and manager of research initiatives in the Office of the University Economist at ASU.

 Their calculations showed:

  • The net lifetime benefit in cost savings and enhanced earnings for a Starbucks partner who entered the Starbucks College Achievement Plan at age 18 is about $500,500. Those who started at an older age would have a lower lifetime benefit because they have fewer working years after the degree is earned.
  • People who earn a degree through the program avoid up to $12,000 in student loan interest. 
  • Assuming there are 25,000 graduates of the program by 2025, the benefit to society in increased tax revenue would be $2.1 billion. If you assume that one-third of those graduates would have earned a degree even without the Starbucks program, the increased tax revenue would be $1.4 billion.

For one ASU student, the pandemic has brought challenges but also a renewed sense of the importance of working toward a degree.

Najja Meeks

“There’s no reason to stop your momentum,” said Najja Meeks, a Los Angeles resident who has been pursuing a degree in organizational leadership through the Starbucks College Achievement Plan since 2018.

“If someone has been laid off or their industry is something that is going to be affected once the pandemic is over, this is a great opportunity to consider making a pivot in their career and learning new skills.”

Meeks was a stay-at-home mom when she began working at Starbucks. She used to open the store every day with a co-worker who was in the Starbucks College Achievement Plan. 

“I heard a lot about his frustrations and triumphs,” she said. “And I thought, ‘When else will I go to school?’ I wanted something more for my family.”

Meeks, who had been away from college for 10 years, started classes in fall 2018, going straight through summers. When the pandemic hit, her store closed and she moved to a drive-thru location. But her work hours increased at the same time her three children were at home more. So she made the tough decision to withdraw from a class.

“A lot of things had changed in my life and I thought I would save myself some sanity, even though I knew doing so would add time to completing my degree,” said Meeks, who also decided to add a focus in project management to her degree program.

While learning online was new to Meeks when she started her degree through ASU Online, her experience with it has become an asset. 

“My children are also doing online learning, so being an online student myself really helped me to help them accept their new class life,” she said. “It gave me a lot more patience.”

Meeks expects to graduate in 2021 and is anticipating a career in project management or human resources. She’s confident even as the economic outlook is uncertain. 

“Before I started at ASU and before I had children, I was in a different field. I used to be an actor,” she said.

“I never saw myself pursuing this type of degree, but as you get older, your priorities and your interests shift.”

Top photo: Susana Monica (right) and Kelsey Laubie stand to be recognized as Starbucks scholars during the College of Health Solutions convocation at Wells Fargo Arena on May 12, 2017. Photo by Deanna Dent/ASUNow

Mary Beth Faller

Reporter , ASU Now

480-727-4503