Alpha Centari B, the secondary star of the closest star system to earth besides our own, apparently has a new companion. First noticed on October 18th, scientists have recently revealed that a rocky planet 1.13 times the mass of earth orbits this neighbor of ours. However, this planet has orbital period of 3.236 days, meaning that it's extremely close to its parent star, and thus way to hot to be habitable.
Xavier Dumusque of the Geneva Observatory in Switzerland and his colleagues discovered this planet using the HARPs spectrograph to break apart light from Alpha Centari B. After filtering out starspots and other noise, they found a tiny fluctuation that they claim is caused by an earth-mass planet. Other observatories will check soon in an attempt to either confirm this planet's existence or disprove it.
As planet-finding techniques become more precise, scientists continue to discover unexpected worlds - but just one 4 light-years away is especially exciting. Now it's only time before this planet's presence is confirmed.
Source: Astronomy Magazine, Vol 41, No. 2