<http://schema.org/alternativeHeadline>
"The exoplanet 55 Cancri e is 60 percent larger in diameter than Earth but eight times as massive, making the alien world the densest solid planet known \u2013 twice as dense as Earth."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/space/stories/alien-planet-nearly-dense-as-lead>