Sir Isaac Newton predicted the world would end in the year 2060, scribbling the date on a piece of paper, according to theories uncovered by academics in Jerusalem.
The prophecy has been unearthed from little-known handwritten manuscripts in a library, a BBC documentary due to screen on Saturday will show.
The pages show Newton's attempts to decode the Bible, which he believed contained God's secret laws for the universe.
The most definitive date he set for the apocalypse, which he scribbled on a scrap of paper, was 2060.
In the case of GJ 436b, the hot Neptune, there are two possible explanations for the lack of observed features in the spectrum: either the planet has an atmosphere that's nearly devoid of hydrogen, or it's covered in a layer of high clouds. Right now, the error bars of their measurements encompass models of both of these options, but they say that some additional observation time will allow them to rule one or the other out.
In the case of Super-Earth GJ 1214b, however, the authors already have enough observations to rule out the hydrogen-poor atmosphere. That leaves clouds as the only viable explanation for the spectrum that they see.
These clouds are almost certainly not the water vapor clouds that we see on Earth. Both exoplanets are much closer to their host stars, with correspondingly hotter atmospheres. As a result, both papers suggest that the clouds are likely to be composed of what we would call salts in their solid form: "Zinc sulphide and potassium chloride are both plausible candidates for the composition of the cloud." On the Super-Earth, the authors also indicate that a Titan-like atmosphere, where UV light has triggered chemical reactions that create complex hydrocarbons, is also a possibility.