Related papers: The Occurrence of Earth-Like Planets Around Other …
Studies of transiting extra-solar planets are of key importance for understanding the nature of planets outside our Solar System, because their densities can be determined, constraining of what the planets are made of. Using the data…
Most known extrasolar planets (exoplanets) have been discovered using the radial velocity$^{\bf 1,2}$ or transit$^{\bf 3}$ methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that…
When an extrasolar planet passes in front of its star (transits), its radius can be measured from the decrease in starlight and its orbital period from the time between transits. Multiple planets transiting the same star reveal more: period…
Exoplanets classified as super-Earths are commonly observed on short period orbits, close to their host stars, but their abundance on wider orbits is poorly constrained. Gravitational microlensing is sensitive to exoplanets on wide orbits.…
Exoplanet occurrence rates facilitate comparisons between observations of planets and theoretical models of planet formation. Despite their deductive power, exoplanet occurrence rates for half the stars in the sky are missing because…
Prior to the 1990s, speculations about the occurrence of planets around other stars were based only on planet formation theory, observations of circumstellar disks, and the knowledge that at least one seemingly ordinary star is the host of…
Prior to the 1990s, speculations about the occurrence of planets around other stars were based only on planet formation theory, observations of circumstellar disks, and the knowledge that at least one seemingly ordinary star had managed to…
The search for extrasolar Earth-like planets is underway. Over 100 extrasolar giant planets are known to orbit nearby sun-like stars, including several in multiple-planet systems. These planetary systems are stepping stones for the search…
The discovery of the first extra-solar planet surrounding a main-sequence star was announced in 1995, based on very precise radial velocity (Doppler) measurements. A total of 34 such planets were known by the end of March 2000, and their…
Binary stars are ubiquitous; the majority of solar-type stars exist in binaries. Exoplanet occurrence rate is suppressed in binaries, but some multiples do still host planets. Binaries cause observational biases in planet parameters, with…
Recent astronomical observations, in particular from the Kepler and TESS missions and their related follow-ups, have revealed an abundance of exoplanets in the size range between Neptune (4 Earth radii) and Earth (1 Earth radii ), as well…
In order to gain a better understanding of planet formation and evolution, it is important to examine the statistics of exoplanets in the Galactic context. By combining information on stellar elemental abundances and kinematics, we…
We present Kepler exoplanet occurrence rates for planets between $0.5-16$ R$_\oplus$ and between $1-400$ days. To measure occurrence, we use a non-parametric method via a kernel density estimator and use bootstrap random sampling for…
We analyze the effect of companion stars on the bulk density of 29 planets orbiting 15 stars in the Kepler field. These stars have at least one stellar companion within 2", and the planets have measured masses and radii, allowing an…
The nearly circular (mean eccentricity <e>~0.06) and coplanar (mean mutual inclination <i>~3 deg) orbits of the Solar System planets motivated Kant and Laplace to put forth the hypothesis that planets are formed in disks, which has…
Observational surveys for extrasolar planets probe the diverse outcomes of planet formation and evolution. These surveys measure the frequency of planets with different masses, sizes, orbital characteristics, and host star properties. Small…
Probing the connection between a star's metallicity and the presence and properties of any associated planets offers an observational link between conditions during the epoch of planet formation and mature planetary systems. We explore this…
The chemical composition of stars hosting small exoplanets (with radii less than four Earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-rich. This implies that small, including Earth-size, planets…
In Lammer et al. 2024, we defined Earth-like Habitats (EH) as rocky planets in the habitable zone of complex life (HZCL) on which Earth-like N$_2$-O$_2$-dominated atmospheres with minor amounts of CO$_2$ can exist and derived a formula for…
Among the hundred or so extrasolar planets discovered to date, 19 are orbiting a component of a double or multiple star system. In this paper, we discuss the properties of these planets and compare them to the characteristics of planets…