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NASA Spies Earth-Sized Exoplanet Orbiting Sun-Like Star
An anonymous reader writes: NASA has announced that a new Earth-like planet has been discovered that may be the closest thing yet to a first true "Earth twin." Kepler 452b is located 1,000 light years away, is 60% larger than Earth, and orbits Kepler 452 at a distance similar to that between Earth and the Sun. "It is the first terrestrial planet in the habitable zone around a star very similar to the Sun," says Douglas Caldwell, an astronomer at the SETI Institute in Mountain View, California.
Except, of course, at 1000 light years away ... there are no EM radiations from us which would have reached there.
Sorry to burst your bubble.
Lost at C:>. Found at C.
"Note this world is rather denser than Earth - 5x the mass packed into 4x the volume. Should be a great place for heavy metal poisoning. Or toxic wastelands. Something like that...."
Not necessarily. A planet with a larger radius retains heat better thanks to its lower surface area to volume ratio, and a planet with higher gravity will more efficiently separate its component materials by density, i.e. drawing metal elements into its core. And since the planet is retaining more heat, it will probably have had more resurfacing and tectonic activity than Earth did. So a denser planet does have more metals, but by being larger it is also going to have a lower proportion of it [metals present during formation] in its crust than a 1G planet.
As to which effect dominates in this situation, that's a question for someone with an actual model of planetary evolution.