Table of Contents
HSpot is a complex and evolving system to which constant improvements have been made through a series of planned new releases at key dates in the Herschel schedule. Many of these changes have been 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 have had 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 HSpot since the release of the final Phase 2 version for the OT2 Call for Proposals was made (HSpot v5.3.2).
HSpot users who have prepared previously observations with HSpot were well aware that there were numerous changes that affected already prepared Astronomical Observation Requests (AORs) between the 5.2 and 5.3 versions of HSpot. However, between the 5.3.2 version and 6.0.0, although many updates were made, few of these directly affected observers in obvious ways. Observing modes have been extremely stable during most of the mission, with changes now limited to fine tuning that affects very few observations. Time estimates that were previously prepared with earlier HSpot versions will show in red as out of date and must always be re-calculated, although any differences are invariably small and limited to a handful of AORs. 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 stable with good knowledge of the instruments available, there is a constant tweaking of the way that observations are taken to optimise data quality where changes are found that would be beneficial. This process is continuing right through to helium exhaustion.
Users are strongly recommended to read this document in conjunction with the relevant Observers' Manuals and the HSpot Users' Guide.
HSpot 6.x is our routine operations version of HSpot for scheduling observations from the OT2 Call for Proposals and through to end of helium, although there may possibly be a final, incremental update of HSpot for post-Operations. A further slough of changes have been made to HSpot relative to the final OT1 Call version (5.3.2). There has been a careful optimisation of the newer, second-generation observing modes. At the same time, some updates have been made in the Spot Core that have been incorporated in these releases. Between versions 5.2 and 6.0 there were numerous 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. This has continued through HSpot 6.3.0. 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, but which are essential to the success of observations.
Between the 5.3.1 version of HSpot and 5.2.3 no less than 27 problems were fixed, or updates applied. 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 were relatively complex to implement and required interation over intermediate versions to ensure that they are correct. HSpot 6.0.0 incorporated 14 further updates, with smaller numbers in later versions as observing modes became stable, robust and thoroughly flight-tested.
Increasingly though, as HSpot is used on operating systems far more modern than the ones for which it was designed and with multiple platforms that were not even contemplated at Herschel's launch, platorm-dependent problems are appearing (e.g. we cannot hope to support and Acceptance Test HSpot with every flavour of Linux, so have to take the most common ones as indicative of the behaviour of HSpot with the rest). Most of these are minor and have affected few users, others have been more widespread and extremely challenging to resolve.
No attempt is made to describe every single HSpot change. Here we describe only the changes that will have a significant effect on the way HSpot works or that will be obvious to the user.
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, "HCSS" that it was raised on the Herschel Common Software System-), the title of the Bug Report or Software Change Request and brief details of its resolution and effects on HSpot.