INSTANT (INvestigation of Solar-Terrestrial Activity aNd Transients) is a joint mission project between the European Space Agency (ESA) and the Chinese Academy of Sciences (CAS). In the scope of the CAS-ESA call for a small mission, INSTANT proposes an innovative space observatory at the Lagrangian L5 point dedicated to the observation of the Sun-Earth interaction. It will provide novel observations and address fundamental questions in solar, heliospheric and space weather sciences. The launch of this S-class mission is scheduled for 2021 and the nominal science operations will last 2.5 years.

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NEWS 20/04/15

Unfortunately, we recently learned that the INSTANT mission proposal was not selected for further assessment in this call.

The mission concept yet remains promising, and without doubt mission concepts derived from it will be proposed in the future in other programmatic opportunities.

NEWS 17/03/15

We’re happy to let you know that the INSTANT mission proposal is now submitted! Here is the Executive Summary.

Thank you so much to all who have helped and supported the mission preparation!

A complete update of the website is now ongoing to reflect the final design and objectives of INSTANT.

NEWS 20/01/15

The “Joint Call for a mission from ESA and the Chinese Academy of Sciences (CAS)” has been released. The requirements of the proposal and the mission can be found there:

Announcement Letter
Joint Call for Missions
Proposal template
Technical Annex CAS-ESA Call

NEWS 13/01/15

INSTANT website is online!