April 27, 2017
Newly-discovered ice planet is ‘much colder than Hoth’
Researchers have discovered a new planet that has about the same mass as Earth and orbits its star at about the same distance separating our home planet from its sun – but that doesn’t mean that the conditions are suitable for life, as the planet is far too cold to be habitable.
In fact, as the study authors explained in this week in the Astrophysical Journal Letters, when covered in ice, the planet reaches temperatures of minus-400 degrees Fahrenheit, which makes it even colder than the mythical world of Hoth from the Star Wars universe, according to CNN.Fans of the popular sci-fi movie franchise will recall that Hoth was a frozen wasteland, and as the lead author said Yossi Shvartzvald, a postdoctoral from NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, explained, that’s a pretty apt description for the newly discovered planet, which has been named OGLE-2016-BLG-1195Lb.
OGLE-2016-BLG-1195Lb, Shvartzvald told CNN, is “actually much, much colder than Hoth. It’s hard to imagine any life surviving in such an environment, not humans or tauntauns anyway. ... The ice is not just scattered on the surface; it goes hundreds of miles deep,” and the world is even colder than Pluto, which itself is colder than liquid nitrogen, added co-author Jennifer Yee from the Harvard-Smithsonian Center for Astrophysics (CfA).
While the cold surface conditions and the lack of illumination and heat from the dim host star eliminate the possibility of the new planet being home to life as we know it, the researchers said in a press release that it will improve their understanding of planetary systems beyond our own.
Strange world discovered thanks to gravitational microlensing
According to Shvartzvald, Yee and their colleagues, OGLE-2016-BLG-1195Lb is the lowest mass world ever discovered through microlensing, a technique in which light from a star that passes in front of a bright background object causes the latter to appear brighter, thus allowing scientists to detect anomalies created by a planet orbiting in the foreground.
In the case of OGLE-2016-BLG-1195Lb, the spike in brightness lasted only a few hours, but Shvartzvald and Yee were able to detect it using the Optical Gravitational Lensing Experiment (OGLE) survey at the University of Warsaw and track it using both the Spitzer Space Telescope and the Korea Microlensing Telescope Network (KMTNet).
Despite the similarities between Earth and the newly-discovered planet in terms of mass and distance from their host star, the two worlds are very different in many other ways, the authors explained. OGLE-2016-BLG-1195Lb is approximately 13,000 light-years away and orbits an object so small that the researchers are not fully convinced that it’s even a star.
There is a shot the object is a brown dwarf (a star-like object which is incapable of generating energy through nuclear fusion at its core) or an ultra-cool dwarf similar to TRAPPIST-1. The star’s mass is less than 8 percent that of our sun, placing it right on the edge of qualifying for star status. Currently, they have no way of confirming for certain whether it is a star or not.
Nonetheless, Shvartzvald told CNN that the discovery “provides more evidence that planets are not only very common but also very diverse. They are able to form in strange environments very different from what we're accustomed to on Earth.”
Image credit: NASA