Benefits of the p2 web application

Full integration into the web browser


p2 allows users to create the ESO Phase 2 material via an intuitive web User Interface (UI). As such, the use of p2

  • does not require the installation of a dedicated software
  • users do not need to do any software update/upgrade
  • allows a flexible software maintenance
  • allows a platform independent creation of Phase 2 material
  • has no dependency on a local cache for data-storage
  • PIs and Phase 2 delegates directly share the content of the Phase 2 material of a specific run by simply logging into the p2 interface using their respective ESO User Portal credentials
  • multiple log-in and shared work is now possible

p2 is implemented using Google’s angular framework []. Please check here for a complete list of supported browsers. 

Observing Blocks are created against the ESO database via a dedicated API


Using p2, users now create and modify their Phase 2 observing material directly against the ESO database. This is made possible by the fact that p2 is a User Interface that allows a user-friendly use of a dedicated Application Programming Interfaces (API). In this context, obvious benefits are:

  • no check-in/check-out of OBs is required anymore
  • the action of submitting the Phase 2 material is now replaced by a simple notification action; once the Phase 2 material is ready (even partially) the user will inform ESO using the dedicated "Notify ESO" button, that the observing material is ready to be reviewed by the User Support Department (for Service Mode) or Paranal (for Visitor Mode)
  • no back-up is required. The user will be able to export OBs from the p2 UI
  • the ingestion and production of large number of OBs is now possible by coding against the API. Please see the dedicated section below   

The  Phase 2 Application Programming Interface (API)

Users can programmatically create and edit large amount of OBs using the dedicated Phase 2  Application Programming Interface (API). In short, the API uses the lightweight JavaScript Object Notation (JSON) standard as data format to exchange information between the user-dedicated application and the Phase 2 server at ESO.

We strongly encourage ESO users who are planning to systematically produce large amount of OBs (e.g. Large Program, Surveys runs) to familiarize with the ESO API at the following pages:

and (recommended for testing purposes)

In order to program more conveniently against the API, it is helpful to create small, language-specific bindings to the API. Detailed instructions and practical examples using Python are provided at the pages above. Here for further details.