Stellar Data
|
|
Type of Star: Spectral Class: Distance: Luminosity: Mass: Surface Temperature: Main Sequence Lifetime: |
Yellow Dwarf G8V 11,9 Lightyears 0,45 L 0,8 Solar Masses 5.500 K 12 Billion Years |
The Environment of Tau Ceti
|
Habitable Zone: Zone of Stable Planetary Orbits: Known Companions: |
0,6 - 0,9 AU Unlimited None |
Comparison to Solar System
Tau Ceti |
Sun
|
|
As soon as the next century, humans might explore Tau Ceti. |
In all the great oceans of emptiness, stars of type G are the best candidates to look for life - these are stars like our own sun. They are of moderate, but comfortable brightness and remain stable for about 10 billion years - sufficient time for complex life forms to evolve. Tau Ceti is such a G-type, sunlike star, devoid of stellar companions and close enough for detailed studies. |
|
Though Tau Ceti has about half the sun's luminosity, its habitable zone still comprises about one third AU - this is wide enough that a terran planet may have formed there. But we know from other stars that giant gas planets are common, and they are often very close to their parent star. So if Tau Ceti happens to have a system of planets, a gas giant may orbit within the habitable zone, leaving no space for an additional terrestrial planet. But this giant planet may have moons, possibly of Earth's size, where life may get a start. |
|
Climate on such a large moon of Tau Ceti b would not be substantially different from our own. Depending on the parent planet's orbital radius, this world might see the whole range of conditions from the greenhouse of the Mesozoic to the great ice ages of the Pleistocene. Advanced forms of life, even sentient beings, are not excluded. |
|
En julio del 2004, un grupo de astrónomos ingleses encabezados por el Dr. Jane Greaves anunciaron el descubrimiento de un frio disco de polvo alrededor de la estrella. Según sus interpretaciones, el disco se ha originado debido a las colisiones entre grandes cometas y asteroides, los cuales se rompen en trozos más pequeños. Tau Ceti podría contener diez veces más material en forma de asteroides y cometas que nuestro Sistema Solar, lo cual haría que los impactos con planetas alcanzasen tasas muy elevadas. El medio ambiente de Tau Ceti podría ser más hostil para la vida de lo que habíamos imaginado. ¿Es acaso un planeta estable y tranquilo como la Tierra un extraño fenómeno tal y como Peter Ward y Donald Brownlee exponen?. |
|
Heidmann, J. (1994): Bioastronomie WILLIAMS D., KASTING J. & WADE R., 1997: Habitable moons around extrasolar giant planets. Nature, 385, 234 |
