The Hubble Space Telescope has captured an amazingly detailed image of a dusty disk surrounding a star known as Beta Pictoris.
The 20-million-year-old star is the only directly imaged debris disk which encircles a giant planet, and this latest Hubble image has revealed some of its secrets to scientists. Its orbital period of 18-22 years is relatively short, which allows astronomers to observe a large range of motion in a short period of time. By studying the star scientists are able to analyze the distorting effects of the giant planet on the debris disk that surrounds it, writes Catherine Griffin of Science World Report.
Hubble images validate computer models
“Some computer simulations predicted a complicated structure for the inner disk due to the gravitational pull by the short-period giant plant,” said Daniel Apai, a member of the research team. “The new images reveal the inner disk and confirm the predicted structures. This finding validates models, which will help us to deduce the presence of other exoplanets in other disks.”
By comparing the new Hubble image to previous images, astronomers observed that the distribution of the dust has changed very little over the intervening 15 years, despite its range of movement. Beta Pictoris is located around 63 light-years from Earth, which means it is closer to Earth than most known disc systems, and is easily observable because it is tilted edge-on to the Earth.
The formation has been the subject of sustained study by both Hubble and ground-based telescopes since its discovery in 1984, and scientists say that it is the best example of a young planetary system.
A specific case?
However the latest findings do not mean that the Beta Pictoris model should be applied to all circumstellar debris disks, whose structure and amount of dust varies greatly. “The Beta Pictoris disc is the prototype for circumstellar debris systems, but it may not be a good archetype,” said study co-author Glenn Schneider of the University of Arizona.
It has been noted that the Beta Pictoris disk contains a higher than average amount of dust, which may be due to collisions between celestial bodies which scientists have not yet been able to see. However astronomers have speculated that one particularly bright area of dust and gas could have resulted from the pulverization of a space object the size of Mars.
Although the study represents a breakthrough in our understanding of circumstellar debris disks, it does not provide a definitive model for every example of them.
