Are the Dyson rings around pulsars detectable? (1705.04142v3)

Abstract: In the previous paper (Osmanov 2016) (henceforth Paper-I) we have extended the idea of Freeman Dyson and have shown that a supercivilization has to use ring-like megastructures around pulsars instead of a spherical shell. In this work we reexamine the same problem in the observational context and we show that facilities of modern IR telescopes (VLTI and WISE) might efficiently monitor the nearby zone of the solar system and search for the IR Dyson-rings up to distances of the order of $0.2$kpc, corresponding to the current highest achievable angular resolution, $0.001$mas. In this case the total number of pulsars in the observationally reachable area is about $64\pm 21$. We show that pulsars from the distance of the order of $\sim 1$kpc are still visible for WISE as point-like sources but in order to confirm that the object is the neutron star, one has to use the UV telescopes, which at this moment cannot provide enough sensitivity.

• The paper establishes that Dyson rings, with habitable zones near 0.1 AU and temperatures around 390 K, could be detected via IR observations.
• It details the use of VLTI and WISE, showing potential detection ranges of up to 0.2 kpc and 1 kpc respectively for resolving these megastructures.
• The study informs SETI strategies by highlighting pulsar vicinities as promising targets for identifying advanced extraterrestrial energy-harvesting constructs.

Detectability of Dyson Rings Around Pulsars: A Review

The paper undertaken by Z. Osmanov investigates the potential detectability of hypothetical Dyson rings constructed by advanced extraterrestrial civilizations around pulsars. This follows an extension of Freeman Dyson's original proposition of reflective shells, suggesting civilizations might construct megastructures to capture significant stellar energy. While Dyson initially focused on spherical shells around stars, Osmanov proposes ring-like structures around pulsars, arguing their feasibility due to reduced material requirements.

Summary of Findings

Osmanov's paper provides a comprehensive analysis of the prospects of detecting such Dyson rings via current observational capabilities, specifically emphasizing infrared (IR) detection methods. Pulsars present a unique energy harnessing opportunity due to their immense rotational energy. By considering slowly rotating neutron stars, with parameters $P=0.5 \, \text{s}$ and $\dot{P} = 10^{-15} \, \text{ss}^{-1}$, the paper establishes that a habitable zone (HZ) can exist at approximately 0.1 AU, where ring temperatures would make them viable candidates for IR observation.

The paper outlines the observational capabilities of instruments like the Very Large Telescope Interferometer (VLTI) and the Wide-field Infrared Survey Explorer (WISE), assessing their suitability for identifying such cosmic constructs. Specifically:

• VLTI: Due to its high angular resolution of $0.001 \, \text{mas}$, the VLTI could potentially resolve Dyson rings at distances up to 0.2 kpc. Within this range, about 64 pulsars might be observed, providing a defined target field for further paper.
• WISE: Although less effective at resolution, WISE's sensitivity is suitable for detecting point-like sources up to 1 kpc. This extends the observational horizon significantly, suggesting up to 1600 pulsars could be potential candidates, albeit without structural detail clarity.

The thermal properties of the rings, estimated to reveal a temperature of about 390 K, suggest visibility in the IR spectrum. Furthermore, the paper discusses UV observations as a means to confirm the presence of neutron stars due to their high surface temperatures (~70,000 K). However, practical UV detections are limited by current sensitivities, making such confirmation challenging at greater distances.

Implications and Future Directions

Osmanov's work challenges researchers to rethink extraterrestrial energy-gathering structures' configurations, focusing on pulsars as a plausible source for such constructs due to their abundance and energy potential. Practically, this exploration informs the development of targeted strategies for SETI (Search for Extraterrestrial Intelligence), prioritizing pulsar vicinities for IR monitoring.

The paper's findings suggest a robust methodology for utilizing existing IR telescopic capabilities to potentially identify extraterrestrial megastructures, providing a framework for future observational missions. While the absence of compelling UV detection capabilities limits immediate multilinear confirmation, advancements in UV telescope sensitivity could provide invaluable complementary data in the future.

Speculations on Future Developments

Looking forward, further advancements in IR observational technologies and methodologies are likely to drive more nuanced investigations into the detectability of Dyson rings. AI and machine learning tools could play a critical role in data analysis and the identification of anomalies suggestive of non-natural structures. Meanwhile, enhancements in UV detection may eventually permit dual-spectrum validation of potential infrared ring observations.

In summary, Osmanov's exploration of Dyson rings around pulsars opens a critical conversation on observational strategies and technological gaps in the search for non-natural cosmic phenomena, underpinning a systematic approach to exploring signatures of advanced extraterrestrial technologies.