ASU astronomer finds star fuel surrounding galaxies

January 19, 2022

Most galaxies, including our own, grow by accumulating new material and turning them into stars — that much is known. What has been unknown is where that new material comes from and how it flows into galaxies to create stars.

In a recently published study, Arizona State University astronomer Sanchayeeta Borthakur has identified the faint fuel reservoirs that surround galaxies, and how this fuel can fall into galaxies, allowing them to form new stars and planetary systems. Her research has been published in the American Astronomical Society’s Astrophysical Journal. Illustration of the faint fuel reservoirs that surround galaxies, allowing them to form new stars and planetary systems. Illustration of the faint fuel reservoirs that surround galaxies, allowing them to form new stars and planetary systems. Image by Shireen Dooling/ASU Download Full Image

Previous research in the field of star formation suggested that some galaxies are producing more stars than what their reserve of star-forming gas would allow. This implied to Borthakur, who is an assistant professor at ASU’s School of Earth and Space Exploration, that new gas must be coming into the galaxies and supporting the formation of new stars and planets.

“Observations of galaxies are similar to looking through an airplane window at night and seeing bright city lights surrounded by darkness. Finding this fuel source is like discovering that in the darkness lies the farms and supply routes that support the populations in the cities,” explains Borthakur.

To determine where the gas might be originating, Borthakur used a statistical method known as cross-correlation (to measure the association between two quantities), and data from two publicly available astronomy catalogues: the ALFALFA survey from the Arecibo telescope and the Survey of the Low-Redshift Intergalactic Medium from the Hubble Space Telescope’s Cosmic Origins Spectrograph. With those data, she was able to quantify how gas-rich galaxies are associated with clouds seen in the intergalactic medium.

“It’s like discovering the existence and the location of gas stations in an image of a city full of vehicles,” says Borthakur.

For next steps, she hopes to identify the pathways through which these gas clouds can reach the inner regions of the galaxies where stars are formed.

“Galaxies like ours will continue to grow by forming many more solar systems as new material comes in,” she says. “Understanding the source of the star fuel allows us to predict if new stars will be formed in the future.”

Animation of faint fuel reservoirs surrounding a galaxy, allowing it to form new stars and planetary systems. Credit: Shireen Dooling/ASU

Karin Valentine

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


Cox Collaboratory launches pilot project to help ASU transition to smarter vehicle fleet

January 19, 2022

Last year, the Cox Connected Environments Collaboratory began working with ASU to help the university further its sustainability goal to become "climate positive." This means ASU is working toward a net positive impact, a business approach that allows the university to give back to society, the environment and the economy.

Part of these efforts includes the electrification of ASU’s vehicles and installation of electric charging stations across all university campuses to create a smarter, more sustainable fleet. The Cox Collaboratory is in the process of collecting and verifying data over a six-month period that will provide ASU stakeholders across departments with the information to properly adjust the size of the fleet and placement of charging stations for the all-electric vehicle fleet. ASU pedestrian bridge at night. Download Full Image

“We have hundreds of ASU vehicles in use across our campuses, serving the needs of various departments,” said Alex Kohnen, vice president of Facilities Development and Management at ASU. “By tracking their usage, we can make data-informed decisions to really reduce our fleet to match the needs of the university.”

Leveraging Cox’s network to gather data in real time 

Data collection for the Smart Fleet Data Pilot project began in December 2021 with a fleet of about 500 vehicles — including a mix of SUVs, sedans and carts — that had devices installed to monitor their activity. The Cox Collaboratory used two different technologies for tracking the fleet: Cox’s LoRA (long-range) networks, as well as cellular, for when vehicles traveled outside the reach of the LoRa network.

The vehicles on campus connect using Cox’s LoRA network, which is a long-range, low-power wireless network that offers secure data transmission. This cost-effective solution is ideal for capturing data from vehicles that don’t travel long distances, like the university’s DART carts. The LoRA network’s gateways can be found on the rooftops of three of the tallest buildings around ASU’s Tempe campus. 

