Hubble Space Telescope Uncovers Startling Diversity in Debris-Strewn Systems

Using the Hubble Space Telescope, astronomers have uncovered a startling diversity in debris systems that coincide with the formation of exoplanets. The findings reveal that there may be some kind of interdependent between a planet and the accompanying debris system.

Using Hubble, scientists have completed the large and most sensitive visible-light imaging survey of dusty debris disks around other stars. These disks, likely created by collisions between leftover objects from planet formation, were seen around stars as young as 10 million years old and as mature as more than 1 billion years old.

"It's like looking back in time to see the kinds of destructive events that once routinely happened in our solar system after the planets formed," said Glenn Schneider, the survey leader, in a news release.

Although researchers once believed that these disks followed simple pancake-like structures, they instead found an unexpected diversity and complexity and varying distribution of dust among these debris system. This suggested that these disks are gravitationally affected by unseen planets orbiting the star.

"We find that the systems are not simply flat with uniform surfaces," said Schneider. "These are actually pretty complicated three-dimensional debris systems, often with embedded smaller structures. Some of the substructures could be signposts of unseen planets."

In one ring-like system in particular, around a star called HD 181327, scientists witness an ejection of a huge spray of debris into the outer part of the system from the recent collision of two bodies.

"This spray of material is fairly distant from its host star-roughly twice the distance that Pluto is from the Sun," said Christopher Stark of NASA's Goddard Space Flight Center. "Catastrophically destroying an object that massive at such a large distance is difficult to explain, and it should be very rare. If we are in fact seeing the recent aftermath of a massive collision, the unseen planetary system may be quite chaotic."

The findings reveal a bit more about the diversity of these systems. More specifically, it shows the necessity of understanding the internal and external influences on these systems, such as stellar winds and interactions with clouds of interstellar material.

The findings are published in The Astronomical Journal.