A year lasts only 17.5 hours on the “hell planet”
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Exoplanet 55 Cancri e goes by several names, but the most famous is the rocky world located 40 light years from Earth because of its reputation as a “hell planet”.
This super-Earth, so named because it is a rocky planet eight times as massive and twice as wide as Earth, is so hot that it has an ocean of molten lava for a surface which reaches 3600 degrees Fahrenheit (1982 degrees Celsius).
The interior of the exoplanet may also be full of diamonds.
The planet is hot enough as it was compared to Star Wars lava world of Mustafarthe site of the battle between Anakin Skywalker and Obi-Wan Kenobi in Revenge of the Sith and where Darth Vader later established his castle, Vader’s Fortress.
The planet, officially named Janssen but also called 55 Cancri e or 55 Cnc e, orbits its host star Copernicus so closely that the smoldering world completes one orbit in less than one Earth day. A year for this planet lasts about 17.5 hours on Earth.
The incredibly narrow orbit is why Janssen has such high temperatures — so close that astronomers doubted a planet could exist while practically hugging a host star.
Astronomers wondered if the planet had always been so close to its star.
A team of researchers used a new instrument known as the EXPRES or EXtreme PREcision Spectrometer to determine the exact nature of the planet’s orbit. The findings could help astronomers gain new insight into how planets form and how these celestial bodies evolve orbit.
The tool was developed at Yale University by a team led by astronomer Debra Fischer and installed on the Lowell Discovery Telescope at the Lowell Observatory in Flagstaff, Arizona. The spectrometer was able to measure tiny changes in the Copernicus starlight as Janssen moved between our planet and the star — like when the moon blocks the sun during a solar eclipse.
The researchers found that Janssen orbited the star’s equator. But the infernal planet is not the only planet orbiting Copernicus. Four other planets on different orbital paths populate the star system.
Astronomers believe that Jansen’s odd orbit suggests that the planet originally started out in a cooler and more distant orbit before approaching Copernicus. Then the gravitational pull from the star’s equator changed Jansen’s orbit.
The diary Natural astronomy published a study detailing the findings on Thursday.
“Astronomers expect that this planet formed much further away and then spiraled into its current orbit,” Fischer, the study’s senior author and the Eugene Higgins Professor of Astronomy at Yale, said in a statement. “This trip could have thrown the planet out of the star’s equatorial plane, but this result shows that the planet is holding on tight.”
Despite the fact that Janssen was not always so close to its star, astronomers concluded that the exoplanet was always hot.
The planet “was probably so hot that nothing we know of could survive on the surface,” study lead author Lily Zhao, a research associate at the Flatiron Institute’s Center for Computational Astrophysics in New York, said in a statement.
Once Jansen moved closer to Copernicus, the infernal planet it got even hotter.
Our solar system is flat like a pancake, where all the planets orbit the sun in a flat plane because they all formed from the same disk of gas and dust that once orbited our sun.
As astronomers have studied other planetary systems, they have discovered that many do not host planets orbiting in a flat plane, raising the question of how unique our solar system is in the universe.
This kind of data could provide more information about how many common planets and Earth-like environments may exist in the universe.
“We hope to discover planetary systems similar to our own and better understand the systems we know about,” Zhao said.
The primary goal of the EXPRES instrument is to spot Earth-like planets.
“Our precision with EXPRES today is more than 1,000 times better than what we had 25 years ago when I started working as a planet hunter,” Fischer said. “Improving the precision of the measurements has been a major goal of my career because it allows us to detect smaller planets while searching for Earth counterparts.”