Collecting Data for NASA

Early Thursday morning, NASA's Orion spacecraft, carrying four astronauts, launched toward the Moon. It is NASA’s first crewed lunar mission since the Apollo program ended in 1972 and serves as a test run for a potential future mission to Mars.

But that’s not all: NASA is, among other things, also using Orion to determine whether commercial providers, universities and individuals could assist the space agency with tracking satellites and spacecraft in the future. To do so, it has launched a global call to collect data on the mission’s trajectory from various sources.

The Department of Physics at the University of Zurich (UZH) is one of 34 institutions from around the world selected by NASA for this test run. Achim Vollhardt, an instructor at the Department of Physics and head of the UZH electronics workshop, submitted UZH’s application to the program. He was also behind the installation of a radio telescope on the roof of the physics building at Irchel Campus last year. “To give students the opportunity to work with real data in a hands-on way,” he explains.

Once the Orion spacecraft reaches a certain distance from Earth, it will be visible to the radio telescope at Irchel. In this case, “visible” means the antenna is able receive the radio waves the capsule sends back to Earth. Orion remains within the antenna’s range for approximately five hours per day. During this time, Vollhardt collects data.

Although the antenna can only receive signals from the spacecraft along a portion of its trajectory, it is possible to calculate the entire trajectory based on this data. “It’s not exactly straightforward,” says Vollhardt. “But since we know the positions of the Sun, Moon and Earth, we can calculate the trajectory accurately using Newtonian celestial mechanics.”

Vollhardt plans to do just that with his students, among other things, for example calculating the impact of changing various parameters, such as Orion’s altitude as it flies around the Moon. “What happens if you change parameters: the capsule would not return to Earth.” This clearly demonstrates how precisely the entire trajectory must be balanced. “This means we will be able to measure and track some trajectory corrections during the mission,” says Vollhardt.

The raw data must be filtered and then processed before it is sent to NASA. “The students will be directly involved in this step,” Vollhardt explains. He has come up with several Bachelor’s papers for students to write on this topic. Among other things, noise must be removed from the data and they need to be saved in a specific format.

NASA is not actively using the data for its current mission. Instead, the aim is to determine whether private, and potentially commercial, providers can support NASA in its future missions to the Moon and Mars. The deputy coordinator of NASA’s Space Communication and Navigation program was cited as saying, “This is about building a resilient, public-private ecosystem,” in a communication. 

Achim Vollhardt’s participation in NASA’s call was no coincidence. A specific range of radio wave frequency is reserved for space travel. “Our antenna is specifically tuned to this frequency range, allowing us to track uncrewed spacecraft, such as satellites,” Vollhardt explains. Space travel continues to capture our imaginations: “Some students are really enthusiastic about it. The idea was to get them involved by appealing to this interest.” However, what he didn’t know is that NASA was seeking partners for a crewed mission.

Even when the antenna is not pointed directly at the Orion capsule, Vollhardt can use it to measure a wide variety of other data, including information from weather satellites and radio waves emitted by the Sun. This allows us to observe how solar activity is changing in this regard.

Vollhardt received financial support for the antenna as part of the Schools at Irchel project. This allows students from Kantonsschule Zürich Nord, the high school that is currently housed opposite the Department of Physics at Irchel Campus, to use the antenna, giving them the chance to learn about physical phenomena, such as the Doppler effect, and the mechanics of celestial bodies. For Vollhardt, there’s no doubt that, “it’s much more exciting when you’re watching live and following real data.”