Almost 400 extrasolar planets have been found to date (see Physics Today, May 2009, page 46), but a new planet reported by Coel Hellier (Keele University) and colleagues stands out. Like many exoplanets, theirs, dubbed WASP-18b, is massive (10 times the mass of Jupiter) and has a small orbital radius (only 1/50th of Earth's). But its orbital period of only 0.94 day is the shortest for any "hot Jupiter" yet observed. Moreover, its large mass and small orbit are predicted to cause the strongest tidal interactions of any known star–planet system. According to current theory, the tidal bulge that the planet raises on its host star exerts a torque that will drain angular momentum from the planet and cause it to spiral inward. (For more on tidal interactions, see Physics Today, August 2009, page 11.) If the star's tidal dissipation rate is comparable to what's been measured for binary stars and for the gas giants in our own solar system, the infall will be quick: WASP-18b has less than a million years left in a lifetime, estimated from the age of its host star, of about a billion years. Over the next decade, WASP-18b's death spiral should produce a measurable shift in the planet's observed transit time. The absence of tidal decay—a notable possibility, given the rarity of finding a planet so close to the end of its life—would constitute direct evidence for a different class of tidal interactions in the host star and provide new constraints on models of stellar interiors. (C. Hellier et al., Nature 460, 1098, 2009.)—Richard J. Fitzgerald
A new exoplanet to test tide theories
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New calculations shows that WASP-18b probably not will be stable in its present orbit, but will be thrown away with from the star, with a velocity 3 times higher than the velocity astronomers today believe it “should” approach the star.
This certainly will be a big shock, and something we should be able to confirm within 1 to 2 years.
The idea that also planets are affected of the same accelerating force that space probes (by fly by) support this new theory and make it also possible to understand the cause of the 4 following mysteries:
1.)Why gas-planets can be found very closed to starts ( with their atmosphere intact)
2.)Why huge planets can be found more as 15 billion km. from their mother stars.
3.)How Jupiter’s was created (longer away from the Sun) and what brought it closer to the Sun.
4.)How water came to earth.
Introduction
http://www.science27.com/english/the_pioneer_anomaly.html
Updates:
http://www.science27.com/english/Culcu3.htm
UPDATE
The conclusion in my previous post was wrong.
It’s not enough only to consider the possible force that can be pass by, - based on the angel velocity as a result of a astronomic bodies rotation (centrifugal force) affecting the planet (WASP-18b).
It’s also necessary calculating the possible energy requirement and compare that to the (rotation) energy available due to the stars rotation..
This shows that even though if enough energy fast “could” be transmitted to Wasp-18b, it’s simply not available.
Wasp-18b will therefore approach the star, and will not only be affected by the tidal effect (expected 2.8 s. per year) but will probably also be effected by too weak rotation energy (+ 2 s per year) Total 4.8 s. per year.
However Wasp-18b should have been dismissed for several hundred million years ago. How could it “hide it self” from the tidal force so long time?
The answer seems to be “written in the stars”.
By comparing with other solar systems we can easy understand the logic. (The site is now updated and much better now) >
http://www.science27.com/english/SolarSystems.htm
Sorry for the confusion…