New Delhi: Astronomers have announced the discovery of a third planet in the Kepler-47 system, marking the most intriguing of the binary-star systems. The new discovery, made using data from NASA’s Kepler space telescope, was conducted by a team from San Diego State University. The newly identified planet, Kepler-47d, orbits between Neptune and Saturn, two previously known planets in size and composition.
Kepler-47, with its three planets orbiting two of the Sun, is the only known multiplanetary system. Orbital planets are those that revolve around two stars. This unique arrangement is characterized by a „transit pattern” where planets pass in front of their stars, causing a detectable drop in brightness from Earth.
Detection of Kepler-47d was initially challenging due to weak transit signals. However, over time, the middle planet’s orbital plane shifted to a more favorable alignment, significantly improving its transit signal from undetectable at the start of the Kepler mission, to become more pronounced in three of the four years.
Jerome Oros, SDSU astronomer and lead author of the study, shared his initial suspicions of a third planet in 2012, but clarity only came with more data. „We saw a hint of a third planet in 2012, but needed more data to be sure with just one transit,” Oros explained. Find additional traffic hidden in the noise in previous data.”
William Welsh, co-author and SDSU astronomer, expressed surprise at the findings: „We certainly didn’t expect this to be the largest planet in the system. It almost came as a shock.”
The discovery improves understanding of the Kepler-47 system, revealing that its planets are less dense than Saturn, the least dense of any planet in our Solar System. Kepler-47d’s equilibrium temperature is approximately 50 degrees Fahrenheit, which is significantly milder compared to the system’s inner and much hotter planet.
The study, recently published in the Astronomical Journal and supported by NASA and the National Science Foundation, highlights the commonality of systems with close-packed, low-density planets throughout our galaxy.
Kepler-47, with its three planets orbiting two of the Sun, is the only known multiplanetary system. Orbital planets are those that revolve around two stars. This unique arrangement is characterized by a „transit pattern” where planets pass in front of their stars, causing a detectable drop in brightness from Earth.
Detection of Kepler-47d was initially challenging due to weak transit signals. However, over time, the middle planet’s orbital plane shifted to a more favorable alignment, significantly improving its transit signal from undetectable at the start of the Kepler mission, to become more pronounced in three of the four years.
Jerome Oros, SDSU astronomer and lead author of the study, shared his initial suspicions of a third planet in 2012, but clarity only came with more data. „We saw a hint of a third planet in 2012, but needed more data to be sure with just one transit,” Oros explained. Find additional traffic hidden in the noise in previous data.”
William Welsh, co-author and SDSU astronomer, expressed surprise at the findings: „We certainly didn’t expect this to be the largest planet in the system. It almost came as a shock.”
The discovery improves understanding of the Kepler-47 system, revealing that its planets are less dense than Saturn, the least dense of any planet in our Solar System. Kepler-47d’s equilibrium temperature is approximately 50 degrees Fahrenheit, which is significantly milder compared to the system’s inner and much hotter planet.
The study, recently published in the Astronomical Journal and supported by NASA and the National Science Foundation, highlights the commonality of systems with close-packed, low-density planets throughout our galaxy.