Last November, Aussie astronomers reported the discovery of an amazing "diamond" planet that was five times the size of the Earth and composed primarily of diamond. The super-dense planet, which started off as a massive white dwarf star, is located 4,000 light years away in the Serpens constellation. Now another diamond planet is in the news, and this one's only 40 light years away in the constellation of Cancer. The planet named "55 Cancri e" is about twice the size of the Earth, but has eight times its density. Astrophysicists from Yale University believe a third of the planet is made of graphite and diamond. The amount of diamond in the planet could be equivalent to three times the mass of the Earth. “On this planet there would basically be a thin layer below the surface which will have both graphite and diamond,” Yale researcher Nikku Madhusudhan told Universe Today. “But, below that there will be a thick layer (a third of the radius) with mostly diamond. For a large part, the diamond will be like the diamond on Earth, except really, really pure. But at greater depths the diamond could also be in liquid form.” A Forbes magazine columnist took a crack at estimating the value of 55 Cancri e and came up with the staggering number of $26.9 nonillion. (This is $26.9 followed by 30 zeros.) Wow. Sadly, the prospects of mining the gem riches of the distant planet are slim to none. You see, the surface temperature is 3,900 degrees Fahrenheit, and the big bauble is some 230 trillion miles away. Visit Ben David Jewelers on Facebook Visit BenDavidJewelers.com Find us on Pinterest.