A year is only 17.5 hours long on the ‘hell planet’

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Exoplanet 55 Cancri e has several names, however the rocky world located 40 light years from Earth is the best known because of its reputation as a “hell planet”.

This super-Earth, so named because it is a rocky planet eight times more massive and twice as wide as Earth, is so scorching hot that it has a molten lava ocean for a surface which reaches 3,600 degrees Fahrenheit (1,982 degrees Celsius).

The interior of the exoplanet could also be full of diamonds.

The planet is hot enough as it has been compared to Star Wars lava world mustafarsite of the battle between Anakin Skywalker and Obi-Wan Kenobi in “Revenge of the Sith”, and where Darth Vader later establishes his castle, Fortress Vader.

The planet, formally named Janssen but also known as 55 Cancri and 55 Cnc e, orbits its host star Copernicus so closely that the sparkling world completes one orbit in less than one Earth day. A year for this planet lasts about 17.5 hours on Earth.

The incredibly tight orbit is why Janssen has such intense temperatures, so close that astronomers doubted a planet could exist while practically hugging a host star.

Astronomers wondered if the planet had always been this close to its star.

A team of researchers used a new tool known as EXPRES, or EXtreme PREcision Spectrometer, to determine the precise nature of the planet’s orbit. The findings may help astronomers gain new insight into how planets form and how these celestial bodies evolve an orbit

The instrument 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 small changes in the light of the Copernican stars as Janssen moved between our planet and the star, such as when the moon blocks the sun during a solar eclipse.

The researchers determined that Janssen orbits along the star’s equator. But the inferno planet is not the only planet that orbits Copernicus. Four other planets on different orbital paths populate the star system.

Astronomers believe that Janssen’s odd orbit suggests that the planet initially started out in a cooler, more distant orbit before approaching Copernicus. Then the gravitational pull of the star’s equator changed Janssen’s orbit.

The newspaper Astronomy of nature published a study detailing the findings on Thursday.

“Astronomers expect this planet to have formed much further away and then spiraled into its current orbit,” Fischer, the study’s lead author and the Eugene Higgins Professor of Astronomy at Yale, said in a statement. “That trip could have pushed the planet out of the star’s equatorial plane, but this result shows that the planet stayed strong.”

Although Janssen has not always been so close to its star, astronomers concluded that the exoplanet was always hot.

The planet “was probably so hot that nothing we know could survive on the surface,” study lead author Lily Zhao, a researcher at the Center for Computational Astrophysics at the Flatiron Institute in New York, said in a communicated

Once Janssen approached 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 of them do not host planets that orbit in a flat plane, raising the question of how unique our solar system is in the universe.

This kind of data could provide more insight into how Earth-like planets and environments can exist in the universe.

“We hope to find planetary systems similar to our own and better understand the systems we know,” Zhao said.

The main goal of the EXPRES instrument is to detect Earth-like planets.

“Our accuracy 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 measurement was the main goal of my career because it allows us to detect smaller planets while searching for Earth analogues.”