Andre W. answered 10/05/13
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Assuming this planet orbits our Sun, we can use Kepler's 3rd law to find its distance from the Sun: If T is the planet's period, its average distance from the Sun r is given by
T²=r³,
where T is in earth years and r in astronomical units (AU). With T=423 days = 1.16 years we get
r = (1.16²)1/3=1.10 AU,
which puts this planet outside earth's orbit (1.0 AU by definition), but inside Mars's orbit (1.5 AU). That means it is a terrestrial planet like Earth and Mars, so it is small, rocky and has a metallic core, with few or no moons.
For it to have an average surface temperature higher than earth's (40°C>15°C), it must have an atmosphere which is denser than the earth's atmosphere and/or contains more greenhouse gases like carbon dioxide or methane. These gases cause the greenhouse effect, which is responsible for an increase in surface temperature.
The planet would still be in the habitable zone, where surface water could be liquid year-round, depending on the tilt of its axis, its rotational period, and the eccentricity of its orbit.