The Odyssey lander that crashed on the Moon last year benefited radio astronomy before it died

The prestigious astronomical journal The Astrophysical Journal recently published an article that highlighted a literal scientific feat accomplished by the dying Nova-C Odyssey lander on the Moon from Intuitive Machines. One of the scientific instruments on the module collected enough data to test the operation of a real radio telescope on the satellite, which became the world’s first example of alien astronomical observation.

A visual look at the Odyssey lunar landing. Image source: Intuitive Machines

The hero of the article is the NASA ROLSES-1 instrument, a low-frequency radio spectrograph designed to study the “density and height of the photoelectron shell near the lunar surface.” In essence, it is a radio telescope, which became the first experiment in radio astronomy conducted on the Moon. The device was equipped with four short antennas designed to capture radio waves of certain frequencies near the surface of the Moon. Its data will help assess the prospects for building a full-fledged radio telescope for astronomical observations on the satellite.

On Earth, radio astronomy is increasingly suffering from man-made interference. The greatest threat to science comes from Internet satellites and direct connection systems to smartphones. Telecommunication systems in low Earth orbit can literally destroy terrestrial radio astronomy. Therefore, scientists are considering the possibility of deploying radio telescopes on the Moon, especially on its far side, which is most protected from interference. The ROLSES-1 experiment was supposed to collect information on the influence of the lunar surface on radio waves in the ranges of the main hydrogen line and the cosmic background. The emergency landing of the module did not interfere with the experiment.

The Unruly Antenna

It’s funny, but one of the four antennas of the ROLSES-1 complex deployed while still approaching the Moon. This random event helped collect data on interference from terrestrial radio sources. The device recorded active radio interference from terrestrial radio stations and signals from satellites in near-Earth orbit. On the day the antenna began collecting data, the entire North American continent was on the “radar”. Thus, scientists were able to look at the Earth through the eyes of alien observers, trying to assess the technosignatures of civilization. It was important to conduct these measurements taking into account the influence of the planet’s ionosphere on radio signals.

The device collected data for several hours as it approached the Moon and was turned on twice on its surface while the batteries of the module that had made an emergency landing still had power. In total, it worked on the Moon for 20 minutes, although the scientific program was originally designed for eight days.

Orientation of the Earth at the moments of the instrument operation

«“All is not lost,” said study co-author and ROLSES-1 project scientist Jack Burns at the 224th meeting of the American Astronomical Society in June 2024. “We have a good [frequency] image of Earth from a unique vantage point.”

The data collected by ROLSES-1 will help improve the ROLSES-2 (2027) and LuSEE-Night (2026) experiments. The latter will be sent to the far side of the Moon. All of these projects will lay the foundation for building a full-fledged radio astronomy observatory on the satellite by the late 2030s or early 2040s. And although the Odyssey landing was a bit of a flop (the Athena mission also failed this year), scientists were able to obtain data for the next step forward.