Gaia’s first year of scientific observations

On 21 August 2015, ESA’s billion-star surveyor, Gaia, completed its first year of science observations in its main survey mode.

Gaia’s first Hertzsprung-Russell diagram

Proxima Centauri observed in X-rays by Chandra space telescope

Chandra and XMM-Newton observations of the red dwarf star Proxima Centauri have shown that its surface is in a state of turmoil. Flares, or explosive outbursts, occur almost continually. In the cores of low mass stars, nuclear fusion reactions that convert hydrogen to helium proceed very slowly, and create a turbulent, convective motion throughout their interiors. This motion stores up magnetic energy which is often released explosively in the star’s upper atmosphere where it produces flares in X-rays and other forms of light.

Rare Stellar Alignment Offers Opportunity to Hunt for Planets

The nearest star to our Sun, the red dwarf Proxima Centauri, is on a course for a rare conjunction with two distant background stars. This alignment will offer astronomers a unique opportunity to look for planets orbiting close to Proxima Centauri. In addition, astronomers will be able to precisely measure the mass of this isolated red dwarf. 

NASA, ESA, K. Sahu and J. Anderson (STScI), H. Bond (STScI and Pennsylvania State University), M. Dominik (University of St. Andrews), and Digitized Sky Survey (STScI/AURA/UKSTU/AAO)

Gaia's antenna in the test chamber

Entombed by the distinctive foam pyramids typical of test chambers, the main antenna of the Gaia billion-star surveyor has been put through its paces ahead of launch next year.

The 1.5m wide Gaia Antenna Panel, which contains the satellite’s Phased Array Antenna, is seen here inside the Antenna Test Facility at EADS CASA test facility in Madrid. Credit: Astrium–A. Martin, 2012