Related papers: The Brute-Force Search for Planet Nine
The anomalous orbits of trans-Neptunian objects can be accounted for by the planet 9 hypothesis. One intriguing possibility is that planet 9 could be a dilute axion star captured by the solar system, with the ratio of the axion star to dark…
Experience in exploring our own solar system has shown that direct investigation of planetary bodies using space probes invariably yields scientific knowledge not otherwise obtainable. In the case of exoplanets, such direct investigation…
(Abridged) The solar system gas giant planets are oblate due to their rapid rotation. A measurement of the planet's projected oblateness would constrain the planet's rotational period. Planets that are synchronously rotating with their…
We speculate on the development and availability of new innovative propulsion techniques in the 2040s, that will allow us to fly a spacecraft outside the Solar System (at 150 AU and more) in a reasonable amount of time, in order to directly…
The growing rate of increase in the number of the discovered extra-solar planets which has consequently raised the enthusiasm to explore the universe in hope of finding earth-like planets has resulted in the wide use of Gravitational…
Motivated by recent measurements of the free-floating planet mass function at terrestrial masses, we consider the possibility that the solar system may have captured a terrestrial planet early in its history. We show that $\sim 1.2$…
The trans-Neptunian region of the solar system exhibits an intricate dynamical structure, much of which can be explained by an instability-driven orbital history of the giant planets. However, the origins of a highly inclined, and in…
Microlensing has recently proven to be a valuable tool to search for extrasolar planets of Neptune- to super-Earth-mass planets at orbits of few AU. Since planetary signals are of very short duration, an intense and continuous monitoring is…
Studies of the clustering of the most distant Kuiper belt objects in the outer solar system have hinted at the possible existence of a planet beyond Neptune referred to as Planet Nine (P9). Recent efforts have constrained the parameter…
Beyond black holes and neutron stars, new hypothetical compact objects have been proposed as potential astrophysical entities. In general, their properties have not yet been fully explored or understood, nor has it been proven whether or…
To explain the unusual distribution of Kuiper Belt objects, several authors have advocated the existence of a super-Earth planet in the outer solar system. It has recently been proposed that a 10 M$_{\oplus}$ object with an orbit of 700 AU…
Large scale imaging surveys will increase the number of galaxy-scale strong lensing candidates by maybe three orders of magnitudes beyond the number known today. Finding these rare objects will require picking them out of at least tens of…
Earth-like extra-solar planets may be detected with 1-2m class telescopes using the gravitational microlensing technique. The essential requirement is the ability to be able to carry out continuous observations of the galactic bulge. A…
The primary difficulty with using transits to discover extrasolar planets is the low probability a planet has of transiting its parent star. One way of overcoming this difficulty is to search for transits in dense stellar fields, such as…
It has been suggested that a gravitational slingshot from the hypothetical Planet 9 (P9) could explain the unusually large velocity of meteor CNEOS 2014-01-08. I show that this explanation does not work because P9 can at most provide an…
It is suggested that gravity waves could, in several cases, be detected by means of already (or shortly to be) available technology, independently of current efforts of detection. The present is a follow-up on a recently suggested detection…
Under the hypothesis that self-reproducing probes have formed a galactic-scale communication network by direct Gravitationally-Lensed (GL) links between neighboring systems, we identify Wolf 359, the third nearest stellar system, as an…
Observations of clustering among the orbits of the most distant trans-Neptunian objects (TNOs) has inspired interest in the possibility of an undiscovered ninth planet lurking in the outskirts of the solar system. Numerical simulations by a…
We detect a cold, terrestrial planet in a binary-star system using gravitational microlensing. The planet has low mass (2 Earth masses) and lies projected at $a_{\perp,ph}$ ~ 0.8 astronomical units (AU) from its host star, similar to the…
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…