Related papers: Detecting Planet 9 via Hawking radiation
This paper presents strong observational evidence of numerous previously unobserved anomalous circular spots, of significantly raised temperature, in the CMB sky. The spots have angular radii between 0.03 and 0.04 radians (i.e. angular…
Hawking radiation would make microscopic black holes evaporate rapidly, which excludes them from many astrophysical considerations. However, it has been argued that the quantum nature of space would alter this behaviour: the temperature of…
We report discovery of a bright, nearby ($G = 13.8;\,\,d = 480\,\rm pc$) Sun-like star orbiting a dark object. We identified the system as a black hole candidate via its astrometric orbital solution from the Gaia mission. Radial velocities…
A class of extrasolar giant planets - the so-called `hot Jupiters' - orbit within 0.05 AU of their primary stars. These planets should be hot and so emit detectable infrared radiation. The planet HD 209458b is an ideal candidate for the…
Searches for planets via gravitational lensing have focused on cases in which the projected separation, a, between planet and star is comparable to the Einstein radius, R_E. This paper considers smaller orbital separations and demonstrates…
Cosmological measurements indicate that a large component of non-visible gravitating matter is present in the universe. A common hypothesis for its origin is a weakly interacting, massive particle. Annihilations or decays of such particles…
A new class of Kuiper belt objects that lie beyond Neptune with semimajor axes greater than 250 astronomical units show orbital anomalies that have been interpreted as evidence for an undiscovered ninth planet. We show that a modified…
Primordial black holes (PBHs) in the asteroid-mass range, with typical masses $10^{17}\,{\rm g}\lesssim M \lesssim 10^{23}\,{\rm g}$, have drawn significant recent attention as a viable dark matter candidate. The peak frequencies of photons…
The source X-9 was discovered with the {\it Einstein Observatory} in the field of M81, and is located in the dwarf galaxy Holmberg IX. X-9 has a 0.2-4.0 keV luminosity of $\sim 5.5\times 10^{39}$ ergs~s$^{-1}$, if it is at the same distance…
The dust tails of comets similar to Hale-Bopp can scatter as much optical light as does the Earth. Space-based observatories such as the Terrestrial Planet Finder or Darwin that will detect extra-solar terrestrial planets also will be able…
Over the last few years, several close orbiting ($\sim 0.05$ AU) large mass planets ($M \sim M_{Jupiter}$) of nearby stars have been discovered. Their existence has been inferred from tiny doppler shifts in the light from the star. We…
We have searched for and estimated the possible gravitational influence of dark matter in the Solar system based on the EPM2011 planetary ephemerides using about 677 thousand positional observations of planets and spacecraft. Most of the…
Previously, planets have been detected only in the Milky Way galaxy. Here, we show that quasar microlensing provides a means to probe extragalactic planets in the lens galaxy, by studying the microlensing properties of emission close to the…
If primordial black holes (PBH) saturate the present upper limit on the dark matter density in our Solar system and if their radiation spectrum is discrete, the sensitivity of modern detectors is close to that necessary for detecting this…
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…
Radio wavelength astrometry of stars and other objects has a long and productive history. The use of that technique to determine whether stars have planets around them would cover a nearly unique part of the parameter space for detection of…
Hawking radiation, despite its presence in theoretical physics for over thirty years, remains elusive and undetected. It also suffers, in its original context of gravitational black holes, from conceptual difficulties. Of particular note is…
Stars are transparent to the passage of primordial black holes (PBHs) and serve as seismic detectors for such objects. The gravitational field of a PBH squeezes a star and causes it to ring acoustically. We calculate the seismic signature…
High-contrast near-infrared imaging of the nearby star HR 8799 has shown three giant planets. Such images were possible due to the wide orbits (> 25 AU) and youth (< 100 Myr) of the imaged planets, which are still hot and bright as they…
Many black hole (BH) candidates exist, ranging from supermassive ($\sim10^{6}$--$10^{10}$ M$_{\odot}$) to stellar masses ($\sim 1$--$100$ M$_{\odot}$), all of them identified by indirect processes. Although there are no known candidate BHs…