Jupiter – friend or foe? II: the Centaurs

  title={Jupiter – friend or foe? II: the Centaurs},
  author={Jonti Horner and Barrie W. Jones},
  journal={International Journal of Astrobiology},
  pages={75 - 80}
Abstract It has long been assumed that the planet Jupiter acts as a giant shield, significantly lowering the impact rate of minor bodies upon the Earth, and thus enabling the development and evolution of life in a collisional environment which is not overly hostile. In other words, it is thought that, thanks to Jupiter, mass extinctions have been sufficiently infrequent that the biosphere has been able to diversify and prosper. However, in the past, little work has been carried out to examine… Expand
Jupiter – friend or foe? III: the Oort cloud comets
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Jupiter: Cosmic Jekyll and Hyde.
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The influence of Jupiter, Mars and Venus on Earth’sorbital evolution
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It has long been thought that the presence of a giant planet is a pre-requisite for the development of life on potentially habitable planets. Without Jupiter, it was argued, the Earth would have beenExpand
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In coming years, the first truly Earth-like planets will be discovered orbiting other stars, and the search for signs of life on these worlds will begin. However, such observations will be hugelyExpand
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  • J. Horner, B. Jones
  • Computer Science, Physics
  • International Journal of Astrobiology
  • 2010
This work reviews the various planetary, dynamical and stellar influences that could influence the habitability of exoEarths and decides where to focus the first detailed search for life beyond the authors' Solar System. Expand
Prospecting for exo-Earths in multiple planet systems with a gas giant
In this work, we hunt for the best places to find exo-Earths in the currently known exoplanet population. While it is still unclear whether Jupiter had a beneficial or detrimental effect on theExpand


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Abstract The asteroids are a major source of potential impactors on the Earth today. It has long been assumed that the giant planet Jupiter acts as a shield, significantly lowering the impact rate onExpand
On the origin of the unusual orbit of Comet 2P/Encke
Abstract The orbit of Comet 2P/Encke is difficult to understand because it is decoupled from Jupiter—its aphelion distance is only 4.1 AU . We present a series of orbital integrations designed toExpand
Possible consequences of absence of “jupiters” in planetary systems
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  • Physics, Medicine
  • Astrophysics and space science
  • 1994
The formation of the gas giant planets Jupiter and Saturn probably required the growth of massive ∼ 15 Earth-mass cores on a time scale shorter than the ∼ 107 time scale for removal of nebular gas, but the probability of similar gas giants occurring in other planetary systems is unclear. Expand
From the Kuiper Belt to Jupiter-Family Comets: The Spatial Distribution of Ecliptic Comets☆
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This model not only naturally explains the Late Heavy Bombardment, but also reproduces the observational constraints of the outer Solar System. Expand
The populations of comet-like bodies in the Solar system
A new classification scheme is introduced for comet-like bodies in the Solar system. It covers the traditional comets as well as the Centaurs and Edgeworth–Kuiper belt objects. At low inclinations,Expand
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Large-scale simulations of the Centaur population are carried out. The evolution of 23 328 particles based on the orbits of 32 well-known Centaurs is followed for up to 3 Myr in the forward andExpand
Persistent hazardous environments around stars older than the Sun
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  • International Journal of Astrobiology
  • 2006
Collisions amongst comets create belts of orbiting debris and, by using submillimetre wavelength observations, these collision zones can be imaged around nearby stars. An image of the closest SolarExpand
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Detailed orbit integrations of clones of five Centaurs ‐ namely, 1996 AR20, 2060 Chiron, 1995 SN55, 2000 FZ53 and 2002 FY36 ‐ for durations of ∼3 Myr are presented. One of our Centaur sample startsExpand
Perihelion evolution of observed new comets implies the dominance of the galactic tide in making Oort cloud comets discernable
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