Higher than expected levels of sodium found in a 4.6 billion-year-old meteorite suggest that the dust clouds from which the building blocks of the Earth and neighboring planets formed were much denser than previously supposed.

Astronomers are looking to identify Earth-like watery worlds circling distant stars from a glint of light seen through an optical space telescope and a mathematical method developed by researchers at Penn State and the University of Hawaii.

In a find that sheds light on how Earth-like planets may form, astronomers this week reported finding the first evidence of small, sandy particles orbiting a newborn solar system at about the same distance as the Earth orbits the sun. The report will be published online this week by the journal Nature.

With powerful instruments scouring the heavens, astronomers have found more than 240 planets in the past two decades, none likely to support Earth-like life.

In April, a European team of astronomers announced in Astronomy & Astrophysics the discovery of two possibly habitable Earth-like planets. A&A is now publishing two independent, detailed studies of this system, which confirm that one of the planets might indeed be located within the habitable zone around the star Gliese 581.

In the Star Wars movies fictional planets are covered with forests, oceans, deserts, and volcanoes. But new models from a team of MIT, NASA, and Carnegie scientists begin to describe an even wider range of Earth-size planets that astronomers might actually be able to find in the near future.

Astronomers have discovered the most Earth-like planet outside our Solar System to date, an exoplanet with a radius only 50% larger than the Earth and capable of having liquid water. Using the ESO 3.6-m telescope, a team of Swiss, French and Portuguese scientists discovered a super-Earth about 5 times the mass of the Earth that orbits a red dwarf, already known to harbour a Neptune-mass planet.