Related papers: Research Programs Arising from 'Oumuamua Considere…
1I/'Oumuamua is the first interstellar interloper to be detected, and it shows a non-gravitational acceleration that cannot be accounted for by outgassing, given the strict upper limits of outgassing evident from {\it Spitzer} observations,…
The non-detection of a coma surrounding 1I/`Oumuamua, the first discovered interstellar object (ISO), has prompted a variety of hypotheses to explain its nongravitational acceleration. Given that forthcoming surveys are poised to identify…
In this paper it is presented the concept and design of a new type of spacecraft that could be used to make the first manned interstellar travel. Solar one would integrate three near-term technologies, namely: compact nuclear fusion…
The possibility that extraterrestrial intelligences (ETIs) could be hostile to humanity has been raised as a reason to avoid even trying to contact ETIs. However, there is a distinct shortage of analytical discussion about the risks of an…
In this paper we test the hypothesis that the Pioneer anomaly can be of gravitational origin by comparing the predicted model-independent shifts Delta a/a for the semimajor axis of Uranus and Neptune with the Voyager 2 radio-technical…
We provide a calculation of Pan-STARRS' ability to detect objects similar to the interstellar object 1I/2017 U1 (hereafter 'Oumuamua), including the most detectable approach vectors and the effect of object size on detection efficiency.…
This paper reports the first OH 18-cm line observation of the first detected interstellar object 1I/2017 U1 (`Oumuamua) using the Green Bank Telescope. We have observed the OH lines at 1665.402 MHz, 1667.359, and 1720.53 MHz frequencies…
At this early stage of its passage through our Solar System, 3I/ATLAS, the recently discovered interstellar interloper, has displayed various anomalous characteristics, determined from photometric and astrometric observations. As largely a…
Recently, Anderson et al. presented possible evidence for an anomalous acceleration acting on spacecrafts. Furthermore, the motions of several planets and comets are known to experience unexplained disturbances. A transneptunian comet or…
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…
Human space exploration and settlement of other planets is becoming increasingly technologically feasible, while mission concepts for remote and crewed missions to nearby star systems continue to be developed. But the long-term success of…
In this paper, we investigate the nonprincipal axis (NPA) rotational state of 1I/`Oumuamua -- the first interstellar object discovered traversing the inner Solar System -- from its photometric light curve. Building upon Mashchenko (2019),…
The discovery of 1I/`Oumuamua confirmed that planetesimals must exist in great numbers in interstellar space. Originally generated during planet formation, they are scattered from their original systems and subsequently drift through…
As our ability to undertake more powerful Searches for Extraterrestrial Intelligence (SETI) grows, so does interest in the more controversial endeavour of Messaging Extraterrestrial Intelligence (METI). METI proponents point to the SETI…
The METI risk problem refers to the uncertain outcome of sending transmissions into space with the intention of messaging to extraterrestrial intelligence (METI). Here, I demonstrate that this uncertainty is undecidable by proving that that…
The first discovered interstellar object (ISO), `Oumuamua (1I/2017 U1) shows a dry and rocky surface, an unusually elongated short-to-long axis ratio $c/a \lesssim 1/6$, a low velocity relative to the local standard of rest ($\sim 10$ km…
The twin Pioneer spacecraft have been tracked for over thirty years as they headed out of the solar system. After passing 20 AU from the Sun, both exhibited a systematic error in their trajectories that can be interpreted as a constant…
Analysis of the radio-metric data from Pioneer 10 and 11 spacecrafts has indicated the presence of an unmodeled acceleration starting at 20 AU, which has become known as the Pioneer anomaly. The nature of this acceleration is uncertain. In…
The inverse square law of gravity is poorly probed by experimental tests at distances of ~ 10 AUs. Recent analysis of the trajectory of the Pioneer 10 and 11 spacecraft have shown an unmodeled acceleration directed toward the Sun which was…
We examine the funding disparity in astronomical research priorities: the Habitable Worlds Observatory is planned to receive over $10 billion over the next two decades whereas extraterrestrial intelligence research receives nearly zero…