Underwater telescope tests Einstein's laws using neutrino analysis

The NASA Swift space telescope concluded its journey of more than twenty years in space this Wednesday (4). The observatory reentered the Earth's atmosphere uncontrollably, three months after a rescue attempt by a private company failed.

Officially named the Neil Gehrels Swift Observatory, the instrument was placed into orbit in November 2004 with the purpose of investigating gamma-ray bursts, considered some of the most powerful events in the Universe.

According to data reported by Space.com, the telescope crossed the atmosphere at 9:39 AM (Brasília time) over northern Sumatra, Indonesia. The equipment weighed approximately 1,450 kg and its dimensions were comparable to a microbus.

Most of the structure was expected to disintegrate during atmospheric passage. Before re-entry, NASA calculated that the probability of any surviving fragment hitting someone on the Earth's surface was only one in 2,100.

The return to Earth could have been postponed. In September 2025, NASA signed a contract worth $30 million (equivalent to about R$165 million) with the American company Katalyst Space to develop a robotic mission aimed at raising Swift's orbit.

The observatory was progressively losing altitude due to atmospheric drag and did not have its own thrusters to counteract this effect.

To execute the rescue, the company created LINK, a robotic spacecraft equipped with three arms and similar in size to a refrigerator. This equipment was launched on July 3, 2026, aiming to reach Swift in August.

However, the operation did not proceed as planned. LINK faced issues with its propulsion system and the reaction wheels responsible for maintaining its spatial orientation, which made meeting the telescope impossible. The rescue spacecraft itself ended up returning to Earth on September 25.

Despite the failure of the rescue mission, NASA assessed that the initiative provided valuable knowledge for future satellite maintenance and life extension operations.

The end of the Swift mission is not an isolated event. A 2025 report cited by Space.com indicates that, on average, at least three large objects—whether decommissioned satellites or rocket parts—reenter the Earth's atmosphere daily.

This number is projected to increase in the coming years as humanity increases the number of satellites in orbit, especially through mega-constellations. Thus, the end of the Swift mission also highlights a growing challenge for space exploration: managing the ever-increasing amount of orbital equipment and planning the fate of these structures when they cease to operate.

Francis Halzen, a naturalized American and Belgian citizen, was awarded the 2026 Nobel Prize in Physics for his fundamental work in the development of IceCube. This observatory is located deep within the ice at the South Pole in Antarctica and has the capability to identify high-energy neutrinos, providing new information about the most extreme environments in the Universe.

The topic was discussed on the Space View program this Friday (30), where physicist Alexandre Cherman participated to detail how IceCube aids in investigating the most intense cosmic phenomena and what neutrinos can reveal about them. Cherman, who is an astronomer, holds a PhD in theoretical physics, is a data scientist, educator, speaker, and author of eight books, and is also a co-author of the educational game Cosmic Real Estate, produced by Estrela Cultural. He currently leads the Astronomy department at the Rio de Janeiro City Planetarium Foundation.

The concept of using Antarctic ice as a particle detector dates back to 1988. After more than twenty years of development, IceCube began operating in 2010. Its structure covers about one cubic kilometer of ice and is composed of 5,160 optical sensors distributed across 86 vertical cables extending between 1.45 and 2.45 kilometers in depth.

Neutrinos are subatomic particles that have no electric charge and possess very little mass. Generated in various natural events, they can pass through celestial bodies, such as planets and stars, and even the human body, interacting minimally with matter. It is estimated that approximately one hundred trillion of these neutrinos pass through a person every second.

The detection of these neutrinos occurs when they collide with an atom present in the ice, generating charged particles. These, in turn, emit a brief bluish glow known as Cherenkov radiation. The sensors capture these signals, allowing researchers to calculate the energy and determine the direction of the particle's origin.

Unlike conventional telescopes, which function by capturing light, IceCube focuses on observing particles. Due to the lack of electric charge in neutrinos, their paths are not altered by magnetic fields. This allows them to point towards the location of cosmic accelerators, meaning extreme environments capable of generating particles with energies far exceeding those achieved in terrestrial laboratories.

The discoveries made by the observatory have boosted the field of neutrino astronomy, which complements observations made with light and gravitational waves. IceCube remains operational and is receiving continuous improvements to increase its detection capacity, identify new sources of these particles, and aid in understanding the most extreme phenomena in the Universe.

Marcelo Zurita, president of the Paraíba Astronomy Association – APA, a member of the SAB – Brazilian Astronomical Society, technical director of the Brazilian Meteor Observation Network (Bramon), and national coordinator of Asteroid Day Brazil, presents the program, which is broadcast live every Friday at 9 PM (Brasília time) on the official channels of the outlet on YouTube, Facebook, Instagram, X (formerly Twitter), LinkedIn, and TikTok. The original content was published on Olhar Digital.

NASA has formally ended the mission of the Swift space telescope after a rescue attempt was unsuccessful. This observatory, which dedicated more than two decades to studying the Universe, is in the process of losing altitude and is expected to re-enter Earth's atmosphere in the coming weeks.

The rescue operation was conducted by Katalyst Space Technologies, a company based in Arizona, United States. This company developed the spacecraft named LINK with the purpose of reaching the telescope and elevating it to a higher orbit, enabling the continuation of its scientific investigations.

However, the initiative was not successful. Approximately three weeks after its launch, on July 3rd, the LINK spacecraft encountered problems with its propulsion system and the reaction wheels responsible for maintaining its orientation. These failures caused the spacecraft to spin at an unexpected speed, which made capturing and elevating Swift impossible.

Despite the setbacks, LINK managed to approach the observatory and take photographs of it. The separation between the two spacecraft varied between 12 and 15 kilometers, which proved insufficient to complete the planned operation.

Swift was losing altitude due to atmospheric drag and does not have adequate thrusters to neutralize this effect. In September 2025, NASA awarded Katalyst a contract worth US$ 30 million (equivalent to about R$ 162 million) to attempt to save the observatory.

The adopted strategy involved a spacecraft comparable in size to a refrigerator, equipped with three robotic arms. The concept was for LINK to reach Swift, capture it, and guide it to a higher orbit. This mission was pioneering, as no private spacecraft had managed to capture and elevate a satellite that was not designed to receive such maintenance. Speed was also crucial, given that Swift continued to lose altitude while the operation preparation proceeded.

Although the attempt failed to extend the telescope's lifespan, NASA considered the project valuable for fostering the development of robotic maintenance technologies in space and for testing the capacity to execute operations of this magnitude in short periods.

Swift was officially named the Neil Gehrels Swift Observatory in 2018, in memory of its first principal investigator, who passed away the previous year. With the end of the mission, the observatory will return to Earth's atmosphere in the coming weeks, but the collected data will remain accessible for future scientific research.