Publication date: 30/06/2014

On 27 June 2014, ATHENA was selected as the second L-class mission in ESA’s Cosmic Vision 2015–2 5 plan, with a launch foreseen in 2028.

The mission has now entered the study phase; once the mission design and costing have been completed, it will eventually be proposed for ‘adoption’ around 2019, before the start of the construction phase. By combining a large X-ray telescope with state-of-the-art scientific instruments, Athena will address key questions in astrophysics

ATHENA will predominantly perform pointed observations of celestial targets. There will be around 300 such observations per year, with durations ranging from 103 to 106 seconds, with a typical duration 105 seconds per pointing. This routine observing plan will be interrupted by target of opportunity observations (for example, gamma ray bursts and other transient events) at an expected rate of twice per month.

The baseline mission duration for ATHENA will be five years, with consumables sized to allow a five-year extension to maximise the return from this ambitious mission. With a conservative observing efficiency of 75%, ATHENA will be able to achieve the science goals of the Hot and Energetic Universe theme during the baseline mission, while preserving a large fraction (30–40%) of the available time for observatory science.