Young Exoplanet Offers Clues to How Earth Was Formed
Astronomers have detected water vapor and carbon monoxide in the atmosphere of a planet 130 light years away from Earth. Scientists believe that this will not only help solve mysteries of how it was formed, but also how our own solar system came to be.
The planet, known only as HR8799c, is devoid of methane, a gas that can indicate life, the researchers said. It is home to four giant planets orbiting a relatively young, 30-million-year-old star, with each planet far larger than any world found in Earth's solar system. The observations, made using at the Keck Observatory in Hawaii, were published online in the journal Science.
According to the report, the planets orbiting HR 8799 weigh in at between five to 10 times the mass of Jupiter and are still glowing with the heat of their formation. The study is the most detailed yet of the atmosphere of an "exoplanet".
Dr Bruce Macintosh, from the Lawrence Livermore National Laboratory in California, US, one of the co-authors of the research published in the journal Science, said: "This is the sharpest spectrum ever obtained of an extrasolar planet. This shows the power of directly imaging a planetary system. It is the exquisite resolution afforded by these new observations that has allowed us to really begin to probe planet formation."
Observations suggest the solar system was created in a similar way to our own, with gas giants forming far away from their parent star and smaller, rocky planets closer in. If this model is correct, there could be as-yet undetected Earth-like planets waiting to be found.
"The results suggest the HR 8799 system is like a scaled-up Solar System," said Dr Quinn Kanopacky, one of the astronomers from the University of Toronto in Canada.
"Once the solid cores grew large enough, their gravity quickly attracted surrounding gas to become the massive planets we see today," added Konopacky. "Since that gas had lost some of its oxygen, the planet ends up with less oxygen and less water than if it had formed through a gravitational instability."