Florida-based Space Beyond plans to start building its first memorial spacecraft next week after booking a launch on SpaceX’s October 2027 rideshare mission.
In this episode ofPhysics World Stories, host Andrew Glester explores the fascinating hunt for pristine comets – icy bodies that preserve material from the solar system’s beginnings and even earlier. Unlike more familiar comets that repeatedly swing close to the Sun and transform, these frozen relics act as time capsules, offering unique insights into our cosmic history.
Interstellar comet 3I/ATLAS is seen in this composite image captured on 6 November 2025 by the Europa Ultraviolet Spectrograph instrument on NASA’s Europa Clipper spacecraft. (Courtesy: NASA/JPL-Caltech/SWRI)
The first guest is Tracy Becker, deputy principal investigator for the Ultraviolet Spectrograph on NASA’s Europa Clipper mission. Becker describes how the Jupiter-bound spacecraft recently turned its gaze to 3I/ATLAS, an interstellar visitor that appeared last July. Mission scientists quickly reacted to this unique opportunity, which also enabled them to test the mission’s instruments before it arrives at the icy world of Europa.
Michael Küppers then introduces the upcoming Comet Interceptor mission, set for launch in 2029. This joint ESA–JAXA mission will “park” in space until a suitable comet arrives from the outer reaches of the solar system. They will deploy two probes to study it from multiple angles – offering a first-ever close look at material untouched since the solar system’s birth.
From interstellar wanderers to carefully orchestrated intercepts, this episode blends pioneering missions and cosmic detective work. Keep up to date with all the latest space and astronomy developments in the dedicated section of the Physics World website.
Europe stands on the precipice of launching a satellite from the mainland. Until now, the Guiana Space Centre in South America has operated as Europe’s “gateway to space” but spaceports in SaxaVord and Andøya offer the tantalizing prospect of launches much closer to home. Yet infrastructure alone will not get us there. A launchpad is […]
With the fiscal year 2026 appropriations process effectively complete, a key House appropriator says the next spending bill for NASA should build on that outcome.
As with people, age in cosmology does not always extrapolate. An early-career politician may be more likely to win a debate with a student than with a seasoned diplomat, but put all three in a room with a toddler and the toddler will almost certainly get their own way – they are following a different set of rules. A team of global collaborators noticed a similar phenomenon when peering at a cluster of developing galaxies from a time when the universe was just a tenth of its current age.
Cosmological theories suggest that such infant clusters should host much cooler and less abundant gas than more mature clusters. But what the researchers saw was at least five times hotter than expected – apparently not abiding by those rules.
“That’s a massive surprise and forces us to rethink how large structures actually form and evolve in the universe,” says first author Dazhi Zhou, a PhD candidate at the University of British Columbia.
Eyes on the past
Looking into distant outer space allows us to peer into the past. The protocluster of developing galaxies that Zhou and collaborators investigated – known as SPT2349–56 – is 12.4 billion light years away, so the light observed from it left home when the universe was just 1.4 billion years old. Light from so far away will be quite faint and hard to detect by the time it reaches us, so the researchers used the Atacama Large Millimeter/submillimeter Array (ALMA) to study SPT2349–56 using a special type of shadow.
As this type of protocluster develops, Zhou explains, the gas around its galaxies becomes so hot that electrons in the gas interact with, and confer some of their energy upon, passing photons. This leaves light passing through the gas with more photons at the higher energy end of the spectrum and fewer at the lower end. When viewing the cosmic microwave background radiation – the “afterglow” left behind by the Big Bang – this results in a shadow at low energies. This energy shift, discovered by physicists Rashid Sunyaev and Yakov Zeldovich, not only reveals the presence of the protocluster, but the strength of this signature indicates the thermal energy of the gas in the protocluster.
The team’s observations were not easy. “This shadow is actually pretty tiny,” Zhou explains. In addition, there is thermal emission from the dust inside galaxies at radio wavelengths, originally estimated to be 20 times stronger than the Sunyaev–Zeldovich signature. “It really is like finding a needle in a haystack,” he adds. Nonetheless, the team did identify a definite Sunyaev–Zeldovich signature from SPT2349–56, with a thermal energy indicating that it was at least five times hotter than expected – thousands of times hotter than the surface of our Sun.
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SPT2349–56 has some quirks that may explain its high thermal energy, including three supermassive black holes shooting out jets of high-energy matter – a known but rare phenomenon for these supermassive black holes. However, simulations that take these outbursts into account as a heating mechanism that’s more efficient and occurs much earlier than heating from gravitational collapse (as current models suggest) still do not give the high temperatures observed, perhaps pointing to gaps in our knowledge of the underlying physics.
Eiichiro Komatsu from the Max-Planck-Institut für Astrophysik describes the work as “a wonderful measurement”. Although not directly involved in this research, Komatsu has also looked at what the Sunyaev–Zeldovich effect can reveal about the cosmos. “The amount of thermal energy measured by the authors is staggering, yet its origin is a mystery,” he tells Physics World. He suggests these results will motivate further observations of other systems in the early universe.
“We need to be cautious rather than making any big claim,” adds Zhou. This is the first Sunyaev–Zeldovich detection of a protocluster from the first three billion years of the universe’s existence. Next, he aims to study similar protoclusters, and he hopes others will also work to corroborate the observations.
Learn more about the oldest rock art on record, a stencil of a human hand in Indonesia, which reveals important insights into the movement of humans into Australia.
China’s damaged Shenzhou-20 spacecraft returned safely to Earth after on-orbit internal repairs, concluding the country’s first human spaceflight emergency triggered by a suspected debris impact.
Learn how chemicals released by gut microbes end up in exhaled breath, and how researchers used those signals to identify microbial communities linked to disease.
Learn more about ancient giant kangaroos and the previous research claiming they were too heavy to hop. A new study finds that hopping may have been one of the few movement methods for these ancient animals.
Open Cosmos deployed two satellites Jan. 22 to activate Ka-band spectrum filings reassigned by Liechtenstein last week, racing to meet deployment deadlines to bring the frequencies into use for sovereign and enterprise broadband.
Blue Origin launched its first New Shepard mission of the year Jan. 22, carrying five paying customers and one company employee after a last-minute change.
Gen. Shawn Bratton, vice chief of space operations of the U.S. Space Force, says growing reliance on satellites is forcing faster integration with the joint force and long-term planning beyond Earth orbit
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