Astronomers have found that the first exoplanet that was identified transiting its star could have migrated to a close orbit with its star from its original birthplace further away. The results were published in the journal Nature by the international team of astronomers.
The team from the University of Warwick Analyzed the planet’s atmosphere has identified the chemical fingerprint of a planet that formed much further away from its sun than it currently resides.it confirms the old thinking that the planet moved to its current position after forming, a mere 7 million km from its sun or the equivalent of 1/20th the distance from the Earth to our Sun.
The University of Warwick led the modeling and interpretation of the results which mark the first time that as many as six molecules in the atmosphere of an exoplanet have been measured to determine its composition.Astronomers have used these six molecules to pinpoint the location at which these hot, giant planets form. With new technology and more powerful telescopes coming online soon, their technique could also be used to study the chemistry of exoplanets that could potentially host life.
Astronomers detected hydrogen cyanide, methane, ammonia, acetylene, carbon monoxide and low amounts of water vapor in the atmosphere of HD 209458b. The unexpected abundance of carbon-based molecules suggests that there are approximately as many carbon atoms as oxygen atoms in the atmosphere, double the carbon expected. This suggests that the planet has preferentially accreted gas rich in carbon during formation, which is only possible if it orbited much further out from its star when it originally formed, most likely at a similar distance to Jupiter or Saturn in our own solar system.