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Sigma Draconis (Alsafi)

Sigma Draconis is a K0 V orange star 18 light-years from earth in the constellation Draco.  It is both smaller and cooler than Sol, and slightly metal-poor.  It is one of the least variable stars measured to date, and has an unusually eccentric galactic orbit (0.3 eccentricity, compared to Sol's 0.06).

It has a large solar system of thirteen planets, including one earth-like world (IV - Asherah) and another which may be a suitable prospect for terraforming (VI - Wigaunt).  The planets were named by the astronomers who discovered their existence using the initial survey probe results.

Kaleda, Sinmore, and Benisa (Sigma Draconis I-III)

The inner three worlds of the Sigma Draconis system are all small, airless, rocky worlds that are tidally locked to the star.  Kaleda is a little smaller than Luna, and much less massive.  Sinmore is about half the size of Earth and 12% of it's mass.  It is named after the Queen of Muspelheim (Norse realm of Fire) and the wife of the Norse god Surt in Wagner's Götterdämmerung.  Benisa is a bit larger than Kaleda and four times as massive.

Asherah (Sigma Draconis IV)


The only truly habitable planet in the system.  Asherah is a water world, with a chilly and damp climate almost year-round at most latitudes, due to the relative dimness of the host star and the slight, eight degree axial tilt.  Temperature ranges from an average of 27.8 degrees fahrenheit at night to 51.5 degrees in the day (-2.3 to 10.8 deg C).  The weather tends toward dense morning/evening fog and bleak, overcast days at all but the equatorial and polar latitudes.  The day is just short of 20 standard hours in length.

The surface of the planet remains largely unexplored.  It consists of a handful of smallish continental and subcontinental landmasses, and a large number of smaller islands.

Asherah has two moons, Threnody and Terpischore, both of which appear larger in the sky than Luna (Threnody, the larger and closer of the two, covers 1.38 angular degrees, about 2.75 times as large as Luna).  Thanks to its moons, Asherah has stronger and more complex tides than earth, and total eclipses are fairly commmon.

Native Ecology

There is no known sapient life on the planet, but there are a number of interesting subsapient life forms.

One peculiarity of Asherah's ecosystem is that the plant kingdom has evolved many of the characteristics and fills many of the niches usually held by animals on other worlds, including mobility (many of the floral organisms are non-sessile for at least part of their lifespan), and even limited intelligence.  The Kukta, for example, is a perennial flowering organism roughly analogous to a dog or cat, which is easily domesticated and makes a loyal and well-behaved pet.  Kukta are low-maintenance, requiring only sufficient water, sunlight, and a fairly wide range of soil conditions, and house-breaking is never a problem.  They also smell nice and are a riot of color when they bloom.

Visitors would be well-advised to familiarize themselves with the more dangerous known predatory plant species before arrival.

Arien (Sigma Draconis V)

This planet seems to be the core of a failed Jovian world, and the innermost of three planets that are unusually inclined to the plane of the rest of the system.  Astronomers suggest that some ancient catastrophe stripped Arien of much of its atmosphere and placed Wigaunt into a more eccentric orbit.

Wigaunt (Sigma Draconis VI)

Aside from Asherah, Wigaunt is probably the best prospect for colonization in the Sigma Draconis system.  It is somewhat more hospitable than Mars, having a surface gravity of nearly half a standard g, and a correspondingly thicker atmosphere (thin, but breathable).

The planet is, however, rather cold.  The "continental" plateaus and poles are entirely frozen over, resulting in a 43% ice cover.  The "ocean floors" are considerably warmer, due to geological activity, enough so to support small plant life.

Skall (Sigma Draconis VII)

An ice world, too cold to be very hospitable.  It has a thick atmosphere that refracts light strongly.  Seen from space, the night side of the planet is encircled by a brilliant orange sunset.

Barrilock (Sigma Draconis VIII)

One of three Jovian worlds in this system.

Elyon (Sigma Draconis IX)

A Jovian world, the largest in the system.  The name means "Most High".  An unusual thermal inversion structure in Elyon's upper atmosphere traps two layers of tiny particles that serve as a sort of planetary fibre-optic network, channelling some of the sunlight from the day side around to the night, making the dark clouds radiate a dull red light.

Scrokallan (Sigma Draconis X)

The third of Sigma Draconis's three Jovian worlds.

Enmassara (Sigma Draconis XI)

A golden subjovian planet, just under three earth masses, but several times as large.

Tinati (Sigma Draconis XII)

An airless, rocky planet.  Tinati is about 80% of the size of the earth, but has only a third of the surface gravity.

Rinn (Sigma Draconis XIII)

A large but light body far out on the outskirts of the system.  It takes over 330 earth years to complete a single orbit.  Like Arien and Tinati, Rinn is strongly inclined to the plane of the other planets in the system.