A Hawaiian telescope just discovered a debris disk around a star — a star that’s so young, it may have been formed after humans split from chimps. Researchers have been working on an instrument at the Subaru Telescope on Maunakea, Hawaii called the Subaru Coronagraphic Extreme Adaptive Optic (SCExAO), which is specifically designed for imaging exoplanets. The team will publish its findings about SCExAO’s first discovery from last October in a new issue of Astrophysical Journal Letters.
“We’re trying not to only image planets or planet-forming disks, but at some point, we want to be able to image and study mature planets, planets with ages comparable to the solar system,” Thayne Currie, who authored the first science result paper, tells Inverse. “…It’s exciting not just for astronomy but for humanity in general.”
SCExAO revealed images of a debris disk around HD 36546, a star that is twice the size of the sun in the constellation Taurus. The debris disk is very far from its star — in fact, it’s located twice the distance from HD 36546 that the Kuiper Belt is from the sun. The debris likely came about because of icy planet formation and can help scientists study the early stages of this process and better understand our own solar system.
“That’s a perfect environment for planets to form out of,” Nemanja Jovanovic of the SCExAO team tells Inverse. “That’s a nursery.”
Researchers believe HD 36546 is part of an association of stars 3 million to 10 million years old. If this is true, the debris disk found may be the youngest debris every imaged. To put this into perspective, our sun is 4.5 billion years old, and the oldest star of this association formed when humans split from chimps 10 million years ago.
“The really interesting thing about the discovery is the age of the system,” Currie says. “Most debris disks that we’re able to image are several tens of millions of years old. That probes the stage of the building blocks of planet formation.”
SCExAO can compensate for how the atmosphere blurs images of stars. As a result, its images are much sharper, and now we can more clearly see exoplanets like those in our solar system.
Right now though, we still can’t see planets that are potentially habitable like Earth. This is because they are fainter, smaller, and closer to the host star. Currie believes we won’t able to see Earth-like planets for another eight to ten years. On the other hand, SCExAO can see planets more similar to Jupiter — larger and farther away from the star.
“They’re much bigger balls of gas, which makes them easier to see than an Earthlike planet,” Jovanovic says. “An Earthlike planet or terrestrial planet is much smaller. It’s a challenge to see those types of planets.”
In the meantime, the team will work to characterize known and new planetary systems. SCExAO has already imaged all four planets in the HR 8799 system, which hosts the first planets ever directly imaged.
In the coming year, the SCExAO will continue improving the instrument so it can image planets that are orbiting closer to their host stars and eventually discover planets 10 to 100 times fainter.
“This instrument is a bit unique in a way where we’re constantly improving and evolving it,” SCExAO project lead Olivier Guyon tells Inverse. “…The very big picture potential of this instrument is to lead us to habitable planet imaging in next generation instruments.”
