Chapter 1. Introduction

Table of Contents

1.1. A note on changes made between HSpot v5.0 and v5.2

HSpot is a complex and evolving system to which improvements are being made through a series of planned new releases at key dates in the Herschel schedule. Many of these changes are essentially invisible to the vast majority of users (additional specialist functionality used only by the HSC or the expert users at the ICCs, cosmetic improvements, changes to the Spot core, improved characterisation of instruments, bug fixes, proposal handling changes, etc.), some though may have a significant impact on all users, particularly those related to time estimation.

The purpose of this document is to give a guide to the main changes that have been made in the Astronomical Observing Templates (AOTs) for each instrument since the release of the final user version for the 2010 Call for Proposals was made (HSpot v5.0). HSpot users who have prepared previously observations with HSpot should be aware that there are numerous changes that will affect already prepared Astronomical Observation Requests (AORs); these are detailed in this document. Time estimates that were previously prepared with HSpot v5.0 may be out of date and must always be re-calculated, although the differences are usually small. Even when time estimates do not change, there are important underlying differences in the software that make a real difference to how the observations are executed on board, so even apparently neutral time estimator changes may be very important for your data. Since launch there have been regular changes in the software that controls the AOTs, with frequent changes of software version (Mission Configuration); each Mission Configuration links to a new time estimator version; while time estimation is now more stable as better knowledge of the instruments is available, there is a constant tweaking of the way that observations are taken to optimise data quality.

Users are strongly recommended to read this document in conjunction with the relevant Observers' Manuals and the HSpot Users' Guide.

1.1. A note on changes made between HSpot v5.0 and v5.2

HSpot 5.2 is our routine operations version of HSpot for Phase 2 the OT1 Call for Proposals. A further slough of changes have been made to HSpot relative to the final Science Demonstration Phase version (4.4.4) to take into account the frequently major changes in the way that observations are carried out in flight compared to the pre-launch version. Science Demonstration Phase and early Routine Operations showed that some observing modes needed to be radically re-designed to optimise them and also showed the need for new, second-generation observing modes in some cases. At the same time, updates have been made in the Spot Core that have been incorporated in these releases. There have been several intermediate releases that astronomers did not see; often these patch specific functionality needed by the instruments in their Expert User mode that may have no impact on the astronomer save to give him a better understood and calibrated instrument and to allow the HSC to test changes in the code thoroughly before the are released to users. Many of the changes in these intermediate versions affect only the software specific to the HSC and ICCs such as the Mission Planning System, or the proposal processing, which the proposer will never see.

The 5.2 version of HSpot involves many changes. No less than 25 problems are fixed, or updates applied by HSpot 5.2.1 relative HSpot 4.4.4. Most were fairly small changes were required to bring HSpot in-line with in-flight reality, as the modification, or deprecation, or inclusion of observing modes requires other, related changes in HSpot. Some of the changes have been relatively complex to implement and have required interation over intermediate versions to ensure that they are correct.

No attempt is made to describe every single HSpot change. Here we describe only the major changes that will have a significant effect on the way HSpot works or that will be obvious to the user.

Since the 4.4.4 release, the pre-launch method of functioning has become inadequate. Members of the HSC Instrument and Calibration Scientist Team are deeply involved in testing and quality control and have less time available for pure documentation, hence listings are given of the relevant bugs patched (System Problem Reports, or SPRs) and changes made (System Change Requests, or SCRs) tracked by the HSC rather than an analysis of changes. The ones reproduced and commented in this document are just a small part of the fixes and updates that are routinely made on the system.

For each change, the problem or change request number is given (prefixed by "PHS-SxR" to say that it was raised on the Proposal Handling System), the title of the Bug Report or Software Change Request and brief details of its resolution and effects on HSpot.