No, 55 Cancri e isn't an exoplanet anyone will want to visit anytime soon. Because it orbits so close to its star, the world has a surface temperature of around 2,000 degrees Celsius. But that hasn't prevented the planet, recently named "Janssen" by the International Astronomical Union, from having an atmosphere. And it's an interesting atmosphere indeed.

Discovered back in 2004, Janssen was one of the first "super Earths" found by astronomers. These planets, larger than Earth but considerably smaller than the gas giants of the Solar System, are thought to be the most common type of planets in the galaxy. Now, using a technique to tease atmospheric data out of Hubble Space Telescope observations, scientists have been able to deduce the atmosphere of this particular super Earth.

According to results published in the Astrophysical Journal, European astronomers have found hydrogen and helium in the atmosphere around Janssen, which may have a diamond-like core due to its very high density. This atmosphere is likely a remnant of the nebula from which the planet and its star formed about 8 billion years ago. The planet has kept this atmosphere somehow, despite the proximity of its star.

The researchers also found a signal for hydrogen cyanide, a poisonous gas. While this discovery certainly adds to the undesirability of Janssen as a tourist destination, hydrogen cyanide does increase the likelihood of Janssen being a diamond-like planet. “If the presence of hydrogen cyanide and other molecules is confirmed in a few years time by the next generation of infrared telescopes, it would support the theory that this planet is indeed carbon rich and a very exotic place," said astronomer Jonathan Tennyson of University College London.

Astronomers have used this technique to look at two other super Earths but did not find atmospheres around them. The method works best with planets very close to their stars. This is because the scientists obtain the spectra by scanning the Hubble's Wide Field Camera 3 multiple times across the star and then use software to disentangle the information about the planet's atmosphere from the starlight.