Planet With Four Suns Discovered

An international team of astronomers have
announced the discovery of a planet whose
skies are illuminated by four suns – the first
known of its type.
The planet, located about 5,000 light years from
Earth, has been dubbed PH1 in honor of Planet
Hunters, a programme led by Yale University in
the United States which enlists volunteers to look
for signs of new planets.
PH1 is orbiting two suns, and in turn is orbited by
a second distant pair of stars. Only six planets
are known to orbit two stars, researchers say,
and none of those are orbited by other distant
stars.
“Circumbinary planets are the extremes of planet
formation,” said Yale’s Meg Schwamb, lead
author of a paper presented Monday at the
annual meeting of the Division for Planetary
Sciences of the American Astronomical Society in
Nevada.
“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.”
US citizen scientists and Planet Hunters
participants Kian Jek and Robert Gagliano were
the first to identify PH1. Their observations were
then confirmed by a team of US and British
researchers working in 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 two other stars are orbiting the planetary
system at a distance that is roughly 1,000 times
the distance between Earth and the Sun.
The Planethunters.org website was created in
2010 to encourage amateur astronomers to
identify planets outside our solar system, using
data from the US space agency NASA’s Kepler
space telescope.
Kepler, launched in March 2009, is NASA’s first
mission in search of Earth-like planets orbiting
stars similar to our Sun.
The discovery of PH1 was made available online
Monday at the site arxiv.org and has been
submitted to the Astrophysical Journal for
publication.
“It still continues to astonish me how we can
detect, let alone glean so much information,
about another planet thousands of light-years
away just by studying the light from its parent
star,” Jek said.
Source: Aljazeera