Planet with four suns discovered

If you are living in the newly discovered PH1 (Planet Hunters 1) you are in for a unique phenomenon each "morning" and each "evening". That is four suns rising in the "mornings" and setting in the "evenings". This is what two amateur astronomers found and also stunned the scientific community recently.

The distant body, located less than 5,000 light years from earth, orbits one pair of stars and is circled by a second pair, a type of solar system previously unknown to scientists.

Six circumbinary planets - planets that orbit two suns - have been documented but none of those is orbited by other stars.

The planet was discovered by 'armchair astronomers' Kian Jek, from San Francisco, California, and Robert Gagliano, from Cottonwood, Arizona and is named PH1, after the website used to find it; Planethunters.org.

Planet Hunters is a project run by Yale University which enlists the public to look for signs of new planets. Using data collected by NASA's Kepler space telescope, visitors identify dips in the output of stars caused by their light being blocked by 'transits' of orbiting stars.

By doing so scientists hope to find evidence of new worlds, particularly of Earth-like planets orbiting stars similar to our Sun.

Debra Fischer, a professor of astronomy at Yale, and one of the founders of the Planet Hunters project, said that PH1 "might have been entirely missed if not for the sharp eyes of the public".

Jek and Gagliano's observations were confirmed by a team of UK and US scientists at Kech Observatory, Hawaii. PH1 is a gas giant with a radius about 6.2 times that of Earth, making it a bit bigger than Neptune. It orbits a pair of eclipsing stars that are 1.5 and 0.41 times the mass of the Sun, roughly every 138 days. The planet's temperature is thought to be far too hot to harbour life: scientists estimate it ranges from a minimum of about 251 degrees Celsius to a maximum of 340 degrees.

Dr. Chris Lintott of Oxford University said: "It's fascinating to try and imagine what it would be like to visit a planet with four suns in its sky, but this new world is confusing astronomers."

It is not at all clear how the planet managed to form, and remain in stable orbit, whilst being pulled at by the gravity of its many stars.

"All four stars pulling on it creates a very complicated environment", Dr. Lintott said. "Yet there it sits in an apparently stable orbit."

Yale astronomer Meg Schwamb explained that even the circumbinary planets are extremes of planet formation: "The discovery of these systems is forcing us to go back to the drawing board to understand how such planets can assemble and evolve in these dynamically challenging environments."

"Anyone viewing the sky from PH1 would have a spectacular view of all four stars", according to a blog post on the Planet Hunters website. "More importantly, this amazing system will help us understand how and where planets can form - producing a stable planet in a system where four different stars are moving about can't be easy."

The research paper about PH1's discovery was submitted to the Astrophysical Journal Monday at the annual meeting of the Division of Planetary Sciences of the American Astronomical Society in Reno, Nevada.

"I celebrate this discovery for the wow-factor of a planet in a four-star system", said Natalie Batalha, a Kepler scientist at the NASA Ames Research Center at Moffett Field, California in a release. "Most importantly, I celebrate this discovery as the fruit of exemplary human cooperation - cooperation between scientists and citizens who give of themselves for the love of stars, knowledge, and exploration."