World Bulletin / News Desk
A joint effort of citizen scientists and professional astronomers has led to the first reported case of a planet orbiting twin suns that in turn is orbited by a second distant pair of stars.
Aided by volunteers using the Planethunters.org website, a Yale-led international team of astronomers identified and confirmed discovery of the phenomenon, called a circumbinary planet in a four-star system.
Only six planets are known to orbit two stars, according to researchers, and none of these are orbited by distant stellar companions.
“Circumbinary planets are the extremes of planet formation,” said Meg Schwamb of Yale, lead author of a paper about the system presented Oct. 15 at the annual meeting of the Division for Planetary Sciences of the American Astronomical Society in Reno, 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.”
Dubbed PH1, the planet was first identified by citizen scientists participating in Planet Hunters, a Yale-led program that enlists members of the public to review astronomical data from NASA’s Kepler spacecraft for signs of planets. It is the project’s first confirmed planet discovery.
The volunteers — Kian Jek of San Francisco and Robert Gagliano of Cottonwood, Arizona — spotted faint dips in light caused by the planet as it passed in front of its parent stars, a common method of finding extrasolar planets. Schwamb, a Yale postdoctoral researcher, led the team of professional astronomers that confirmed the discovery and characterized the planet, following observations from the Keck telescopes on Mauna Kea, Hawaii. PH1 is a gas giant with a radius about 6.2 times that of Earth, making it a bit bigger than Neptune.
"Planet Hunters is a symbiotic project, pairing the discovery power of the people with follow-up by a team of astronomers,” said Debra Fischer, a professor of astronomy at Yale and planet expert who helped launch Planet Hunters in 2010. “This unique system might have been entirely missed if not for the sharp eyes of the public."
An artist's illustration of PH1, a planet discovered by volunteers from the Planet Hunters citizen science project. PH1, shown in the foreground, is a circumbinary planet and orbits two suns. (Image by Haven Giguere/Yale)
PH1 orbits outside the 20-day orbit of a pair of eclipsing stars that are 1.5 and 0.41 times the mass of the Sun. It revolves around its host stars roughly every 138 days. Beyond the planet’s orbit at about 1000 AU (roughly 1000 times the distance between Earth and the Sun) is a second pair of stars orbiting the planetary system.
“The thousands of people who are involved with Planet Hunters are performing a valuable service,” said coauthor Jerome Orosz, who earned his Ph.D. at Yale in 1996 and is now associate professor of astronomy at San Diego State University. “Many of the automated techniques used to find interesting features in the Kepler data don't always work as efficiently as we would like. The hard work of the Planet Hunters helps ensure that important discoveries are not falling through the cracks."
The research was supported by NASA and the National Science Foundation Astronomy and Astrophysics Postdoctoral Fellowship.
Cassini skimmed closer than any previous spacecraft to the sixth planet from the Sun, and lived to tell the tale, sending back a signal that arrived early Thursday at 0656 GMT, about 20 hours after the crossing took place.
For first time ever, researchers grow working brain circuitry in a lab setting from stem cells
Current virtual assistants have been described as a step into an era of controlling computers by speaking instead of typing or tapping screens.
Saturn has more than 60 moons, and Cassini has made new discoveries on some of them, which may have conditions suitable for a form of life.
Facebook is looking at creating "silent-speech interfaces" based on sensors that could be worn, and made in quantity.
The arbitration court in Moscow approved the deal which lasts for six years and nine months, Russian news agencies said.
The security improvement was described as being part of a broader effort to rid the leading social network of hoaxes, misinformation and fake news by verifying people's identities.
Last year, Musk announced that Tesla plans to build a new pickup truck, an urban bus, and launch a sharing system of self-driving cars.
Plunging the Cassini spacecraft down over Saturn's moon Enceladus , the space agency was able to capture samples of water plumes erupting from the surface.
Enceladus likely contains environments similar to Earth
Facebook chief Mark Zuckerberg has sought to deflect criticism that the huge social network may have been used to fuel the spread of misinformation that affected the 2016 US presidential race.
The inexpensive technique, which can have broad applications in monitoring and protecting aquatic life, was conducted in the East River, which is actually an inlet, and the Hudson River last year.
The skin sensors currently used to monitor vital signs in babies born prematurely generate false alarms in up to 90 percent of cases, mainly set off by the baby's movement.
Social media platform says government summons for user’s identity was withdrawn
Social media company reveals lengthy list of tips to improve its users’ ability to spot hoaxes
The proceedings, against Apple Pty Limited and its US-based parent Apple Inc, were brought on behalf of 275 consumers.