Cox Collaboratory Growth Manager Angela Saurini explained that the height of the buildings matters for this type of network, which extends coverage in a circular space downward: “Think of coverage like an open umbrella — the higher the building, the wider our network’s coverage extends,” Saurini said.

To do so, the LoRA network’s gateways each have two, 6-foot antennas that allow the collaboratory to communicate with the devices on the vehicles. A 240-foot cable connects the gateway antennas on the rooftop to the modem inside each building to accommodate for Arizona’s high temperatures. This modem is what provides the wireless internet capability.

A few weeks into the pilot, the Cox team noticed a lag in the connection around the southeastern corner of campus. In response, Saurini set up a smaller, more temporary LoRA gateway (with 2-foot antennae instead of 6-foot) at the University Services Building. This ensures the LoRA network can cover the majority of the Tempe campus. 

And for the vehicles that go beyond the area the three LoRA networks cover, cellular connection is used to monitor the fleet, giving the team an extended range to collect data.

Capturing the right data to inform the future of the fleet 

Because each department utilizes its own fleet of carts, cars and SUVs, it's important for the collaboratory team to gather vehicle activity. The Smart Fleet Data Pilot research team monitors the distances traveled by vehicle type, fuel consumption, greenhouse gas generated, vehicle usage and more. With this information, the team will know the behavior of the vehicles to better inform decision-makers on the types of cars needed and where new electric charging stations should be placed around campus.

“Once we verify the data, we can share the current status of how vehicles are being used,” said Hongbin Yu, an associate professor in ASU’s School of Electrical, Computer and Energy Engineering and the director of the university’s Center for Efficient Vehicles and Sustainable Transportation Systems. “This information is also critical for us to come up with a model or suggestion on how to reduce the fleet and convert (to electric).”

Ideally, Yu says the models will allow the research team to provide quantitative data to key stakeholders of the Smart Fleet initiative to project many different scenarios to develop a strategy. Based on how quickly, aggressively and cost-effectively the university wants to transform the fleet, stakeholders can best determine the next steps for the initiative.

One stopgap in the market, though, is the availability of electric vehicles that best meet ASU’s needs. For example, there aren’t many low-cost SUVs and trucks available on the market. That’s why it’s important to have the data to understand ASU’s usage needs and distance that larger vehicles typically travel.

Although it’s early in the data-gathering process, one finding is already obvious.

“Right away, we’ve noted that a lot of vehicles are not being utilized,” said Yu. “We have seen auto and fuel consumption, but not a lot of miles driven.”

Kohnen mentioned that a benefit of decreasing vehicle density is that it allows the campus to become a safer place.

The importance of partnership to create impact

When it comes to fueling innovation across ASU, partnership is key. Kohnen is excited about the promise this collaborative work brings to the university.

“This pilot is an excellent example of how we can work together to create value for the university, free up resources for our primary mission of educating students and create world-changing research on campus,” said Kohnen.

The Cox Collaboratory team is happy to provide the data needed to help the university make informed decisions as it transitions to an all-electric fleet. 

“We are very intentional in the data that is shared,” said Saurini. “Using Cox’s wireless technology already installed around campus, we are able to provide ASU the data needed to understand the right sizing of the fleet, lower the units of greenhouse gas that are emitted and determine where the charging stations should be placed.”

In turn, the university will be able to leverage this data to be more operationally efficient, support a fleet and migrate to an all-electric fleet.

“It isn’t an individual change that makes an impact,” she added. “But when we come together as an entire university to be more intentional in how we use resources like our vehicles, that is how we can create more sustainable change.” 

Many thanks to our featured interviewees:

Alex Kohnen, Angela Saurini and Hongbin Yu

(From left) Alex Kohnen, Angela Saurini and Hongbin Yu

Stephanie King

Content Strategist, University Technology Office