14 DAY TRIAL // Understanding the delicately balanced “dance” of forces that make a solar system stick together in an orderly fashion has been a long-term goal in astronomy, but difficult to study. This is mostly because we are inside a solar system, therefore it is difficult for us to become outside observers. But a newly found exoplanet, dubbed WASP-18b, promises to become our next big source of knowledge. The body, which some call a “kamikaze” planet, is currently in a very delicate position. It can either fall into its star and get vaporized, or it can be shredded to tiny pieces by its vast gravitational forces.
Astronomers already know that planets in all star systems are connected to their stars gravitationally and vice-versa. That is to say, Jupiter, for example, orbits our own Sun at an average distance of about 500 million kilometers. While that may seem to be too far away to make a difference, experts say that the action exerted by the gas giant is enough to move the star's center of gravity by 10,000 kilometers. This means that, theoretically, alien observers could notice the shift and theorize that a planet is causing it.
The same can be seen in the case of the Earth/Moon system. The natural satellite pulls all the oceans and waters on the planet upwards when it passes over, something we have come to know as tides, whereas the Earth has exerted such a strong pull on the Moon, that it has essentially forced it to slow down its rotation and always show us the same face. However, in the case of WASP-18b, which is ten times the mass of Jupiter, it orbits only three million kilometers away from its star, which is close by any standards. The entire system is located some 400 light-years away, in the constellation Phoenix, ScienceNow reports.
In a new paper, published in today's issue of the respected scientific journal Nature, experts from the University of St. Andrews in Fife, the UK, describe how the exoplanet revolves around its parent star in less than a day. Because of its close proximity, it pulls out massive bulges from its star's equator, which make it spin faster. But this is also draining angular momentum from the planet itself, which seems doomed that, in less than 500,000 years, it should fall in the star, or be ripped apart into a Saturn-like ring system.
“It's the find of a lifetime. The beauty of this discovery is that we will be able to know [how WASP-18b will meet its end] within 5 to 10 years. I think that it could go either way – which makes it very exciting,” University of Maryland in College Park astronomer Douglas Hamilton, who has not been part of the new research, says. WASP-18b was discovered with twin telescopes, located in the Canary Islands and South Africa.