They eliminated those with orbital radii less than one tenth that of Earth's, because at that distance moon systems might not remain in
stable orbits around their planets on billion - year timescales.
Orbity.io is a tricky and very addictive massively multiplayer browser based rocket game in which players attempt to maintain
stable orbits around the planet Earth for as long as possible or take off and explore space.
Not exact matches
For example, William Paley, already in 1802, in his treatise Natural Theology, pointed out that if the law of gravity had not been a so «called «inverse square law» then the earth and the other
planets would not be able to remain in
stable orbits around the sun.
Now, Hippke and Heller show that a combination of the stars» gravity and radiation pressure from their photons can bring the craft into a
stable orbit around one of the stars, then
around the tantalising
planet (Astrophysical Journal Letters, doi.org/bx8t).
He pointed out that there are many close -
orbiting planets around middle - aged stars that are in
stable orbits, but his team doesn't know how quickly this young
planet is going to lose its mass and «whether it will lose too much to survive.»
An Earth - type
planet could have liquid water in a
stable orbit centered
around 0.036 AU from Star B — well within the orbital distance of Mercury in the Solar System.
If so, then conditions would be more favorable for the existence of
stable orbit for an Earth - like
planet (with liquid water) centered
around 1.5 AU from
around Iota Persei —
around the orbital distance of Mars in the Solar System.
An Earth - type
planet could have liquid water in a
stable orbit centered
around 1.18 AU from Star A — between the orbital distances of Earth and Mars in the Solar System.
For an Earth - type
planet around HD 189733 A to have liquid water at its surface, it would need a
stable orbit centered
around 0.5 AU — between the orbital distances of Mercury and Venus in the Solar System (with an orbital period
around 150 days assuming a stellar mass
around 82 percent of Sol's.
Test simulations of the
orbits of the three
planets around 61 Virginis suggest that the planetary system's orbital configuration is dynamically
stable because of low orbital eccentricities for at least 365 million years.
If so, then conditions would be more favorable for the existence of
stable orbit for an Earth - like
planet (with liquid water) centered
around 1.15 AU from
around 15 Sge — between the orbital distances of Earth and Mars in the Solar System.
Assuming that the spectroscopic companion B does not preclude a
stable inner planetary
orbit, the distance from Star A where an Earth - type
planet would be «comfortable» with liquid water is centered
around only 0.457 AU — between the orbital distances of Mercury and Venus in the Solar System.
If so, then conditions would be more favorable for the existence of
stable orbit for an Earth - like
planet (with liquid water) centered
around 1.12 AU from
around 37 Gem — between the orbital distances of Earth and Mars in the Solar System.
An Earth - type
planet could have liquid water in a
stable orbit centered
around 3.5 AU (within a predicted habitable zone ranging between 2.3 and 4.8 AUs) from Star A — between the orbital distances of the Main Asteroid Belt and Jupiter in the Solar System (NASA Stars and Exoplanet Database).
Also nominated for Best Game Audio were Stack & Crack, a 3D puzzle game by Jambav from India;
Orbit — Playing With Gravity, a game that has players launching
planets and attempting to get them into
stable orbits around black holes, by HIGHKEY Games from the United States; and Rumble League, a real - time, action packed strategy game by Lorraine Studio of the United States.