相关论文: A Statistical Estimation of the Occurrence of Extr…

Probabilistic arguments about the existence of technological life beyond Earth traditionally refer to the Drake equation to draw possible estimates of the number of technologically advanced civilizations releasing, either intentionally or…

It is shown that, contrary to an existing claim, the near equality between the lifetime of the sun and the timescale of biological evolution on earth does not necessarily imply that extraterrestrial civilizations are exceedingly rare.…

We live in an age where an enormous amount of astrometric, photometric, asteroseismic, and spectroscopic data of Milky Way stars are being acquired, many orders of magnitude larger than about a decade ago. Thanks to the Gaia astrometric…

Giant planets within the habitable zones of the closest several stars can currently be imaged with ground-based telescopes. Within the next decade, the Extremely Large Telescopes (ELTs) will begin to image the habitable zones of a greater…

The primary challenge of rocket propulsion is the burden of needing to accelerate the spacecraft's own fuel, resulting in only a logarithmic gain in maximum speed as propellant is added to the spacecraft. Light sails offer an attractive…

Aims: In this work we aim to investigate the late evolution of ETGs, both observationally and theoretically, by focusing on the stellar mass density profile inside a fixed aperture, within $10 ~\rm{kpc}$ from the galaxy center. Methods: We…

We model the settlement of the galaxy by space-faring civilizations in order to address issues related to the Fermi Paradox. We explore the problem in a way that avoids assumptions about the intent and motivation of any exo-civilization…

Searches for radio technosignatures place constraints on the prevalence of extraterrestrial transmitters in our Galaxy and beyond. It is important to account for the complete stellar population captured within a radio telescope's field of…

I argue that the existence of cold antimatter in bulk is not permitted by the Standard Model, so that if a gamma-ray signature from antiproton annihilation were to be detected, it must represent either new physics or the action of…

Only a handful of gas giant planets orbiting white dwarfs are known. It remains unclear whether this paucity reflects observational challenges or the consequences of stellar evolution. We aim to carry out population synthesis of substellar…

The third EGRET catalog contains a large number of unidentified sources. This subset of objects is expected to include known gamma-ray emitters of Galactic origin such as pulsars and supernova remnants, in addition to an extragalactic…

The all-sky survey in high-energy gamma rays (E$>$30 MeV) carried out by the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma-Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray…

With the start of the Gaia era, the time has come to address the major challenge of deriving the star formation history and evolution of the disk of our MilkyWay. Here we review our present knowledge of the outer regions of the Milky Way…

Artificial general intelligence (AGI) does not yet exist, but given the pace of technological development in artificial intelligence, it is projected to reach human-level intelligence within roughly the next two decades. After that, many…

We analyze the spatial orientation of a homogenous sample of 440 elongated Planetary Nebulae (PNe) in order to determine the orientation of their apparent major axis respect to the Milky Way plane. We present some important geometrical and…

We begin with the premise that the law of entropy could prove to be fundamental for the evolution of intelligent life and the advent of technological civilization. Building on recent theoretical results, we combine a modern approach to…

Vickers et al. (2025) established that 58.20% of astrobiology experts believe intelligent extraterrestrial life likely exists, providing the first empirical baseline for public comparison. We surveyed 6,114 highly educated and…

Microlensing is proving to be one of the best techniques to detect distant, low-mass planets around the most common stars in the Galaxy. In principle, Earth's microlensing signal could offer the chance for other technological civilisations…

We have derived masses and ages for 79 early-type galaxies (ETGs) in different environments at z~1.3 in the Lynx supercluster and in the GOODS/CDF-S field using multiwavelength (0.6-4.5 $\mu$m; KPNO, Palomar, Keck, HST, Spitzer) datasets.…

Using a semi-analytical model of the evolution of the Milky Way, we show how secular evolution can create distinct overdensities in the phase space of various properties (e.g. age vs metallicity or abundance ratios vs age) corresponding to…