Beta Pictoris is a 20-million-year-old star, surrounded by a cloud of gas and dust, and at least one planet, discovered by astronomers in 2009. This exoplanet orbits the star once every 18 to 20 Earth years, and was the first world discovered within such a cloud.
Beta Pictoris is located about 63.4 light years from Earth, seen in the constellation of Pictoris. This star has 75 percent more mass than the Sun, and it is 8.7 times as bright as our stellar companion.
Astronomers took another photograph of the star in 2012, as seen in visible light. This new image reveals the inner part of the disk has been warped and altered by gravitation from the planet.
However, the rest of the disk remained largely unchanged during that time. This lack of any apparent change in the shroud suggested the cloud is mostly homogeneous, with little difference between different regions.
The dust cloud was examined by astronomers to a distance of 650 million miles from the star, roughly seven times the distance between the Earth and Sun. The globe orbiting the star created a complex arrangement within the gas, matching predictions.
"Some computer simulations predicted a complicated structure for the inner disk due to the gravitational pull by the giant planet. The new images reveal the inner disk and confirm the predicted structures. This finding validates models that will help us to deduce the presence of other exoplanets in other disks," Daniel Apai of the University of Arizona, Tucson said.
This distinctive warping of gas and dust by the planet could provide a new means for astronomers to discover alien worlds around other stars possessing similar clouds.
The Hubble Space Telescope has imaged around two dozen stars with circumstellar disks, but Beta Pictoris provides a unique viewing opportunity. Not only is the star relatively close to Earth, but the disk is seen edge-on from our planet. Vast quantities of dust in the cloud reflect large amounts of light from the star, making the disk relatively easy to see using the Hubble observatory.
It is possible that much of the dusty material in the disk may have been created by the collision between rocky bodies. This includes an area in the southwestern region of the cloud that may have been formed from the collision of a body the size of Mars.
This new image of Beta Pictoris and the shroud of material surrounding it could provide astronomers with knowledge about how stellar systems form. Actions of gas, dust and rocks surrounding the star could show how other stars, and their companion planets, asteroids, and comets come into existence.
"The Beta Pictoris disk is the prototype for circumstellar debris systems, but it may not be a good archetype," Glenn Schneider of the University of Arizona said.
