On Sunday, March 2, at 2:30 am, a team of researchers gathered in a lab in Boston University’s College of Engineering. It was a moment they had anticipated for years: a BU-developed telescope, called the Lunar Environment heliospheric X-ray Imager (LEXI), was moments from touching down on the surface of the moon. The telescope is attached to NASA’s Blue Ghost Mission 1 spacecraft, which blasted off from Florida on January 15. 

As the lunar lander got closer and closer to the surface, lead LEXI scientist Brian Walsh, an ENG associate professor of mechanical engineering, read the craft’s elevation above the moon surface aloud to the room of a dozen team members. NASA’s live broadcast of the landing was on a screen in the background. When the elevation reached zero, the room quieted.

Then, a voice from Blue Ghost’s central communications team announced that the spacecraft had successfully landed on the moon. Walsh and the whole team clapped and cheered. 

“The team is thrilled to reach this milestone,” says Walsh (GRS’09,’12). 

After a quick celebration, they were back to business.

See the BU team’s reaction when Blue Ghost—carrying the LEXI telescope they designed and built—successfully landed on the moon. Video by Devin Hahn

“We’re staying focused on the end goal, capturing first-of-its-kind images of Earth’s magnetic field,” Walsh says. 

On its journey to the moon, the Blue Ghost spacecraft—designed by private company Firefly Aerospace and commissioned by NASA—captured stunning images of Earth from space. Now having landed, LEXI will send X-ray emission data back to BU, which Walsh and his team will use to advance our understanding of Earth’s protective magnetic shield. 

After touching down in a flat region of the moon, called Mare Crisium, Firefly began gradually powering up various parts of the lander, which has 10 payloads, including LEXI. By 6:47 am, LEXI was ready to go. Walsh and the team triggered a latch that opened a small door on the front of the telescope, exposing LEXI’s lenses to the expanse of space for the first time.

Blue Ghost’s antenna (left) is deployed. Shortly after touching down, the lander’s payloads—including LEXI, which juts out on the right side of the spacecraft—were gradually powered up. Once powered, the telescope’s lenses opened to receive data. Video loop courtesy of Firefly Aerospace

The instrument’s specially designed optics will capture the first-ever images of a huge swath of Earth’s space environment, recording X-rays released when particles emanating from the sun collide with atoms floating around our outermost atmosphere. The data is essential for understanding the relationship between Earth’s magnetic field and the sun’s solar wind. 

Walsh and the team, including members that have been with the project since it started in 2019, will be working 24-hour shifts for the next week from their mission control hub in BU’s Photonics Center. According to Ramiz A. Qudsi, a BU Center for Space Physics research scientist and lead data scientist for LEXI, the data needs to be analyzed in real time to ensure it’s healthy and recording at the expected rate. Qudsi helped develop LEXI’s software.

After about a week of data collection, the sun will set on the moon (one moon day is about 27 Earth days) and icy temperatures—dipping as low as -208 degrees Fahrenheit—will disable the lander and all of its payloads permanently. 

“We get such a precious, small amount of time to conduct this experiment,” Walsh says. The team—which has collaborated closely with colleagues at NASA Goddard Space Flight Center and Johns Hopkins University—will be hard at work for the entirety of LEXI’s lifespan on the lunar surface. 

As the mission continues, The Brink will monitor LEXI’s progress. Follow BU on social media and check back on The Brink for more exciting updates and images—like those below captured by Blue Ghost on its journey to the moon, and from the lunar surface. To learn more about the years of work that went into creating LEXI and the science it will perform on the moon, and to watch videos of the telescope coming together, check out our mission countdown.