Earthlike exoplanet in habitable zone detected orbiting nearest star
The uncertainty of science: Astronomers think they have detected an Earthlike exoplanet, in habitable zone, orbiting Proxima Centauri, the nearest star to our solar system.
Astronomer João Faria and his collaborators detected Proxima Centauri d by measuring tiny shifts in the spectrum of the star’s light as the planet’s gravity pulled it during orbit. The team used a state-of-the art spectrograph called ESPRESSO at the Very Large Telescope, a system of four 8.2-metre telescopes at the European Southern Observatory in Cerro Paranal, Chile. The results were published on 10 February in Astronomy & Astrophysics.
This ‘wobble’ technique looks for changes in the star’s motion along the line of sight from Earth, and ESPRESSO can detect variations of just 10 centimeters per second. The total effect of the planet’s orbit, which lasts only five days, is about 40 cm/s, says Faria. “I knew that ESPRESSO could do this, but it was still surprised to see it showing up,” says Faria, who is at the Institute of Astrophysics and Space Sciences in Porto, Portugal.
Though the scientists are very confident about their results, the detection is at present only a candidate planet, as its existence has not been confirmed by an second independent method. Also, the method of detection cannot pin down the exoplanet’s mass very precisely, though it suggests the exoplanet has rocky planet mass, not too different than Earth’s.
The uncertainty of science: Astronomers think they have detected an Earthlike exoplanet, in habitable zone, orbiting Proxima Centauri, the nearest star to our solar system.
Astronomer João Faria and his collaborators detected Proxima Centauri d by measuring tiny shifts in the spectrum of the star’s light as the planet’s gravity pulled it during orbit. The team used a state-of-the art spectrograph called ESPRESSO at the Very Large Telescope, a system of four 8.2-metre telescopes at the European Southern Observatory in Cerro Paranal, Chile. The results were published on 10 February in Astronomy & Astrophysics.
This ‘wobble’ technique looks for changes in the star’s motion along the line of sight from Earth, and ESPRESSO can detect variations of just 10 centimeters per second. The total effect of the planet’s orbit, which lasts only five days, is about 40 cm/s, says Faria. “I knew that ESPRESSO could do this, but it was still surprised to see it showing up,” says Faria, who is at the Institute of Astrophysics and Space Sciences in Porto, Portugal.
Though the scientists are very confident about their results, the detection is at present only a candidate planet, as its existence has not been confirmed by an second independent method. Also, the method of detection cannot pin down the exoplanet’s mass very precisely, though it suggests the exoplanet has rocky planet mass, not too different than Earth’s.
