Interstellar research round-up: power systems, deep-space trajectories and light sails
This round-up from our friends at the Institute for Interstellar Studies (i4is) Educational Academy brings together recent research and commentary on technologies that could support future interstellar exploration, alongside a fresh perspective on the search for extraterrestrial intelligence.
NASA announces NIAC Phase I selections
NASA has announced its 2026 Innovative Advanced Concepts (NIAC) Phase I selections. The programme supports visionary ideas that could transform future space missions through radically improved or entirely new aerospace concepts.[NASA 2026 NIAC]
Among this year’s selections is the plasmon-enhanced radioisotope thermophotovoltaic (PRTPV) generator, proposed by Keunhan Park of the University of Utah, USA. The study will investigate a power system intended to outperform existing radioisotope thermoelectric generators (RTGs) in both efficiency and specific power — the electrical power produced per unit of system mass.
The proposed technology could support missions where solar power is impractical, including long-duration operations in permanently shadowed regions of the Moon and future interstellar spacecraft. These remain research objectives rather than demonstrated capabilities. [NASA PRTPV]
Centauri Dreams explores the Great Filter
Paul Gilster’s Centauri Dreams website has published a thought-provoking essay by Ian Brownlie, “The Ones Who Look Outward”, exploring a possible explanation for the Fermi paradox: why, despite the vast number of potential habitats in the Universe, have we found no confirmed evidence of extraterrestrial civilisations?
Introducing the essay, Gilster asks:
“Thinking about a great filter through which a civilization must pass before its survival is assured usually leads to catastrophic scenarios, such as planetary suicide by nuclear war, or climate holocaust (assuming the filter lies ahead of us and not behind). But filters may be more subtle and tied in with epistemology. How does intelligence view its place in the universe and thereby engage with other beings?”
Brownlie considers whether the challenge lies not simply in developing intelligence, but in sustaining outward-looking scientific enquiry across generations. His essay suggests that preserving and building on knowledge long enough to achieve a durable spacefaring civilisation may itself be a rare and fragile accomplishment. [centauri-dreams]
High-temperature photovoltaics for solar-electric Oberth manoeuvres
Nadim Maraqten and colleagues have uploaded a paper examining how high-temperature solar cells could support solar-electric Oberth manoeuvres, potentially enabling substantial payloads to reach the distant Solar System within a few decades.
The Oberth effect allows a spacecraft to gain more orbital energy from a given change in velocity when thrust is applied at high speed, deep within a gravitational well. The proposed approach concentrates electric propulsion near a close solar passage, at a perihelion of 0.3 astronomical units (AU). Motivated by laboratory demonstrations of solar cells operating near 400°C, the authors investigate how high-intensity, high-temperature photovoltaics might make such a manoeuvre practical.
Under the study’s assumptions, trajectory optimisation indicates that an expendable Falcon Heavy could deliver tonne-class payloads to 200 AU within 25 years. With a Jupiter gravity assist, this would require power-system specific power around 10% above present-day conventional levels; a direct trajectory would require approximately twice those levels.
The authors calculate a threefold increase in specific orbital energy for the same change in velocity compared with a spiral trajectory starting at 1 AU. Their results suggest that high-temperature photovoltaics could become an enabling technology for high-energy deep-space missions, rather than simply a means of surviving close to the Sun. The work is presented as an arXiv preprint. [arxiv]
A new approach to light sails
An article by Melissa Pappas on the University of Pennsylvania’s engineering website highlights research into ultralight materials for laser-driven light sails. The work, led by Matthew F. Campbell and colleagues and published in Nature Communications, reports an experimental demonstration of corrugated nanolaminate films designed to combine low mass, reflectivity and mechanical strength.[engineering.upenn]
The prototype sails use molybdenum disulfide sandwiched between layers of alumina, with microscopic hexagonal corrugations providing strength and flexibility without substantially increasing their weight. They were fabricated using scalable semiconductor-processing techniques.
Laboratory measurements showed an areal density below one gram per square metre, reflectivity above 50% and absorption below 4%. The uncertainty in the absorption measurements leaves open the possibility of substantially lower absorption — an important consideration for sails exposed to intense laser illumination.
The prototypes are only around three millimetres across, and major challenges remain, including reducing absorption further, scaling up the sails and developing the laser infrastructure needed to propel them. Nevertheless, the work represents a promising experimental step towards laser-driven interstellar propulsion, with potential applications elsewhere in space technology.View the paper here: [https://www.nature.com/articles/s41467-026-73414-4.]