scholarly journals A Step Toward Eta-sub-Earth

2012 ◽  
Vol 8 (S293) ◽  
pp. 84-87
Author(s):  
Wesley A. Traub
Keyword(s):  
Type Star ◽  
Terrestrial Planets ◽  
Habitable Zone ◽  
Reaction Wheel ◽  
Expected Number ◽  
Initial Examination ◽  
True Value ◽  
Kepler Mission ◽  
Solar Type ◽  
Solar Type Star

AbstractThe Kepler mission observed exoplanet transits for 4 full years (greater than its expected lifetime of 3.5 years) until it became inoperable for its original purpose, as a result of a reaction wheel failure. Kepler was spectacularly successful in its goal of observing exoplanet transits of host star disks for the purpose of measuring the statistics of such transits in its target star sample. The Kepler data, when fully analyzed, will determine the statistics of planets in the underlying population, and in particular the expected number of terrestrial planets in habitable zone orbits per solar-type star, the quantity known as eta-sub-Earth. This report is an initial examination of Kepler's third catalog (Feb. 2012) of planets and candidate planets. I find that the apparent projected value of eta-sub-Earth is several times smaller than I had found from the second catalog, but that the data are now approaching the point where intrinsic biases can be uncovered. When all bias factors are eventually found, it is likely that the true value of eta-sub-Earth will be substantially greater than its current apparent value.

scholarly journals Case studies of habitable Trojan planets in the system of HD 23079

2011 ◽  
Vol 10 (4) ◽  
pp. 325-334 ◽  
Author(s):  
J. Eberle ◽  
M. Cuntz ◽  
B. Quarles ◽  
Z.E. Musielak
Keyword(s):  
Case Studies ◽  
Giant Planet ◽  
Outer Edge ◽  
Type Star ◽  
Initial Condition ◽  
Habitable Zone ◽  
Orbital Parameters ◽  
The Earth ◽  
Solar Type ◽  
Solar Type Star

AbstractWe investigate the possibility of habitable Trojan planets in the HD 23079 star–planet system. This system consists of a solar-type star and a Jupiter-type planet, which orbits the star near the outer edge of the stellar habitable zone in an orbit of low eccentricity. We find that in agreement with previous studies Earth-mass habitable Trojan planets are possible in this system, although the success of staying within the zone of habitability is significantly affected by the orbital parameters of the giant planet and by the initial condition of the theoretical Earth-mass planet. In one of our simulations, the Earth-mass planet is captured by the giant planet and thus becomes a habitable moon.

scholarly journals COMMISSION 53: EXTRASOLAR PLANETS

2008 ◽  
Vol 4 (T27A) ◽  
pp. 181-182
Author(s):  
Michel Mayor ◽  
Alan P. Boss ◽  
Paul R. Butler ◽  
William B. Hubbard ◽  
Philip A. Ianna ◽  
...  
Keyword(s):  
Working Group ◽  
Extrasolar Planets ◽  
Theoretical Work ◽  
Vice President ◽  
The Other ◽  
Type Star ◽  
Extrasolar Planet ◽  
General Assembly ◽  
Solar Type ◽  
Solar Type Star

Commission 53 on Extrasolar Planets was created at the 2006 Prague General Assembly of the IAU, in recognition of the outburst of astronomical progress in the field of extrasolar planet discovery, characterization, and theoretical work that has occurred since the discovery of the pulsar planets in 1992 and the discovery of the first planet in orbit around a solar-type star in 1995. Commission 53 is the logical successor to the IAU Working Group on Extrasolar Planets WG-ESP, which ended its six years of existence in August 2006. The founding president of Commission 53 is Michael Mayor, in honor of his seminal contributions to this new field of astronomy. The vice-president is Alan Boss, the former chair of the WG-ESP, and the members of the Commission 53 Organizing Committee are the other former members of the WG-ESP.

A Non‐LTE Line‐Blanketed Model of a Solar‐Type Star

2005 ◽  
Vol 618 (2) ◽  
pp. 926-938 ◽  
Author(s):  
C. I. Short ◽  
P. H. Hauschildt
Keyword(s):  
Type Star ◽  
Solar Type ◽  
Solar Type Star

scholarly journals Physical properties of terrestrial planets and water delivery in the habitable zone using N-body simulations with fragmentation

2019 ◽  
Vol 632 ◽  
pp. A14 ◽  
Author(s):  
A. Dugaro ◽  
G. C. de Elía ◽  
L. A. Darriba
Keyword(s):  
Terrestrial Planets ◽  
Habitable Zone ◽  
Water Delivery ◽  
Class A ◽  
Class B ◽  
Solar Type ◽  
Formation And Evolution ◽  
Final Fraction ◽  
The Masses ◽  
Water Contents

Aims. The goal of this research is to study how the fragmentation of planetary embryos can affect the physical and dynamical properties of terrestrial planets around solar-type stars. Our study focuses on the formation and evolution of planets and water delivery in the habitable zone (HZ). We distinguish class A and class B HZ planets, which have an accretion seed initially located inside and beyond the snow line, respectively. Methods. We developed an N-body integrator that incorporates fragmentation and hit-and-run collisions, which is called D3 N-body code. From this, we performed 46 numerical simulations of planetary accretion in systems that host two gaseous giants similar to Jupiter and Saturn. We compared two sets of 23 N-body simulations, one of which includes a realistic collisional treatment and the other one models all impacts as perfect mergers. Results. The final masses of the HZ planets formed in runs with fragmentation are about 15–20% lower than those obtained without fragmentation. As for the class A HZ planets, those formed in simulations without fragmentation experience very significant increases in mass with respect to their initial values, while the growth of those produced in runs with fragmentation is less relevant. We remark that the fragments play a secondary role in the masses of the class A HZ planets, providing less than 30% of their final values. In runs without fragmentation, the final fraction of water of the class A HZ planets keeps the initial value since they do not accrete water-rich embryos. In runs with fragmentation, the final fraction of water of such planets strongly depends on the model used to distribute the water after each collision. The class B HZ planets do not show significant differences concerning their final water contents in runs with and without fragmentation. From this, we find that the collisional fragmentation is not a barrier to the survival of water worlds in the HZ.

scholarly journals Fifteen years in the high-energy life of the solar-type star HD 81809

2017 ◽  
Vol 605 ◽  
pp. A19 ◽  
Author(s):  
S. Orlando ◽  
F. Favata ◽  
G. Micela ◽  
S. Sciortino ◽  
A. Maggio ◽  
...  
Keyword(s):  
High Energy ◽  
Type Star ◽  
Solar Type ◽  
Solar Type Star

scholarly journals MAGNETIC CYCLES IN A CONVECTIVE DYNAMO SIMULATION OF A YOUNG SOLAR-TYPE STAR

2011 ◽  
Vol 731 (1) ◽  
pp. 69 ◽  
Author(s):  
Benjamin P. Brown ◽  
Mark S. Miesch ◽  
Matthew K. Browning ◽  
Allan Sacha Brun ◽  
Juri Toomre
Keyword(s):  
Type Star ◽  
Solar Type ◽  
Magnetic Cycles ◽  
Solar Type Star

scholarly journals Photospheric and chromospheric activity on the young solar-type star HD 171488 (V889 Herculis)

2010 ◽  
Vol 518 ◽  
pp. A48 ◽  
Author(s):  
A. Frasca ◽  
K. Biazzo ◽  
Zs. Kővári ◽  
E. Marilli ◽  
Ö. Çakırlı
Keyword(s):  
Type Star ◽  
Chromospheric Activity ◽  
Solar Type ◽  
Solar Type Star
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